Merge main into feat/runpod-serverless-workers

Resolve nodes/collector.py: keep the serverless manager accessor and
main's compressed result transfer. Update test stubs for the merged
code: fetch_worker_has_node (#99) in the serverless integration test,
and the real aiohttp.web in the transfer integration test.

README.md

@@ -38,11 +38,12 @@
 
 <img width="200" align="right" alt="ComfyUI_temp_khvcc_00034_@0 25x" src="https://github.com/user-attachments/assets/651e4912-7c23-4e32-bd88-250f5175e129" />
 
-ComfyUI Distributed supports three types of workers:
+ComfyUI Distributed supports four types of workers:
 
 - **Local Workers** - Additional GPUs on the same machine (auto-configured on first launch)
 - **Remote Workers** - GPUs on other computers in your network
 - **Cloud Workers** - GPUs hosted on a cloud service like Runpod, accessible via secure tunnels
+- **Serverless (Runpod)** - Queue-based Runpod endpoints for image Collector jobs; no Distributed install or inbound tunnel on workers. [Setup, endpoint contract, and preview limitations](/docs/serverless-workers.md).
 
 > For detailed setup instructions, see the [setup guide](/docs/worker-setup-guides.md)
 
@@ -220,6 +221,26 @@ Yes, it is compatible with Docker setups, but you will need to configure your Do
 
 ---
 
+## Community projects
+
+Community-maintained add-ons and forks that extend ComfyUI-Distributed.
+
+### [ComfyUI-H3MC-Distributed](https://github.com/ymiyad/ComfyUI-H3MC-Distributed) by ymiyad
+
+Connects H3 Motion Context with ComfyUI-Distributed to generate multiple candidate takes of the next video clip across your workers. Compare the results, pick your preferred take, and use it as context for the next clip.
+
+Each saved candidate video includes its continuation latent, so you don't need a shared folder or separate latent files. This add-on speeds up iteration through parallel candidates; it does not split a single clip across GPUs.
+
+### [ComfyUI-Deadline-Distributed](https://github.com/doubletwisted/ComfyUI-Deadline-Distributed) by doubletwisted
+
+A fork of ComfyUI-Distributed with Thinkbox/AWS Deadline 10 integration for render farms. Claim Deadline workers from the Distributed panel, register them automatically, and collect their results back into your master workflow.
+
+Requires Deadline 10 and the author's ComfyUI-Deadline-Plugin.
+
+See each repository for installation instructions, requirements, and support.
+
+---
+
 ## Disclaimer
 
 This software is provided "as is" without any warranties, express or implied, including merchantability, fitness for a particular purpose, or non-infringement. The developers and copyright holders are not liable for any claims, damages, or liabilities arising from the use, modification, or distribution of the software. Users are solely responsible for ensuring compliance with applicable laws and regulations and for securing their networks against unauthorized access, hacking, data breaches, or loss. The developers assume no liability for any damages or incidents resulting from misuse, improper configuration, or external threats.

__init__.py

@@ -1,29 +1,22 @@
-# Import everything needed from the main module
-from .distributed import (
-    NODE_CLASS_MAPPINGS as DISTRIBUTED_CLASS_MAPPINGS, 
-    NODE_DISPLAY_NAME_MAPPINGS as DISTRIBUTED_DISPLAY_NAME_MAPPINGS
-)
+"""ComfyUI-Distributed's native V3 extension entrypoint."""
+from comfy_api.v0_0_2 import ComfyExtension, io
 
-# Import utilities
-from .utils.config import ensure_config_exists, CONFIG_FILE
-from .utils.logging import debug_log
+from .nodes.v3 import NODES
+from .runtime.bootstrap import initialize
 
-# Import distributed upscale nodes
-from .nodes.distributed_upscale import (
-    NODE_CLASS_MAPPINGS as UPSCALE_CLASS_MAPPINGS,
-    NODE_DISPLAY_NAME_MAPPINGS as UPSCALE_DISPLAY_NAME_MAPPINGS
-)
+WEB_DIRECTORY = './web'
 
-WEB_DIRECTORY = "./web"
 
-ensure_config_exists()
+class DistributedExtension(ComfyExtension):
+    async def on_load(self) -> None:
+        initialize()
 
-# Merge node mappings
-NODE_CLASS_MAPPINGS = {**DISTRIBUTED_CLASS_MAPPINGS, **UPSCALE_CLASS_MAPPINGS}
-NODE_DISPLAY_NAME_MAPPINGS = {**DISTRIBUTED_DISPLAY_NAME_MAPPINGS, **UPSCALE_DISPLAY_NAME_MAPPINGS}
+    async def get_node_list(self) -> list[type[io.ComfyNode]]:
+        return list(NODES)
 
-__all__ = ['NODE_CLASS_MAPPINGS', 'NODE_DISPLAY_NAME_MAPPINGS']
 
-debug_log("Loaded Distributed nodes.")
-debug_log(f"Config file: {CONFIG_FILE}")
-debug_log(f"Available nodes: {list(NODE_CLASS_MAPPINGS.keys())}")
+async def comfy_entrypoint() -> DistributedExtension:
+    return DistributedExtension()
+
+
+__all__ = ['comfy_entrypoint', 'WEB_DIRECTORY']

api/__init__.py

@@ -1,4 +1,5 @@
 from . import config_routes  # noqa: F401
+from . import serverless_routes  # noqa: F401
 from . import tunnel_routes  # noqa: F401
 from . import worker_routes  # noqa: F401
 from . import job_routes  # noqa: F401

api/config_routes.py

@@ -1,5 +1,6 @@
 import json
 from contextlib import asynccontextmanager
+from typing import Any
 
 from aiohttp import web
 import server
@@ -24,6 +25,12 @@ except ImportError:
             save_config(config)
 from ..utils.logging import debug_log, log
 from ..utils.network import handle_api_error, normalize_host
+from ..utils.secret_fields import is_secret_field_name
+from ..utils.serverless_config import (
+    ServerlessSecretChanges,
+    public_config,
+    validate_serverless_worker,
+)
 
 
 def _positive_int(value):
@@ -86,22 +93,159 @@ def _apply_field_patch(target: dict, data: dict, field_rules: list) -> None:
             target[key] = normalizer(value) if (normalizer and value is not None) else value
 
 
+_SECRET_FIELDS = {"api_key", "clear_api_key"}
+_SERVERLESS_LOCAL_FIELDS = {"host", "port", "listen_port", "cuda_device", "extra_args"}
+_SERVERLESS_ONLY_FIELDS = {
+    "provider", "endpoint_id", "jobs_per_run", "concurrency", "timeout_seconds", "api_key_configured",
+}
+_SERVERLESS_CONFIG_FIELDS = {
+    "worker_id", "type", "provider", "endpoint_id", "jobs_per_run", "concurrency",
+    "timeout_seconds", "enabled", "name", "api_key", "clear_api_key",
+}
+
+
+class _ActivePoolCheckError(RuntimeError):
+    pass
+
+
+def _error_response(message, status):
+    return web.json_response({"status": "error", "message": message}, status=status)
+
+
+def _contains_secret_fields(value, *, allow_root_serverless_secrets=False, depth=0):
+    if isinstance(value, dict):
+        for key, item in value.items():
+            field_name = key.casefold() if isinstance(key, str) else ""
+            if is_secret_field_name(field_name):
+                if not (allow_root_serverless_secrets and depth == 0 and key in _SECRET_FIELDS):
+                    return True
+            if _contains_secret_fields(
+                item, allow_root_serverless_secrets=allow_root_serverless_secrets, depth=depth + 1
+            ):
+                return True
+    elif isinstance(value, (list, tuple)):
+        return any(
+            _contains_secret_fields(
+                item, allow_root_serverless_secrets=allow_root_serverless_secrets, depth=depth + 1
+            )
+            for item in value
+        )
+    return False
+
+
+def _serverless_secret_store():
+    from .orchestration.serverless_runtime import get_secret_store
+    return get_secret_store()
+
+
+def _serverless_pool_is_active(worker_id):
+    from .orchestration.serverless_runtime import get_manager
+    return get_manager().pool_is_active(worker_id)
+
+
+def _ensure_pool_idle(worker_id):
+    try:
+        active = _serverless_pool_is_active(worker_id)
+    except Exception:
+        raise _ActivePoolCheckError from None
+    if active:
+        raise _ActivePoolCheckError
+
+
+def _worker_by_id(workers, worker_id):
+    for worker in workers:
+        if isinstance(worker, dict) and worker.get("id") == worker_id:
+            return worker
+    return None
+
+
+def _worker_type(worker):
+    return worker.get("type", "local") if isinstance(worker, dict) else None
+
+
+def _strip_sensitive_fields(value: Any) -> Any:
+    if isinstance(value, dict):
+        return {
+            key: _strip_sensitive_fields(item)
+            for key, item in value.items()
+            if not is_secret_field_name(key)
+        }
+    if isinstance(value, list):
+        return [_strip_sensitive_fields(item) for item in value]
+    return value
+
+
+def _clean_serverless_worker(worker):
+    clean = _strip_sensitive_fields(dict(worker))
+    for field in _SERVERLESS_LOCAL_FIELDS | {"api_key_configured"}:
+        clean.pop(field, None)
+    return clean
+
+
+def _validate_bulk_workers(workers):
+    validated = []
+    for worker in workers:
+        if isinstance(worker, dict) and worker.get("type") == "serverless":
+            clean = _clean_serverless_worker(worker)
+            validated.append(validate_serverless_worker(clean))
+        else:
+            validated.append(worker)
+    return validated
+
+
+def _clean_bulk_type_conversions(old_workers, new_workers):
+    old_by_id = {str(w.get("id")): w for w in old_workers if isinstance(w, dict) and w.get("id") is not None}
+    for index, worker in enumerate(new_workers):
+        if not isinstance(worker, dict) or worker.get("id") is None:
+            continue
+        old = old_by_id.get(str(worker["id"]))
+        if old is None or old.get("type") != "serverless" or worker.get("type") == "serverless":
+            continue
+        converted = dict(worker)
+        for field in _SERVERLESS_ONLY_FIELDS:
+            converted.pop(field, None)
+        new_workers[index] = converted
+    return new_workers
+
+
+def _bulk_serverless_changes(old_workers, new_workers):
+    old_by_id = {str(w.get("id")): w for w in old_workers if isinstance(w, dict) and w.get("id") is not None}
+    new_by_id = {str(w.get("id")): w for w in new_workers if isinstance(w, dict) and w.get("id") is not None}
+    secret_ids = set()
+    for worker_id, old in old_by_id.items():
+        new = new_by_id.get(worker_id)
+        if old.get("type") == "serverless":
+            if new is None or new.get("type") != "serverless":
+                _ensure_pool_idle(worker_id)
+                secret_ids.add(worker_id)
+            elif old.get("endpoint_id") != new.get("endpoint_id"):
+                _ensure_pool_idle(worker_id)
+        elif new is not None and new.get("type") == "serverless":
+            secret_ids.add(worker_id)
+    return secret_ids
+
+
 @server.PromptServer.instance.routes.get("/distributed/config")
 async def get_config_endpoint(request):
-    config = load_config()
-    return web.json_response(config)
+    try:
+        config = load_config()
+        return web.json_response(public_config(config, _serverless_secret_store()))
+    except Exception:
+        return _error_response("Unable to read config", 500)
 
 
 @server.PromptServer.instance.routes.post("/distributed/config")
 async def update_config_endpoint(request):
-    """Bulk config update with schema validation."""
+    """Bulk config update with schema validation and credential redaction."""
     try:
         data = await request.json()
-    except Exception as e:
-        return await handle_api_error(request, f"Invalid JSON payload: {e}", 400)
+    except Exception:
+        return _error_response("Invalid JSON payload", 400)
 
     if not isinstance(data, dict):
-        return await handle_api_error(request, "Config payload must be an object", 400)
+        return _error_response("Config payload must be an object", 400)
+    if _contains_secret_fields(data):
+        return _error_response("API keys cannot be set through bulk config", 400)
 
     validated_settings = {}
     validated_root = {}
@@ -118,9 +262,15 @@ async def update_config_endpoint(request):
             continue
 
         if validator and not validator(value):
-            errors.append(f"{key}: value {value!r} failed validation")
+            errors.append(f"{key}: failed validation")
             continue
 
+        if key == "workers":
+            try:
+                value = _validate_bulk_workers(value)
+            except (TypeError, ValueError):
+                return _error_response("Invalid serverless worker configuration", 400)
+
         if key in _SETTINGS_FIELDS:
             validated_settings[key] = value
         else:
@@ -133,15 +283,41 @@ async def update_config_endpoint(request):
             "message": "; ".join(errors),
         }, status=400)
 
+    store = None
+    response_config = None
     try:
-        async with config_transaction() as config:
-            settings = config.setdefault("settings", {})
-            settings.update(validated_settings)
-            for key, value in validated_root.items():
-                config[key] = value
-            return web.json_response({"status": "success", "config": config})
-    except Exception as e:
-        return await handle_api_error(request, e)
+        with ServerlessSecretChanges() as secret_changes:
+            async with config_transaction() as config:
+                if "workers" in validated_root:
+                    old_workers = config.get("workers", [])
+                    validated_root["workers"] = _clean_bulk_type_conversions(
+                        old_workers, validated_root["workers"]
+                    )
+                    changed_ids = _bulk_serverless_changes(old_workers, validated_root["workers"])
+                    for worker in validated_root["workers"]:
+                        if isinstance(worker, dict) and worker.get("type") == "serverless" and worker.get("enabled", False):
+                            store = store or _serverless_secret_store()
+                            if worker["id"] in changed_ids or not store.has(worker["id"]):
+                                return _error_response("Save an API key before enabling this worker", 400)
+                    if changed_ids:
+                        store = store or _serverless_secret_store()
+                        for worker_id in sorted(changed_ids):
+                            prior_secret = secret_changes.capture(store, worker_id)
+                            if prior_secret is not None:
+                                secret_changes.delete(store, worker_id)
+
+                settings = config.setdefault("settings", {})
+                settings.update(validated_settings)
+                for key, value in validated_root.items():
+                    config[key] = value
+                response_config = public_config(config, store or _serverless_secret_store())
+            response = web.json_response({"status": "success", "config": response_config})
+            secret_changes.commit()
+            return response
+    except _ActivePoolCheckError:
+        return _error_response("Finish or reconcile unresolved serverless jobs before changing this worker", 409)
+    except Exception:
+        return _error_response("Unable to update config", 500)
 
 
 @server.PromptServer.instance.routes.get("/distributed/queue_status/{job_id}")
@@ -164,79 +340,202 @@ async def queue_status_endpoint(request):
 
 @server.PromptServer.instance.routes.post("/distributed/config/update_worker")
 async def update_worker_endpoint(request):
+    return await _run_with_serverless_secret_changes(_update_worker_endpoint, request)
+
+
+async def _run_with_serverless_secret_changes(endpoint, request):
+    with ServerlessSecretChanges() as secret_changes:
+        response = await endpoint(request, secret_changes)
+        if response.status < 400:
+            secret_changes.commit()
+        return response
+
+
+async def _update_worker_endpoint(request, secret_changes):
+    store = None
+    worker_id = None
     try:
-        data = await request.json()
+        try:
+            data = await request.json()
+        except Exception:
+            return _error_response("Invalid JSON payload", 400)
+        if not isinstance(data, dict):
+            return _error_response("Worker payload must be an object", 400)
+
         worker_id = data.get("worker_id")
-        
         if worker_id is None:
-            return await handle_api_error(request, "Missing worker_id", 400)
+            return _error_response("Missing worker_id", 400)
 
+        if _contains_secret_fields(data, allow_root_serverless_secrets=True):
+            return _error_response("Invalid worker credentials", 400)
+
+        result = None
         async with config_transaction() as config:
-            worker_found = False
             workers = config.setdefault("workers", [])
+            existing = _worker_by_id(workers, worker_id)
+            current_type = _worker_type(existing)
+            target_type = data.get("type", current_type or "local")
 
-            for worker in workers:
-                if worker["id"] == worker_id:
-                    _apply_field_patch(worker, data, _WORKER_FIELDS)
-                    worker_found = True
-                    break
+            if target_type == "serverless":
+                unknown = set(data) - _SERVERLESS_CONFIG_FIELDS - _SERVERLESS_LOCAL_FIELDS
+                if unknown:
+                    return _error_response("Unknown serverless worker field", 400)
+                if not isinstance(worker_id, str) or not worker_id.strip():
+                    return _error_response("worker_id must be a non-empty string", 400)
+                if "api_key" in data and not isinstance(data["api_key"], str):
+                    return _error_response("Invalid worker credentials", 400)
+                if "clear_api_key" in data and type(data["clear_api_key"]) is not bool:
+                    return _error_response("Invalid worker credentials", 400)
+                supplied_key = data.get("api_key", "")
+                clear_key = data.get("clear_api_key", False)
+                if supplied_key and clear_key:
+                    return _error_response("Choose either api_key or clear_api_key", 400)
+                if "enabled" in data and type(data["enabled"]) is not bool:
+                    return _error_response("enabled must be a boolean", 400)
+                if "name" in data and not isinstance(data["name"], str):
+                    return _error_response("name must be a string", 400)
 
-            if not worker_found:
-                # If worker not found and all required fields are provided, create new worker
-                if all(key in data for key in ["name", "port", "cuda_device"]):
-                    new_worker = {
-                        "id": worker_id,
-                        "name": data["name"],
-                        "host": normalize_host(data.get("host", "localhost")),
-                        "port": data["port"],
-                        "cuda_device": data["cuda_device"],
-                        "enabled": data.get("enabled", False),
-                        "extra_args": data.get("extra_args", ""),
-                        "type": data.get("type", "local")
-                    }
-                    workers.append(new_worker)
+                candidate = dict(existing or {})
+                candidate["id"] = worker_id
+                candidate["type"] = "serverless"
+                candidate.setdefault("provider", "runpod")
+                candidate.setdefault("enabled", False)
+                # Legacy "concurrency" is accepted (see _SERVERLESS_CONFIG_FIELDS) but ignored.
+                for field in ("provider", "endpoint_id", "jobs_per_run", "timeout_seconds", "enabled", "name"):
+                    if field in data:
+                        candidate[field] = data[field]
+                candidate = _clean_serverless_worker(candidate)
+                validated = validate_serverless_worker(candidate)
+                if "enabled" in validated and type(validated["enabled"]) is not bool:
+                    return _error_response("enabled must be a boolean", 400)
+                if "name" in validated and not isinstance(validated["name"], str):
+                    return _error_response("name must be a string", 400)
+
+                store = _serverless_secret_store()
+                prior_secret = secret_changes.capture(store, worker_id)
+                converting_to_serverless = current_type != "serverless"
+                next_secret = None if converting_to_serverless else prior_secret
+                if supplied_key:
+                    next_secret = supplied_key
+                elif clear_key:
+                    next_secret = None
+
+                endpoint_changed = (
+                    current_type == "serverless"
+                    and existing.get("endpoint_id") != validated.get("endpoint_id")
+                )
+                if current_type == "serverless" and (
+                    endpoint_changed or next_secret != prior_secret
+                ):
+                    _ensure_pool_idle(worker_id)
+
+                if validated.get("enabled", False) and next_secret is None:
+                    return _error_response("Save an API key before enabling this worker; turn the worker off before clearing its key", 400)
+
+                if next_secret != prior_secret:
+                    if next_secret is None:
+                        secret_changes.delete(store, worker_id)
+                    else:
+                        secret_changes.set(store, worker_id, next_secret)
+
+                if existing is None:
+                    workers.append(validated)
                 else:
-                    return await handle_api_error(
-                        request,
-                        f"Worker {worker_id} not found and missing required fields for creation",
-                        404,
-                    )
+                    existing.clear()
+                    existing.update(validated)
+                result = {"status": "success", "api_key_configured": next_secret is not None}
+
+            elif existing is not None:
+                cleaned_existing = _strip_sensitive_fields(existing)
+                existing.clear()
+                existing.update(cleaned_existing)
+                if current_type == "serverless":
+                    if _contains_secret_fields(data):
+                        return _error_response("Invalid worker credentials", 400)
+                    _ensure_pool_idle(worker_id)
+                    store = _serverless_secret_store()
+                    prior_secret = secret_changes.capture(store, worker_id)
+                    if prior_secret is not None:
+                        secret_changes.delete(store, worker_id)
+                    for field in _SERVERLESS_ONLY_FIELDS:
+                        existing.pop(field, None)
+                elif _contains_secret_fields(data):
+                    return _error_response("API keys are only accepted for serverless workers", 400)
+                _apply_field_patch(existing, data, _WORKER_FIELDS)
+                result = {"status": "success"}
+            elif all(key in data for key in ["name", "port", "cuda_device"]):
+                if _contains_secret_fields(data):
+                    return _error_response("API keys are only accepted for serverless workers", 400)
+                new_worker = {
+                    "id": worker_id,
+                    "name": data["name"],
+                    "host": normalize_host(data.get("host", "localhost")),
+                    "port": data["port"],
+                    "cuda_device": data["cuda_device"],
+                    "enabled": data.get("enabled", False),
+                    "extra_args": data.get("extra_args", ""),
+                    "type": data.get("type", "local")
+                }
+                workers.append(new_worker)
+                result = {"status": "success"}
+            else:
+                return _error_response(
+                    "Worker not found and missing required fields for creation", 404
+                )
+
+        return web.json_response(result)
+    except _ActivePoolCheckError:
+        return _error_response("Finish or reconcile unresolved serverless jobs before changing this worker", 409)
+    except ValueError:
+        return _error_response("Invalid worker configuration", 400)
+    except Exception:
+        return _error_response("Unable to update worker configuration", 500)
 
-            return web.json_response({"status": "success"})
-    except Exception as e:
-        return await handle_api_error(request, e, 400)
 
 @server.PromptServer.instance.routes.post("/distributed/config/delete_worker")
 async def delete_worker_endpoint(request):
+    return await _run_with_serverless_secret_changes(_delete_worker_endpoint, request)
+
+
+async def _delete_worker_endpoint(request, secret_changes):
+    store = None
+    worker_id = None
     try:
-        data = await request.json()
+        try:
+            data = await request.json()
+        except Exception:
+            return _error_response("Invalid JSON payload", 400)
+        if not isinstance(data, dict):
+            return _error_response("Worker payload must be an object", 400)
         worker_id = data.get("worker_id")
-        
         if worker_id is None:
-            return await handle_api_error(request, "Missing worker_id", 400)
-            
+            return _error_response("Missing worker_id", 400)
+
+        result = None
         async with config_transaction() as config:
             workers = config.get("workers", [])
-
-            # Find and remove the worker
-            worker_index = -1
-            for i, worker in enumerate(workers):
-                if worker["id"] == worker_id:
-                    worker_index = i
-                    break
-
-            if worker_index == -1:
-                return await handle_api_error(request, f"Worker {worker_id} not found", 404)
-
-            # Remove the worker
-            removed_worker = workers.pop(worker_index)
-
-            return web.json_response({
+            removed = _worker_by_id(workers, worker_id)
+            if removed is None:
+                return _error_response("Worker not found", 404)
+            if _worker_type(removed) == "serverless":
+                _ensure_pool_idle(worker_id)
+                store = _serverless_secret_store()
+                secret_worker_id = str(worker_id)
+                prior_secret = secret_changes.capture(store, secret_worker_id)
+                if prior_secret is not None:
+                    secret_changes.delete(store, secret_worker_id)
+            workers.remove(removed)
+            result = {
                 "status": "success",
-                "message": f"Worker {removed_worker.get('name', worker_id)} deleted"
-            })
-    except Exception as e:
-        return await handle_api_error(request, e, 400)
+                "message": "Worker deleted" if _worker_type(removed) == "serverless"
+                else f"Worker {removed.get('name', worker_id)} deleted",
+            }
+
+        return web.json_response(result)
+    except _ActivePoolCheckError:
+        return _error_response("Finish or reconcile unresolved serverless jobs before changing this worker", 409)
+    except Exception:
+        return _error_response("Unable to delete worker", 500)
 
 @server.PromptServer.instance.routes.post("/distributed/config/update_setting")
 async def update_setting_endpoint(request):

api/job_routes.py

@@ -15,6 +15,7 @@ from ..utils.logging import debug_log
 from ..utils.image import pil_to_tensor, ensure_contiguous
 from ..utils.network import handle_api_error
 from ..utils.constants import JOB_INIT_GRACE_PERIOD, MEMORY_CLEAR_DELAY
+from ..utils import transfer_codec
 try:
     from .queue_orchestration import ensure_distributed_state, orchestrate_distributed_execution
 except ImportError:
@@ -26,8 +27,16 @@ from .queue_request import parse_queue_request_payload
 
 prompt_server = server.PromptServer.instance
 
-# Canonical worker result envelope accepted by POST /distributed/job_complete:
-# { "job_id": str, "worker_id": str, "batch_idx": int, "image": <base64 PNG>, "is_last": bool }
+# Worker result envelopes accepted by POST /distributed/job_complete:
+#
+# application/json (legacy, one frame per request):
+#   { "job_id": str, "worker_id": str, "batch_idx": int, "image": <base64 PNG>, "is_last": bool,
+#     "audio"?: {...} }
+#
+# multipart/form-data (compressed, many frames per request):
+#   envelope: JSON { "job_id", "worker_id", "format", "start_index", "count", "width", "height",
+#                    "is_last", "audio"?: {...} }
+#   media:    one part per frame for still formats, or one video file for video formats
 
 
 def _decode_image_sync(image_path):
@@ -270,8 +279,136 @@ async def check_file_endpoint(request):
         return await handle_api_error(request, e, 500)
 
 
+async def _enqueue_worker_items(multi_job_id, items):
+    """Put decoded items on the job queue, waiting briefly for the master to create it.
+
+    Returns the queue size after enqueueing, or None if the job never appeared.
+    """
+    deadline = time.monotonic() + float(JOB_INIT_GRACE_PERIOD)
+    while True:
+        async with prompt_server.distributed_jobs_lock:
+            pending = prompt_server.distributed_pending_jobs.get(multi_job_id)
+            if pending is not None:
+                for item in items:
+                    await pending.put(item)
+                return pending.qsize()
+        if time.monotonic() > deadline:
+            return None
+        await asyncio.sleep(0.05)
+
+
+def _decode_compressed_chunk_sync(envelope, parts):
+    """Decode a compressed chunk into per-frame IMAGE tensors (threadpool)."""
+    frames = transfer_codec.decode_chunk(envelope, parts)
+    return [
+        ensure_contiguous(torch.from_numpy(transfer_codec.uint8_frame_to_tensor_array(frame)))
+        for frame in frames
+    ]
+
+
+def _validate_compressed_envelope(envelope):
+    errors = []
+    if not isinstance(envelope, dict):
+        return ["envelope: expected JSON object"]
+    for key in ("job_id", "worker_id"):
+        value = envelope.get(key)
+        if not isinstance(value, str) or not value.strip():
+            errors.append(f"{key}: expected non-empty string")
+    start_index = envelope.get("start_index")
+    if not isinstance(start_index, int) or isinstance(start_index, bool) or start_index < 0:
+        errors.append("start_index: expected non-negative integer")
+    if not isinstance(envelope.get("is_last"), bool):
+        errors.append("is_last: expected boolean")
+    try:
+        if transfer_codec.normalize_format(envelope.get("format")) == transfer_codec.LEGACY_FORMAT:
+            errors.append("format: legacy_png must be sent as JSON")
+    except transfer_codec.TransferCodecError as exc:
+        errors.append(f"format: {exc}")
+    audio_payload = envelope.get("audio")
+    if audio_payload is not None and not isinstance(audio_payload, dict):
+        errors.append("audio: expected object when provided")
+    return errors
+
+
+async def _job_complete_compressed(request):
+    try:
+        form = await request.post()
+    except Exception as exc:
+        too_large = getattr(web, "HTTPRequestEntityTooLarge", None)
+        if too_large is not None and isinstance(exc, too_large):
+            return await handle_api_error(
+                request, f"Request body exceeds the master's upload limit (--max-upload-size): {exc}", 413)
+        return await handle_api_error(request, f"Invalid multipart payload: {exc}", 400)
+
+    raw_envelope = form.get("envelope")
+    if isinstance(raw_envelope, (bytes, bytearray)):
+        raw_envelope = raw_envelope.decode("utf-8")
+    elif hasattr(raw_envelope, "file"):
+        raw_envelope = raw_envelope.file.read().decode("utf-8")
+    try:
+        envelope = json.loads(raw_envelope) if isinstance(raw_envelope, str) else None
+    except ValueError as exc:
+        return await handle_api_error(request, f"envelope: invalid JSON ({exc})", 400)
+    if envelope is None:
+        return await handle_api_error(request, "envelope: missing field", 400)
+
+    errors = _validate_compressed_envelope(envelope)
+    if errors:
+        return await handle_api_error(request, errors, 400)
+
+    parts = []
+    for field in form.getall("media", []):
+        if hasattr(field, "file"):
+            parts.append(field.file.read())
+        elif isinstance(field, (bytes, bytearray)):
+            parts.append(bytes(field))
+        else:
+            return await handle_api_error(request, "media: expected binary file parts", 400)
+
+    loop = asyncio.get_running_loop()
+    try:
+        tensors = await loop.run_in_executor(None, _decode_compressed_chunk_sync, envelope, parts)
+        decoded_audio = _decode_audio_payload(envelope.get("audio")) if envelope.get("audio") is not None else None
+    except ValueError as exc:
+        return await handle_api_error(request, exc, 400)
+
+    multi_job_id = envelope["job_id"].strip()
+    worker_id = envelope["worker_id"].strip()
+    start_index = envelope["start_index"]
+    is_last = envelope["is_last"]
+    last_pos = len(tensors) - 1
+    items = [
+        {
+            "tensor": tensor,
+            "worker_id": worker_id,
+            "image_index": start_index + pos,
+            "is_last": bool(is_last and pos == last_pos),
+            "audio": decoded_audio if pos == last_pos else None,
+        }
+        for pos, tensor in enumerate(tensors)
+    ]
+
+    queue_size = await _enqueue_worker_items(multi_job_id, items)
+    if queue_size is None:
+        return await handle_api_error(request, "job not initialized", 404)
+
+    debug_log(
+        f"job_complete received {envelope['format']} chunk - job_id: {multi_job_id}, worker: {worker_id}, "
+        f"frames: {start_index}..{start_index + len(items) - 1}, "
+        f"bytes: {sum(len(p) for p in parts)}, is_last: {is_last}, queue_size: {queue_size}"
+    )
+    return web.json_response({"status": "success", "frames": len(items)})
+
+
 @server.PromptServer.instance.routes.post("/distributed/job_complete")
 async def job_complete_endpoint(request):
+    content_type = str(getattr(request, "content_type", "") or "").lower()
+    if content_type.startswith("multipart/"):
+        try:
+            return await _job_complete_compressed(request)
+        except Exception as e:
+            return await handle_api_error(request, e)
+
     try:
         data = await request.json()
     except Exception as exc:
@@ -316,28 +453,20 @@ async def job_complete_endpoint(request):
         multi_job_id = job_id.strip()
         worker_id = worker_id.strip()
 
-        pending = None
-        queue_size = 0
-        deadline = time.monotonic() + float(JOB_INIT_GRACE_PERIOD)
-        while pending is None:
-            async with prompt_server.distributed_jobs_lock:
-                pending = prompt_server.distributed_pending_jobs.get(multi_job_id)
-                if pending is not None:
-                    await pending.put(
-                        {
-                            "tensor": tensor,
-                            "worker_id": worker_id,
-                            "image_index": int(batch_idx),
-                            "is_last": is_last,
-                            "audio": decoded_audio,
-                        }
-                    )
-                    queue_size = pending.qsize()
-                    break
-
-            if time.monotonic() > deadline:
-                return await handle_api_error(request, "job not initialized", 404)
-            await asyncio.sleep(0.05)
+        queue_size = await _enqueue_worker_items(
+            multi_job_id,
+            [
+                {
+                    "tensor": tensor,
+                    "worker_id": worker_id,
+                    "image_index": int(batch_idx),
+                    "is_last": is_last,
+                    "audio": decoded_audio,
+                }
+            ],
+        )
+        if queue_size is None:
+            return await handle_api_error(request, "job not initialized", 404)
 
         debug_log(
             f"job_complete received canonical envelope - job_id: {multi_job_id}, "

api/orchestration/dispatch.py

@@ -55,6 +55,11 @@ async def worker_ws_is_active(worker):
 
 async def _probe_worker_active(worker, use_websocket, semaphore):
     async with semaphore:
+        if worker.get("type") == "serverless":
+            from .serverless_runtime import get_manager
+            # Authentication/configuration failures must surface, not silently skip paid work.
+            status = await get_manager().health(worker)
+            return worker, status["ok"]
         is_active = await (worker_ws_is_active(worker) if use_websocket else worker_is_active(worker))
         return worker, is_active
 
@@ -203,6 +208,10 @@ def _extract_queue_remaining(payload):
 
 async def _probe_worker_queue(worker, semaphore, probe_timeout):
     async with semaphore:
+        if worker.get("type") == "serverless":
+            from .serverless_runtime import get_manager
+            status = await get_manager().health(worker)
+            return {"worker": worker, "queue_remaining": status["queueRemaining"]}
         worker_url = build_worker_url(worker)
         payload = await probe_worker(worker_url, timeout=probe_timeout)
         if payload is None:

api/orchestration/media_sync.py

@@ -143,6 +143,30 @@ async def fetch_worker_path_separator(worker, trace_execution_id=None):
         return None
 
 
+async def fetch_worker_has_node(worker, node_class, trace_execution_id=None):
+    """Best-effort check that a worker has ``node_class`` registered.
+
+    Uses ComfyUI's ``GET /object_info/{node_class}``, which returns ``{}`` for
+    unknown classes. Any failure counts as "not available" so callers fall
+    back to nodes every ComfyUI install has.
+    """
+    url = build_worker_url(worker, f"/object_info/{node_class}")
+    session = await get_client_session()
+    try:
+        async with session.get(url, timeout=aiohttp.ClientTimeout(total=5)) as resp:
+            if resp.status != 200:
+                return False
+            payload = await resp.json()
+            return isinstance(payload, dict) and node_class in payload
+    except Exception as exc:
+        message = f"Failed to probe node '{node_class}' on worker {worker.get('id')}: {exc}"
+        if trace_execution_id:
+            trace_debug(trace_execution_id, message)
+        else:
+            debug_log(f"[Distributed] {message}")
+        return False
+
+
 async def _upload_media_to_worker(worker, filename, file_bytes, file_hash, mime_type, trace_execution_id=None):
     """Upload one media file to worker iff missing or hash-mismatched."""
     session = await get_client_session()

api/orchestration/prompt_transform.py

@@ -328,8 +328,19 @@ def _find_delegate_master_retained_upstream_nodes(prompt_obj, start_ids):
     return connected
 
 
-def prune_prompt_for_worker(prompt_obj):
-    """Prune worker prompt to distributed nodes and their upstream dependencies."""
+WORKER_SINK_CLASS = "DistributedWorkerSink"
+
+
+def prune_prompt_for_worker(prompt_obj, use_worker_sink=False):
+    """Prune worker prompt to distributed nodes and their upstream dependencies.
+
+    Removing downstream nodes can leave the worker prompt without an output
+    node. One is re-added after each such distributed node: the hidden
+    ``DistributedWorkerSink`` when ``use_worker_sink`` is set (the worker must
+    have it registered), otherwise PreviewImage/PreviewAudio for workers
+    running older versions. The preview nodes write every frame to the
+    worker's temp directory, which the sink avoids.
+    """
     collector_ids = find_nodes_by_class(prompt_obj, "DistributedCollector")
     upscale_ids = find_nodes_by_class(prompt_obj, "UltimateSDUpscaleDistributed")
     distributed_ids = collector_ids + upscale_ids
@@ -364,7 +375,13 @@ def prune_prompt_for_worker(prompt_obj):
                 and len(inputs["audio"]) == 2
             )
 
-            if image_connected:
+            if use_worker_sink and (image_connected or audio_connected):
+                pruned_prompt[next_id()] = {
+                    "inputs": {"value": [dist_id, 0 if image_connected else 1]},
+                    "class_type": WORKER_SINK_CLASS,
+                    "_meta": {"title": "Distributed Worker Sink (auto-added)"},
+                }
+            elif image_connected:
                 preview_id = next_id()
                 pruned_prompt[preview_id] = {
                     "inputs": {"images": [dist_id, 0]},

api/orchestration/runpod_client.py

@@ -0,0 +1,123 @@
+"""Small Runpod queue API client. Never retries a potentially billable POST."""
+import asyncio
+import json
+import re
+
+import aiohttp
+
+API_BASE = "https://api.runpod.ai/v2"
+MAX_REQUEST_BYTES = 10_000_000
+_ID = re.compile(r"[A-Za-z0-9_-]{1,200}\Z")
+
+
+class RunpodError(RuntimeError):
+    """Sanitized provider failure safe to display in the panel."""
+
+
+class AmbiguousSubmission(RunpodError):
+    """Submission may have been accepted: never retry it automatically."""
+
+
+def serialize_request(workflow, images, timeout_seconds):
+    """Serialize and size-check the exact JSON body used by Runpod ``/run``."""
+    payload = {
+        "input": {"workflow": workflow, "images": images},
+        "policy": {
+            "executionTimeout": timeout_seconds * 1000,
+            "ttl": timeout_seconds * 1000,
+        },
+    }
+    body = json.dumps(
+        payload,
+        allow_nan=False,
+        ensure_ascii=False,
+        separators=(",", ":"),
+    ).encode("utf-8")
+    size = len(body)
+    if size > MAX_REQUEST_BYTES:
+        raise ValueError(
+            f"Serialized serverless request body is {size:,} bytes; Runpod allows at most "
+            f"{MAX_REQUEST_BYTES:,} bytes. Base64-encoded images add about 33% over raw "
+            "image bytes; reduce image or workflow size."
+        )
+    return body
+
+
+def checked_id(value):
+    if not isinstance(value, str) or not _ID.fullmatch(value):
+        raise ValueError("Invalid Runpod endpoint or job ID")
+    return value
+
+
+class RunpodClient:
+    def __init__(self, session, endpoint_id, api_key):
+        self.session = session
+        self.endpoint_id = checked_id(endpoint_id)
+        if not isinstance(api_key, str) or not api_key or any(c in api_key for c in "\r\n"):
+            raise ValueError("A valid Runpod API key is required")
+        self._api_key = api_key
+
+    async def _request(self, method, path, payload=None, request_body=None):
+        # Base origin is code-owned, never a user-supplied URL. Do not follow redirects
+        # with credentials, or include response bodies/transport errors in exceptions.
+        url = f"{API_BASE}/{self.endpoint_id}/{path}"
+        attempts = 3 if method == "GET" else 1
+        for attempt in range(attempts):
+            try:
+                request_kwargs = {
+                    "headers": {"Authorization": f"Bearer {self._api_key}", "Content-Type": "application/json"},
+                    "timeout": aiohttp.ClientTimeout(total=30),
+                    "allow_redirects": False,
+                }
+                if request_body is None:
+                    request_kwargs["json"] = payload
+                else:
+                    request_kwargs["data"] = request_body
+                async with self.session.request(
+                    method, url,
+                    **request_kwargs,
+                ) as response:
+                    status = response.status
+                    if status != 200:
+                        if method == "GET" and (status == 429 or status >= 500) and attempt + 1 < attempts:
+                            await asyncio.sleep(0.5 * (2 ** attempt))
+                            continue
+                        if method == "POST" and path == "run" and status >= 500:
+                            raise AmbiguousSubmission("Runpod submission returned a server error; acceptance is unknown. Check the provider before retrying.")
+                        raise RunpodError(f"Runpod {path.split('/')[0]} request failed (HTTP {status})")
+                    try:
+                        result = await response.json()
+                    except (ValueError, aiohttp.ContentTypeError):
+                        if method == "POST" and path == "run":
+                            raise AmbiguousSubmission("Runpod submission returned an unreadable response; check the provider before retrying.") from None
+                        raise RunpodError("Runpod returned an invalid JSON response") from None
+                    if not isinstance(result, dict):
+                        if method == "POST" and path == "run":
+                            raise AmbiguousSubmission("Runpod submission did not return a job record; check the provider before retrying.")
+                        raise RunpodError("Runpod returned an invalid response")
+                    return result
+            except (asyncio.TimeoutError, aiohttp.ClientError, OSError):
+                if method == "POST" and path == "run":
+                    raise AmbiguousSubmission("Runpod submission connection was interrupted; acceptance is unknown. Check the provider before retrying.") from None
+                if method == "GET" and attempt + 1 < attempts:
+                    await asyncio.sleep(0.5 * (2 ** attempt))
+                    continue
+                raise RunpodError(f"Runpod {path.split('/')[0]} connection failed") from None
+        raise RunpodError("Runpod request failed")
+
+    async def health(self):
+        return await self._request("GET", "health")
+
+    async def submit(self, workflow, images, timeout_seconds):
+        body = serialize_request(workflow, images, timeout_seconds)
+        result = await self._request("POST", "run", request_body=body)
+        try:
+            return checked_id(result.get("id"))
+        except ValueError:
+            raise AmbiguousSubmission("Runpod submission returned no valid job ID; check the provider before retrying.") from None
+
+    async def status(self, job_id):
+        return await self._request("GET", f"status/{checked_id(job_id)}")
+
+    async def cancel(self, job_id):
+        return await self._request("POST", f"cancel/{checked_id(job_id)}")

api/orchestration/serverless_ledger.py

@@ -0,0 +1,57 @@
+"""Private, atomic job-ID journal. Contains identifiers/status only, never payloads."""
+import json
+import os
+from pathlib import Path
+import tempfile
+import threading
+
+from .serverless_state import TERMINAL
+FIELDS = {"record_id", "execution_id", "worker_id", "participant_id", "endpoint_id", "job_id", "status", "created_at", "updated_at", "error", "prompt_id"}
+
+
+class JobLedger:
+    def __init__(self, path):
+        self.path = Path(path)
+        self._lock = threading.RLock()
+
+    def _read(self):
+        if self.path.is_symlink():
+            raise RuntimeError("Unsafe serverless job journal path")
+        if not self.path.exists():
+            return {}
+        try:
+            data = json.loads(self.path.read_text(encoding="utf-8"))
+            if not isinstance(data, dict) or any(not isinstance(v, dict) or set(v) - FIELDS for v in data.values()):
+                raise ValueError()
+            return data
+        except (ValueError, OSError):
+            raise RuntimeError("Serverless job journal is unreadable; preserve it for recovery before submitting more work") from None
+
+    def all(self):
+        with self._lock:
+            return list(self._read().values())
+
+    def update(self, record_id, **fields):
+        if set(fields) - FIELDS:
+            raise ValueError("Unexpected serverless journal field")
+        with self._lock:
+            data = self._read()
+            data.setdefault(record_id, {"record_id": record_id}).update(fields)
+            # Keep every unresolved job, plus a bounded terminal history.
+            completed = sorted((k for k, v in data.items() if v.get("status") in TERMINAL), key=lambda k: data[k].get("updated_at", 0))
+            for key in completed[:-200]:
+                data.pop(key)
+            if self.path.parent.is_symlink():
+                raise RuntimeError("Unsafe serverless journal directory")
+            self.path.parent.mkdir(mode=0o700, parents=True, exist_ok=True)
+            fd, temporary = tempfile.mkstemp(prefix=".jobs-", dir=self.path.parent)
+            try:
+                with os.fdopen(fd, "w", encoding="utf-8") as stream:
+                    json.dump(data, stream, allow_nan=False)
+                    stream.flush()
+                    os.fsync(stream.fileno())
+                os.replace(temporary, self.path)
+            finally:
+                if os.path.exists(temporary):
+                    os.unlink(temporary)
+            return dict(data[record_id])

api/orchestration/serverless_media.py

@@ -0,0 +1,601 @@
+"""Bounded image transport for generic Runpod-backed ComfyUI jobs."""
+
+import asyncio
+import base64
+import binascii
+import hashlib
+import io
+import ipaddress
+import os
+import re
+import socket
+import stat
+import warnings
+from pathlib import Path, PurePosixPath
+from urllib.parse import urljoin, urlsplit
+
+import aiohttp
+import numpy as np
+from PIL import Image, UnidentifiedImageError
+
+
+MAX_INPUT_IMAGE_BYTES = 25 * 1024 * 1024
+MAX_INPUT_TOTAL_BYTES = 10_000_000
+MAX_OUTPUT_FILES = 1024
+MAX_OUTPUT_IMAGE_BYTES = 128 * 1024 * 1024
+MAX_OUTPUT_TOTAL_BYTES = 256 * 1024 * 1024
+MAX_IMAGE_PIXELS = 40_000_000
+MAX_OUTPUT_ARRAY_BYTES = 256 * 1024 * 1024
+MAX_REDIRECTS = 3
+_DOWNLOAD_TIMEOUT_SECONDS = 60
+_CHUNK_SIZE = 64 * 1024
+
+_IMAGE_EXTENSIONS = {".png", ".jpg", ".jpeg", ".webp", ".bmp"}
+_UNSUPPORTED_IMAGE_EXTENSIONS = {".gif", ".tif", ".tiff", ".avif", ".heic", ".ico", ".svg"}
+_AUDIO_EXTENSIONS = {".wav", ".mp3", ".flac", ".m4a", ".aac", ".ogg", ".opus", ".aiff", ".aif", ".wma"}
+_VIDEO_EXTENSIONS = {".mp4", ".avi", ".mov", ".mkv", ".webm"}
+_MEDIA_EXTENSIONS = _IMAGE_EXTENSIONS | _UNSUPPORTED_IMAGE_EXTENSIONS | _AUDIO_EXTENSIONS | _VIDEO_EXTENSIONS
+_MEDIA_ANNOTATION = re.compile(r"\s+\[([A-Za-z0-9_-]{1,64})\]$")
+_PREFIX_RE = re.compile(r"[A-Za-z0-9][A-Za-z0-9_.-]{0,199}\Z", re.ASCII)
+_SAFE_FILENAME_RE = re.compile(r"[A-Za-z0-9_.-]{1,255}\Z", re.ASCII)
+
+
+class ServerlessMediaError(ValueError):
+    """Sanitized input, artifact, or download validation failure."""
+
+
+def _folder_roots(folder_paths):
+    roots = {}
+    for kind, getter_name in (
+        ("input", "get_input_directory"),
+        ("output", "get_output_directory"),
+        ("temp", "get_temp_directory"),
+    ):
+        getter = getattr(folder_paths, getter_name, None)
+        if not callable(getter):
+            raise ServerlessMediaError("ComfyUI media directories are unavailable")
+        try:
+            roots[kind] = Path(getter()).resolve(strict=True)
+        except Exception:
+            raise ServerlessMediaError("ComfyUI media directories are unavailable") from None
+    return roots
+
+
+def _inside_roots(path, roots):
+    for root in roots.values():
+        try:
+            path.relative_to(root)
+            return True
+        except ValueError:
+            continue
+    return False
+
+
+def _normalize_media_reference(value):
+    if not isinstance(value, str) or not value or value != value.strip() or "\x00" in value:
+        raise ServerlessMediaError("Image input reference is invalid")
+    value = value.replace("\\", "/")
+    explicit_root = None
+    annotation = _MEDIA_ANNOTATION.search(value)
+    if annotation:
+        marker = annotation.group(1).lower()
+        if marker not in {"input", "output", "temp"}:
+            raise ServerlessMediaError("Image input annotation is unsupported")
+        explicit_root = marker
+        value = value[: annotation.start()]
+    if "://" in value:
+        raise ServerlessMediaError("Remote media references are not supported as image inputs")
+    if re.match(r"^[A-Za-z]:", value) or value.startswith("//"):
+        raise ServerlessMediaError("Image input path is outside the allowed ComfyUI media directories")
+
+    path = PurePosixPath(value)
+    if any(part == ".." for part in path.parts):
+        raise ServerlessMediaError("Image input path traversal is not allowed")
+    if not path.parts or value in {".", ""}:
+        raise ServerlessMediaError("Image input reference is invalid")
+
+    if explicit_root:
+        value = f"{value} [{explicit_root}]"
+    suffix = Path(path.name).suffix.lower()
+    return value, suffix
+
+
+def _resolve_input_path(value, suffix, folder_paths, roots):
+    if suffix not in _IMAGE_EXTENSIONS:
+        if suffix in _MEDIA_EXTENSIONS:
+            raise ServerlessMediaError("Audio and video inputs are not supported by serverless image transport")
+        raise ServerlessMediaError("Unsupported serverless image file type")
+
+    try:
+        source = Path(value)
+        if source.is_absolute():
+            annotation = _MEDIA_ANNOTATION.search(value)
+            unannotated = value[:annotation.start()] if annotation else value
+            resolved = Path(unannotated).resolve(strict=True)
+        else:
+            resolver = getattr(folder_paths, "get_annotated_filepath", None)
+            if not callable(resolver):
+                raise ServerlessMediaError("ComfyUI media path resolver is unavailable")
+            resolved = Path(resolver(value)).resolve(strict=True)
+    except ServerlessMediaError:
+        raise
+    except Exception:
+        raise ServerlessMediaError("Image input file is missing or invalid") from None
+
+    if not _inside_roots(resolved, roots):
+        raise ServerlessMediaError("Image input path is outside the allowed ComfyUI media directories")
+    try:
+        mode = resolved.stat().st_mode
+    except OSError:
+        raise ServerlessMediaError("Image input file is missing or invalid") from None
+    if not stat.S_ISREG(mode):
+        raise ServerlessMediaError("Image input is not a regular file")
+    return resolved
+
+
+def _iter_image_references(workflow):
+    if not isinstance(workflow, dict):
+        raise ServerlessMediaError("Serverless workflow must be an API graph")
+    references = []
+    for node_id, node in workflow.items():
+        if not isinstance(node, dict):
+            continue
+        class_type = node.get("class_type")
+        inputs = node.get("inputs", {})
+        if class_type == "LoadImage" and not isinstance(inputs, dict):
+            raise ServerlessMediaError("LoadImage requires a literal image filename; linked image inputs are unsupported")
+        if not isinstance(inputs, dict):
+            continue
+        if class_type == "LoadImage":
+            value = inputs.get("image")
+            if not isinstance(value, str):
+                raise ServerlessMediaError("LoadImage requires a literal image filename; linked image inputs are unsupported")
+            references.append((node_id, inputs, "image", value, True))
+
+        for key in ("image", "file"):
+            if key == "image" and class_type == "LoadImage":
+                continue
+            value = inputs.get(key)
+            if not isinstance(value, str):
+                continue
+            normalized, suffix = _normalize_media_reference(value)
+            if suffix in _IMAGE_EXTENSIONS:
+                references.append((node_id, inputs, key, normalized, False))
+            elif suffix in _AUDIO_EXTENSIONS | _VIDEO_EXTENSIONS:
+                raise ServerlessMediaError("Audio and video inputs are not supported by serverless image transport")
+            elif suffix in _UNSUPPORTED_IMAGE_EXTENSIONS or (key == "image" and suffix):
+                raise ServerlessMediaError("Unsupported serverless image file type")
+
+        for key in ("audio", "video"):
+            value = inputs.get(key)
+            if not isinstance(value, str):
+                continue
+            _normalized, suffix = _normalize_media_reference(value)
+            if suffix in _MEDIA_EXTENSIONS:
+                raise ServerlessMediaError("Audio and video inputs are not supported by serverless image transport")
+    return references
+
+
+def _read_limited(path, expected_size):
+    try:
+        descriptor = os.open(path, os.O_RDONLY | getattr(os, "O_NOFOLLOW", 0))
+        with os.fdopen(descriptor, "rb") as handle:
+            info = os.fstat(handle.fileno())
+            if not stat.S_ISREG(info.st_mode) or info.st_size > MAX_INPUT_IMAGE_BYTES:
+                raise ServerlessMediaError("Image input exceeds the permitted size")
+            if info.st_size > MAX_INPUT_TOTAL_BYTES:
+                raise ServerlessMediaError(
+                    f"Total raw serverless image input size exceeds {MAX_INPUT_TOTAL_BYTES:,} bytes; "
+                    "base64 encoding adds about 33%, and the complete request body is also limited to 10,000,000 bytes"
+                )
+            data = handle.read(MAX_INPUT_TOTAL_BYTES + 1)
+    except ServerlessMediaError:
+        raise
+    except OSError:
+        raise ServerlessMediaError("Image input file could not be read safely") from None
+    if len(data) > MAX_INPUT_TOTAL_BYTES:
+        raise ServerlessMediaError(
+            f"Total raw serverless image input size exceeds {MAX_INPUT_TOTAL_BYTES:,} bytes; "
+            "base64 encoding adds about 33%, and the complete request body is also limited to 10,000,000 bytes"
+        )
+    if len(data) != expected_size:
+        raise ServerlessMediaError("Image input changed while being read")
+    return data
+
+
+async def prepare_images(workflow: dict) -> list[dict]:
+    """Pack referenced local images and rewrite only their graph input references.
+
+    ``workflow`` is expected to be a private API-graph copy owned by the caller.
+    Returned ``name`` values are flat generated names suitable for ``input.images``.
+    """
+    references = _iter_image_references(workflow)
+    if not references:
+        return []
+
+    # Import only in ComfyUI, keeping this module importable in the serverless client.
+    try:
+        import folder_paths
+    except Exception:
+        raise ServerlessMediaError("ComfyUI media directories are unavailable") from None
+
+    roots = _folder_roots(folder_paths)
+    resolved_refs = []
+    unique_paths = {}
+    total_source_bytes = 0
+    for node_id, inputs, key, value, _is_load_image in references:
+        normalized, suffix = _normalize_media_reference(value)
+        if key == "image" and suffix not in _IMAGE_EXTENSIONS:
+            if suffix in _AUDIO_EXTENSIONS | _VIDEO_EXTENSIONS:
+                raise ServerlessMediaError("Audio and video inputs are not supported by serverless image transport")
+            raise ServerlessMediaError("Unsupported serverless image file type")
+        path = _resolve_input_path(normalized, suffix, folder_paths, roots)
+        if path not in unique_paths:
+            try:
+                size = path.stat().st_size
+            except OSError:
+                raise ServerlessMediaError("Image input file is missing or invalid") from None
+            if size < 0 or size > MAX_INPUT_IMAGE_BYTES:
+                raise ServerlessMediaError("Image input exceeds the permitted size")
+            total_source_bytes += size
+            if total_source_bytes > MAX_INPUT_TOTAL_BYTES:
+                raise ServerlessMediaError(
+                    f"Total raw serverless image input size is {total_source_bytes:,} bytes; "
+                    f"the input read guard is {MAX_INPUT_TOTAL_BYTES:,} bytes. Base64 encoding "
+                    "adds about 33%, and the complete request body is also limited to 10,000,000 bytes"
+                )
+            unique_paths[path] = {"size": size, "suffix": suffix}
+        resolved_refs.append((inputs, key, path))
+
+    packed_by_name = {}
+    path_to_name = {}
+    for path, metadata in unique_paths.items():
+        data = _read_limited(path, metadata["size"])
+        digest = hashlib.sha256(data).hexdigest()
+        name = f"serverless_{digest}{metadata['suffix']}"
+        path_to_name[path] = name
+        packed_by_name.setdefault(name, {"name": name, "image": base64.b64encode(data).decode("ascii")})
+
+    for inputs, key, path in resolved_refs:
+        inputs[key] = path_to_name[path]
+    return [packed_by_name[name] for name in sorted(packed_by_name)]
+
+
+def _validate_artifact_url(url):
+    if not isinstance(url, str) or not url or any(ord(char) < 0x20 or char.isspace() for char in url):
+        raise ServerlessMediaError("Serverless image artifact URL is invalid")
+    try:
+        parsed = urlsplit(url)
+        port = parsed.port
+    except ValueError:
+        raise ServerlessMediaError("Serverless image artifact URL is invalid") from None
+    if (
+        parsed.scheme.lower() != "https"
+        or not parsed.hostname
+        or parsed.username is not None
+        or parsed.password is not None
+        or port not in (None, 443)
+        or parsed.fragment
+    ):
+        raise ServerlessMediaError("Serverless image artifact URL must be a public HTTPS URL")
+    host = parsed.hostname.rstrip(".").lower()
+    if host in {"localhost", "metadata", "metadata.google.internal"} or host.endswith((".localhost", ".local", ".internal")):
+        raise ServerlessMediaError("Serverless image artifact URL must be a public HTTPS URL")
+    try:
+        address = ipaddress.ip_address(host)
+    except ValueError:
+        return url
+    if not address.is_global:
+        raise ServerlessMediaError("Serverless image artifact URL must resolve to a public address")
+    return url
+
+
+class _PublicResolver(aiohttp.abc.AbstractResolver):
+    """Resolve once, reject non-public answers, and pin the checked address."""
+
+    async def _getaddrinfo(self, host, port, family):
+        return await asyncio.get_running_loop().getaddrinfo(
+            host, port, family=family, type=socket.SOCK_STREAM
+        )
+
+    async def resolve(self, host, port=0, family=socket.AF_INET):
+        try:
+            results = await self._getaddrinfo(host, port, family)
+        except (OSError, asyncio.TimeoutError):
+            raise OSError("Public artifact host could not be resolved") from None
+        if not results:
+            raise OSError("Public artifact host could not be resolved")
+
+        resolved = []
+        seen = set()
+        for result_family, _socktype, proto, _canonname, sockaddr in results:
+            try:
+                address = ipaddress.ip_address(sockaddr[0])
+            except (ValueError, TypeError, IndexError):
+                raise OSError("Public artifact host resolved to an invalid address") from None
+            if not address.is_global:
+                raise OSError("Public artifact host resolved to a non-public address")
+            key = (str(address), result_family)
+            if key in seen:
+                continue
+            seen.add(key)
+            resolved.append({
+                "hostname": host,
+                "host": str(address),
+                "port": port,
+                "family": result_family,
+                "proto": proto,
+                "flags": 0,
+            })
+        if not resolved:
+            raise OSError("Public artifact host could not be resolved")
+        return resolved
+
+    async def close(self):
+        return None
+
+
+async def download_public_artifact(url: str, max_bytes: int = MAX_OUTPUT_IMAGE_BYTES) -> bytes:
+    """Download a signed public HTTPS artifact without provider credentials."""
+    if isinstance(max_bytes, bool) or not isinstance(max_bytes, int) or not 0 < max_bytes <= MAX_OUTPUT_IMAGE_BYTES:
+        raise ServerlessMediaError("Serverless image artifact exceeds the permitted size")
+    current_url = _validate_artifact_url(url)
+    resolver = _PublicResolver()
+    connector = aiohttp.TCPConnector(resolver=resolver, use_dns_cache=False, limit=4)
+    timeout = aiohttp.ClientTimeout(
+        total=_DOWNLOAD_TIMEOUT_SECONDS,
+        connect=10,
+        sock_read=15,
+    )
+    try:
+        async with aiohttp.ClientSession(
+            connector=connector,
+            timeout=timeout,
+            trust_env=False,
+            cookie_jar=aiohttp.DummyCookieJar(),
+        ) as session:
+            for redirect_count in range(MAX_REDIRECTS + 1):
+                _validate_artifact_url(current_url)
+                async with session.get(current_url, allow_redirects=False) as response:
+                    if response.status in {301, 302, 303, 307, 308}:
+                        location = response.headers.get("Location")
+                        if not location or redirect_count >= MAX_REDIRECTS:
+                            raise ServerlessMediaError("Serverless image artifact redirect is invalid")
+                        current_url = _validate_artifact_url(urljoin(current_url, location))
+                        continue
+                    if response.status != 200:
+                        raise ServerlessMediaError("Serverless image artifact download failed")
+                    payload = bytearray()
+                    async for chunk in response.content.iter_chunked(_CHUNK_SIZE):
+                        if not isinstance(chunk, bytes):
+                            raise ServerlessMediaError("Serverless image artifact response is invalid")
+                        if len(payload) + len(chunk) > max_bytes:
+                            raise ServerlessMediaError("Serverless image artifact exceeds the permitted size")
+                        payload.extend(chunk)
+                    if not payload:
+                        raise ServerlessMediaError("Serverless image artifact is empty")
+                    return bytes(payload)
+    except ServerlessMediaError:
+        raise
+    except Exception:
+        raise ServerlessMediaError("Serverless image artifact download failed") from None
+    raise ServerlessMediaError("Serverless image artifact download failed")
+
+
+def _validated_manifest(manifest):
+    if not isinstance(manifest, list) or len(manifest) > MAX_OUTPUT_FILES:
+        raise ServerlessMediaError("Serverless image manifest is invalid")
+    normalized = []
+    seen_prefixes = set()
+    prefixes = []
+    for item in manifest:
+        if not isinstance(item, dict):
+            raise ServerlessMediaError("Serverless image manifest is invalid")
+        if item.get("kind") != "image":
+            raise ServerlessMediaError("Only image collectors are supported by serverless media transport")
+        for key in ("collector_id", "job_id", "node_id"):
+            value = item.get(key)
+            if not isinstance(value, (str, int)) or isinstance(value, bool) or not str(value):
+                raise ServerlessMediaError("Serverless image manifest is invalid")
+        prefix = item.get("prefix")
+        if not isinstance(prefix, str) or not _PREFIX_RE.fullmatch(prefix) or prefix in {".", ".."}:
+            raise ServerlessMediaError("Serverless image manifest contains an unsafe filename prefix")
+        folded = prefix.casefold()
+        if folded in seen_prefixes:
+            raise ServerlessMediaError("Serverless image manifest prefixes must be unique")
+        seen_prefixes.add(folded)
+        prefixes.append(prefix)
+        normalized.append({
+            "collector_id": str(item["collector_id"]),
+            "job_id": str(item["job_id"]),
+            "node_id": str(item["node_id"]),
+            "prefix": prefix,
+        })
+    for first in prefixes:
+        for second in prefixes:
+            if first != second and second.casefold().startswith(first.casefold() + "_"):
+                raise ServerlessMediaError("Serverless image manifest prefixes are ambiguous")
+    return normalized
+
+
+def _artifact_filename_matches(filename, prefixes):
+    if not isinstance(filename, str):
+        return None
+    basename = filename.replace("\\", "/").rsplit("/", 1)[-1]
+    matches = [item for item in prefixes if basename.startswith(item["prefix"] + "_")]
+    if len(matches) > 1:
+        raise ServerlessMediaError("Serverless image artifact matches multiple collectors")
+    return matches[0] if matches else None
+
+
+def _canonical_artifact_identity(entry, filename):
+    artifact_path = entry.get("artifact_path")
+    artifact_type = entry.get("artifact_type", "output")
+    if artifact_path is not None:
+        if not isinstance(artifact_path, str) or not artifact_path or "\x00" in artifact_path:
+            raise ServerlessMediaError("Serverless image artifact identity is invalid")
+        normalized_path = os.path.normcase(os.path.normpath(artifact_path.replace("\\", "/")))
+    else:
+        subfolder = entry.get("subfolder", "")
+        if not isinstance(subfolder, str) or "\x00" in subfolder:
+            raise ServerlessMediaError("Serverless image artifact identity is invalid")
+        normalized_path = os.path.normcase(os.path.normpath(f"{subfolder}/{filename}"))
+    return str(artifact_type), normalized_path
+
+
+def _decode_base64_data(value, max_bytes=MAX_OUTPUT_IMAGE_BYTES):
+    if not isinstance(value, str) or not value:
+        raise ServerlessMediaError("Serverless image artifact data is invalid")
+    max_bytes = min(max_bytes, MAX_OUTPUT_IMAGE_BYTES)
+    max_encoded = ((max_bytes + 2) // 3) * 4
+    if len(value) > max_encoded:
+        raise ServerlessMediaError("Serverless image artifact exceeds the permitted size")
+    padding = len(value) - len(value.rstrip("="))
+    estimated_size = (len(value) // 4) * 3 - padding
+    if estimated_size > max_bytes:
+        raise ServerlessMediaError("Serverless image artifact exceeds the permitted size")
+    try:
+        payload = base64.b64decode(value, validate=True)
+    except (binascii.Error, ValueError):
+        raise ServerlessMediaError("Serverless image artifact data is invalid") from None
+    if not payload:
+        raise ServerlessMediaError("Serverless image artifact is empty")
+    if len(payload) > max_bytes:
+        raise ServerlessMediaError("Serverless image artifact exceeds the permitted size")
+    return payload
+
+
+def _decode_image_array(payload, total_array_bytes):
+    try:
+        with warnings.catch_warnings():
+            warnings.simplefilter("error", Image.DecompressionBombWarning)
+            image = Image.open(io.BytesIO(payload))
+            width, height = image.size
+            if width <= 0 or height <= 0 or width * height > MAX_IMAGE_PIXELS:
+                raise ServerlessMediaError("Serverless image dimensions exceed the permitted limit")
+            has_alpha = image.mode in {"RGBA", "LA"} or "transparency" in image.info
+            mode = "RGBA" if has_alpha else "RGB"
+            output_bytes = width * height * (4 if has_alpha else 3) * 4
+            if total_array_bytes + output_bytes > MAX_OUTPUT_ARRAY_BYTES:
+                raise ServerlessMediaError("Decoded serverless images exceed the permitted memory limit")
+            converted = image.convert(mode)
+            converted.load()
+            array = np.array(converted, dtype=np.float32, copy=True)
+            np.multiply(array, 1.0 / 255.0, out=array)
+            return array, output_bytes
+    except ServerlessMediaError:
+        raise
+    except (UnidentifiedImageError, OSError, ValueError, Image.DecompressionBombError, Image.DecompressionBombWarning):
+        raise ServerlessMediaError("Serverless image artifact could not be decoded") from None
+    except Exception:
+        raise ServerlessMediaError("Serverless image artifact could not be decoded") from None
+
+
+def _image_output(output):
+    """Unwrap handler output and reject explicit execution errors."""
+    if not isinstance(output, dict):
+        raise ServerlessMediaError("Serverless job output is invalid")
+    nested = output.get("output")
+    data = nested if isinstance(nested, dict) else output
+    for candidate in (output, data):
+        if candidate.get("error") or candidate.get("errors"):
+            raise ServerlessMediaError("Serverless job reported an execution error")
+
+    return data
+
+
+async def _select_image_payloads(data, expected, download):
+    """Match artifact identities and fetch bounded bytes, without image decoding."""
+    artifacts = data.get("images", [])
+    if not isinstance(artifacts, list) or len(artifacts) > MAX_OUTPUT_FILES:
+        raise ServerlessMediaError("Serverless job returned too many image files")
+
+    selected = {item["prefix"]: [] for item in expected}
+    identities = set()
+    total_payload_bytes = 0
+    for entry in artifacts:
+        if not isinstance(entry, dict):
+            continue
+        filename = entry.get("filename")
+        manifest_entry = _artifact_filename_matches(filename, expected)
+        if manifest_entry is None:
+            continue
+        normalized_filename = filename.replace("\\", "/")
+        if "/" in normalized_filename or not _SAFE_FILENAME_RE.fullmatch(filename):
+            raise ServerlessMediaError("Serverless image artifact filename is invalid")
+        if Path(filename).suffix.lower() not in _IMAGE_EXTENSIONS:
+            raise ServerlessMediaError("Serverless image artifact has an unsupported file type")
+        if "artifact_type" in entry and entry["artifact_type"] != "output":
+            raise ServerlessMediaError("Expected serverless image artifact was not an output image")
+        identity = _canonical_artifact_identity(entry, filename)
+        if identity in identities:
+            raise ServerlessMediaError("Duplicate serverless image artifact identity")
+        identities.add(identity)
+        match = re.match(rf"^{re.escape(manifest_entry['prefix'])}_(\d+)(?:_|\.)", filename)
+        if match is None:
+            raise ServerlessMediaError("Expected serverless image filename counter is invalid")
+        artifact_type = entry.get("type")
+        remaining_bytes = MAX_OUTPUT_TOTAL_BYTES - total_payload_bytes
+        if remaining_bytes <= 0:
+            raise ServerlessMediaError("Serverless image artifacts exceed the permitted total size")
+        if artifact_type == "base64":
+            payload = _decode_base64_data(entry.get("data"), remaining_bytes)
+        elif artifact_type in {"gcs_url", "s3_url", "url"}:
+            url = entry.get("data") or entry.get("url")
+            url = _validate_artifact_url(url)
+            try:
+                if download is None:
+                    payload = await download_public_artifact(
+                        url, max_bytes=min(MAX_OUTPUT_IMAGE_BYTES, remaining_bytes)
+                    )
+                else:
+                    payload = await download(url)
+            except ServerlessMediaError:
+                raise
+            except Exception:
+                raise ServerlessMediaError("Serverless image artifact download failed") from None
+            if not isinstance(payload, bytes) or not payload:
+                raise ServerlessMediaError("Serverless image artifact response is invalid")
+            if len(payload) > MAX_OUTPUT_IMAGE_BYTES:
+                raise ServerlessMediaError("Serverless image artifact exceeds the permitted size")
+        else:
+            raise ServerlessMediaError("Serverless image artifact transport type is unsupported")
+        total_payload_bytes += len(payload)
+        if total_payload_bytes > MAX_OUTPUT_TOTAL_BYTES:
+            raise ServerlessMediaError("Serverless image artifacts exceed the permitted total size")
+        selected[manifest_entry["prefix"]].append((int(match.group(1)), filename, identity, payload))
+
+    if any(not selected[item["prefix"]] for item in expected):
+        raise ServerlessMediaError("Serverless job is missing an expected collector image")
+    return selected
+
+
+def _decode_image_groups(selected, expected):
+    """Decode in stable counter order, bounding array memory across collectors."""
+    result = {}
+    total_array_bytes = 0
+    for manifest_entry in expected:
+        prefix = manifest_entry["prefix"]
+        rows = sorted(selected[prefix], key=lambda row: (row[0], row[1], row[2]))
+        arrays = []
+        shape = None
+        for _counter, _filename, _identity, payload in rows:
+            array, added_bytes = _decode_image_array(payload, total_array_bytes)
+            total_array_bytes += added_bytes
+            if shape is None:
+                shape = array.shape
+            elif array.shape != shape:
+                raise ServerlessMediaError("Images from one serverless collector have inconsistent dimensions")
+            arrays.append(array)
+        result.setdefault(manifest_entry["job_id"], []).extend(arrays)
+    return result
+
+
+async def collect_images(output: dict, manifest: list, download=None) -> dict[str, list[np.ndarray]]:
+    """Validate and decode expected image artifacts, grouped by serverless job ID."""
+    data = _image_output(output)
+    expected = _validated_manifest(manifest)
+    if not expected:
+        return {}
+    selected = await _select_image_payloads(data, expected, download)
+    return _decode_image_groups(selected, expected)

api/orchestration/serverless_prompt.py

@@ -0,0 +1,420 @@
+"""Compile prepared distributed prompts into worker-side ComfyUI image jobs.
+
+This module is deliberately pure: it only copies and rewrites an API prompt
+mapping and never imports or executes ComfyUI nodes.
+"""
+
+from __future__ import annotations
+
+import copy
+import hashlib
+import json
+import re
+
+
+_SUPPORTED_DISTRIBUTED = {
+    "DistributedCollector",
+    "DistributedSeed",
+    "DistributedValue",
+    "DistributedModelName",
+}
+_REMOVED_SCALAR_NODES = {
+    "DistributedSeed",
+    "DistributedValue",
+    "DistributedModelName",
+}
+_PRIMITIVE_NODES = {
+    "PrimitiveBoolean": False,
+    "PrimitiveFloat": 0.0,
+    "PrimitiveInt": 0,
+    "PrimitiveString": "",
+}
+_REMOVED_NODE_OUTPUTS = {
+    "DistributedCollector": {0, 1},
+    "DistributedSeed": {0},
+    "DistributedValue": {0},
+    "DistributedModelName": {0},
+}
+_SEED_DEFAULT = 1125899906842
+
+
+def _is_link(value):
+    return isinstance(value, list) and len(value) == 2
+
+
+def _is_unsupported_distributed(class_type):
+    if not isinstance(class_type, str) or class_type in _SUPPORTED_DISTRIBUTED:
+        return False
+    lowered = class_type.lower()
+    return "distributed" in lowered or "batchdivider" in lowered
+
+
+def _safe_component(value):
+    cleaned = re.sub(r"[^A-Za-z0-9_-]+", "_", str(value)).strip("_-")
+    return cleaned[:24] or "empty"
+
+
+def _filename_prefix(job_id, worker_id, collector_id, kind):
+    identity = json.dumps(
+        [job_id, worker_id, collector_id, kind],
+        ensure_ascii=False,
+        separators=(",", ":"),
+    )
+    digest = hashlib.sha256(identity.encode("utf-8")).hexdigest()
+    parts = (
+        "serverless",
+        _safe_component(job_id),
+        _safe_component(worker_id),
+        _safe_component(collector_id),
+        kind,
+        digest,
+    )
+    return "_".join(parts)
+
+
+def _worker_index(worker_id):
+    """Mirror nodes.utilities worker-index parsing; None means fallback."""
+    try:
+        if worker_id.startswith("worker_"):
+            return int(worker_id.split("_")[1])
+        return int(worker_id)
+    except (ValueError, IndexError):
+        return None
+
+
+def _coerce(value, value_type):
+    if value_type == "INT":
+        return int(float(value))
+    if value_type == "FLOAT":
+        return float(value)
+    return value
+
+
+def _coerce_safe(value, value_type):
+    try:
+        return _coerce(value, value_type)
+    except (TypeError, ValueError):
+        return value
+
+
+def _stringify_model_name(value):
+    if isinstance(value, str):
+        return value
+    if isinstance(value, (int, float, bool)):
+        return str(value)
+    try:
+        return json.dumps(value, indent=4)
+    except (TypeError, ValueError):
+        return str(value)
+
+
+def _model_name_result(text):
+    if isinstance(text, list):
+        values = [_stringify_model_name(value) for value in text]
+        return values[0] if len(values) == 1 else values
+    return _stringify_model_name(text)
+
+
+def _validate_prepared_prompt(prepared_prompt):
+    """Validate graph shape, links, collectors, and supported topology."""
+    if not isinstance(prepared_prompt, dict):
+        raise ValueError("prepared prompt must be an API graph mapping")
+
+    source_nodes = {}
+    for raw_id, node in prepared_prompt.items():
+        node_id = str(raw_id)
+        if node_id in source_nodes:
+            raise ValueError("prompt has duplicate node IDs after string normalization")
+        if not isinstance(node, dict):
+            raise ValueError(f"prompt node {node_id!r} must be an object")
+        class_type = node.get("class_type")
+        if not isinstance(class_type, str):
+            raise ValueError(f"prompt node {node_id!r} is missing a class_type")
+        if _is_unsupported_distributed(class_type):
+            raise ValueError(f"unsupported distributed or batch node: {class_type}")
+        inputs = node.get("inputs", {})
+        if not isinstance(inputs, dict):
+            raise ValueError(f"prompt node {node_id!r} inputs must be an object")
+        source_nodes[node_id] = node
+
+    if not source_nodes:
+        raise ValueError("prepared prompt contains no nodes")
+
+    # Validate every API link before any graph rewriting. Slots on the nodes
+    # removed by this compiler have a known schema and are checked exactly.
+    for node_id, node in source_nodes.items():
+        for input_name, value in node.get("inputs", {}).items():
+            if not _is_link(value):
+                continue
+            upstream_id, output_slot = value
+            upstream_id = str(upstream_id)
+            if upstream_id not in source_nodes:
+                raise ValueError(
+                    f"invalid link at node {node_id!r} input {input_name!r}: "
+                    f"source {upstream_id!r} does not exist"
+                )
+            if isinstance(output_slot, bool) or not isinstance(output_slot, int) or output_slot < 0:
+                raise ValueError(
+                    f"invalid link at node {node_id!r} input {input_name!r}: "
+                    "output slot must be a nonnegative integer"
+                )
+            upstream_class = source_nodes[upstream_id]["class_type"]
+            valid_slots = _REMOVED_NODE_OUTPUTS.get(upstream_class)
+            if valid_slots is not None and output_slot not in valid_slots:
+                raise ValueError(
+                    f"invalid output slot {output_slot} for removed node "
+                    f"{upstream_class} {upstream_id!r}"
+                )
+
+    collector_ids = sorted(
+        (node_id for node_id, node in source_nodes.items() if node["class_type"] == "DistributedCollector"),
+        key=str,
+    )
+    if not collector_ids:
+        raise ValueError("prepared prompt contains no DistributedCollector nodes")
+
+    # Only image collectors are supported by the current generic handler.
+    for collector_id in collector_ids:
+        inputs = source_nodes[collector_id].get("inputs", {})
+        if "audio" in inputs:
+            raise ValueError("collector audio input is unsupported by this image-only compiler")
+        if not _is_link(inputs.get("images")):
+            raise ValueError(f"collector {collector_id!r} is missing a linked image input")
+        source_id = str(inputs["images"][0])
+        source_class = source_nodes[source_id]["class_type"]
+        if source_class in _REMOVED_SCALAR_NODES:
+            raise ValueError(f"collector {collector_id!r} image input must link to an image node")
+
+    # A collector cannot be used, directly or through processing, as another
+    # collector's input: this first compiler handles disconnected jobs only.
+    for collector_id in collector_ids:
+        pending = [str(source_nodes[collector_id]["inputs"]["images"][0])]
+        seen = set()
+        while pending:
+            node_id = pending.pop()
+            if node_id in seen:
+                continue
+            seen.add(node_id)
+            if source_nodes[node_id]["class_type"] == "DistributedCollector":
+                raise ValueError("collector-to-collector dependence is unsupported")
+            for value in source_nodes[node_id].get("inputs", {}).values():
+                if _is_link(value):
+                    pending.append(str(value[0]))
+
+    return source_nodes, collector_ids
+
+
+def _make_scalar_resolver(source_nodes):
+    """Build pure resolvers for distributed scalar nodes and stock primitives."""
+    # Resolve only stock primitive nodes. A visited set makes malformed
+    # primitive-to-primitive cycles fail clearly instead of recursing forever.
+    def resolve_primitive(node_id, visiting=None):
+        node_id = str(node_id)
+        node = source_nodes[node_id]
+        class_type = node["class_type"]
+        if class_type not in _PRIMITIVE_NODES:
+            raise ValueError("linked value must be literal or supported PrimitiveInt/Float/String/Boolean")
+        if visiting is None:
+            visiting = set()
+        if node_id in visiting:
+            raise ValueError(f"cycle while resolving primitive value at node {node_id!r}")
+        visiting.add(node_id)
+        value = node.get("inputs", {}).get("value", _PRIMITIVE_NODES[class_type])
+        if _is_link(value):
+            parent_id, output_slot = str(value[0]), value[1]
+            if output_slot != 0:
+                raise ValueError(f"invalid output slot {output_slot} for primitive node {parent_id!r}")
+            if source_nodes[parent_id]["class_type"] not in _PRIMITIVE_NODES:
+                raise ValueError("linked primitive value must come from a stock Primitive node")
+            result = resolve_primitive(parent_id, visiting)
+        else:
+            result = copy.deepcopy(value)
+        visiting.remove(node_id)
+        return result
+
+    def resolve_literal_or_primitive(value, context):
+        if _is_link(value):
+            source_id, output_slot = str(value[0]), value[1]
+            if output_slot != 0 or source_nodes[source_id]["class_type"] not in _PRIMITIVE_NODES:
+                raise ValueError(f"{context} must be a literal or supported Primitive link")
+            try:
+                return resolve_primitive(source_id)
+            except ValueError as exc:
+                if "cycle" in str(exc):
+                    raise
+                raise ValueError(f"{context} must be a literal or supported Primitive link") from None
+        return copy.deepcopy(value)
+
+    def resolve_hidden(node_id, name, default):
+        value = source_nodes[node_id].get("inputs", {}).get(name, default)
+        if _is_link(value):
+            raise ValueError(f"{name} on distributed node {node_id!r} must be a literal")
+        return copy.deepcopy(value)
+
+    resolved_distributed = {}
+
+    def resolve_distributed(node_id, output_slot):
+        node_id = str(node_id)
+        class_type = source_nodes[node_id]["class_type"]
+        if output_slot != 0:
+            raise ValueError(f"invalid output slot {output_slot} for {class_type} {node_id!r}")
+        cache_key = (node_id, output_slot)
+        if cache_key in resolved_distributed:
+            return copy.deepcopy(resolved_distributed[cache_key])
+        inputs = source_nodes[node_id].get("inputs", {})
+        if class_type == "DistributedSeed":
+            seed = resolve_literal_or_primitive(inputs.get("seed", _SEED_DEFAULT), f"seed on {node_id!r}")
+            is_worker = resolve_hidden(node_id, "is_worker", False)
+            worker_id = resolve_hidden(node_id, "worker_id", "")
+            if is_worker:
+                worker_index = _worker_index(worker_id)
+                if worker_index is not None:
+                    seed = seed + worker_index + 1
+            result = seed
+        elif class_type == "DistributedValue":
+            default_value = resolve_literal_or_primitive(
+                inputs.get("default_value", ""), f"default_value on {node_id!r}"
+            )
+            worker_values = resolve_literal_or_primitive(
+                inputs.get("worker_values", "{}"), f"worker_values on {node_id!r}"
+            )
+            is_worker = resolve_hidden(node_id, "is_worker", False)
+            worker_id = resolve_hidden(node_id, "worker_id", "")
+            try:
+                values = json.loads(worker_values) if isinstance(worker_values, str) else worker_values
+            except json.JSONDecodeError:
+                values = {}
+            if not isinstance(values, dict):
+                values = {}
+            value_type = values.get("_type", "STRING")
+            fallback = _coerce_safe(default_value, value_type)
+            result = fallback
+            if is_worker:
+                worker_index = _worker_index(worker_id)
+                if worker_index is not None:
+                    raw_value = values.get(str(worker_index + 1), "")
+                    if raw_value:
+                        try:
+                            result = _coerce(raw_value, value_type)
+                        except (ValueError, IndexError):
+                            result = fallback
+        elif class_type == "DistributedModelName":
+            text = resolve_literal_or_primitive(
+                inputs.get("text", ""), f"DistributedModelName text on {node_id!r}"
+            )
+            result = _model_name_result(text)
+        else:
+            raise ValueError(f"unsupported distributed node: {class_type}")
+        resolved_distributed[cache_key] = copy.deepcopy(result)
+        return result
+
+    return resolve_distributed
+
+
+def _build_savers(source_nodes, collector_ids):
+    """Construct stable SaveImage nodes and their collector metadata."""
+    # The prepared collector values define the artifact identity. The fallback
+    # for absent hidden values is stable and retains the collector's job scope.
+    collector_specs = []
+    max_numeric_id = 0
+    for node_id in source_nodes:
+        try:
+            max_numeric_id = max(max_numeric_id, int(node_id))
+        except ValueError:
+            pass
+    next_numeric_id = max_numeric_id + 1
+    for collector_id in collector_ids:
+        inputs = source_nodes[collector_id].get("inputs", {})
+        raw_job_id = inputs.get("multi_job_id", collector_id)
+        if _is_link(raw_job_id):
+            raise ValueError(f"collector {collector_id!r} multi_job_id must be a literal")
+        job_id = str(collector_id if raw_job_id in (None, "") else raw_job_id)
+        raw_worker_id = inputs.get("worker_id", "")
+        if _is_link(raw_worker_id):
+            raise ValueError(f"collector {collector_id!r} worker_id must be a literal")
+        worker_id = "" if raw_worker_id is None else str(raw_worker_id)
+        saver_id = str(next_numeric_id)
+        next_numeric_id += 1
+        prefix = _filename_prefix(job_id, worker_id, collector_id, "image")
+        collector_specs.append(
+            {
+                "collector_id": collector_id,
+                "job_id": job_id,
+                "node_id": saver_id,
+                "kind": "image",
+                "prefix": prefix,
+                "source_link": copy.deepcopy(inputs["images"]),
+            }
+        )
+
+    saver_nodes = {}
+    for spec in collector_specs:
+        saver_nodes[spec["node_id"]] = {
+            "class_type": "SaveImage",
+            "inputs": {
+                "images": spec["source_link"],
+                "filename_prefix": spec["prefix"],
+            },
+            "_meta": {"title": f"Serverless output: collector {spec['collector_id']} (image)"},
+        }
+
+    return collector_specs, saver_nodes
+
+
+def _prune_graph(source_nodes, collector_specs, saver_nodes, resolve_distributed):
+    """Keep saver ancestors, replacing distributed scalar links with literals."""
+    all_nodes = {node_id: copy.deepcopy(node) for node_id, node in source_nodes.items()}
+    all_nodes.update(copy.deepcopy(saver_nodes))
+    needed = set()
+    pending = [spec["node_id"] for spec in collector_specs]
+    while pending:
+        node_id = pending.pop()
+        if node_id in needed:
+            continue
+        needed.add(node_id)
+        node = all_nodes[node_id]
+        if node["class_type"] == "DistributedCollector":
+            raise ValueError("collector-to-collector dependence is unsupported")
+        for input_name, value in list(node.get("inputs", {}).items()):
+            if not _is_link(value):
+                continue
+            upstream_id, output_slot = str(value[0]), value[1]
+            upstream_class = source_nodes[upstream_id]["class_type"]
+            if upstream_class in _REMOVED_SCALAR_NODES:
+                node["inputs"][input_name] = resolve_distributed(upstream_id, output_slot)
+            else:
+                pending.append(upstream_id)
+
+    compiled = {
+        node_id: copy.deepcopy(node)
+        for node_id, node in all_nodes.items()
+        if node_id in needed
+    }
+    if any("distributed" in node["class_type"].lower() for node in compiled.values()):
+        raise ValueError("compiled prompt still contains a distributed dependency")
+
+    return compiled
+
+
+def compile_serverless_prompt(prepared_prompt: dict) -> tuple[dict, list[dict]]:
+    """Compile a prepared worker prompt to an image-only serverless graph.
+
+    Every DistributedCollector's original ``images`` input is connected to a
+    new SaveImage node. Only those savers and their upstream dependencies are
+    retained. DistributedSeed/Value/ModelName links are resolved as scalar
+    literals; unsupported node execution is never attempted.
+    """
+    source_nodes, collector_ids = _validate_prepared_prompt(prepared_prompt)
+    resolve_distributed = _make_scalar_resolver(source_nodes)
+    collector_specs, saver_nodes = _build_savers(source_nodes, collector_ids)
+    compiled = _prune_graph(
+        source_nodes,
+        collector_specs,
+        saver_nodes,
+        resolve_distributed,
+    )
+    manifest = [
+        {key: spec[key] for key in ("collector_id", "job_id", "node_id", "kind", "prefix")}
+        for spec in collector_specs
+    ]
+    return compiled, manifest

api/orchestration/serverless_runtime.py

@@ -0,0 +1,380 @@
+"""Master-owned asynchronous Runpod jobs, independent of worker callbacks."""
+import asyncio
+import time
+import uuid
+from pathlib import Path
+
+from .runpod_client import RunpodClient, RunpodError, AmbiguousSubmission
+from .serverless_ledger import JobLedger
+from .serverless_state import (
+    PROVIDER_STATES, PROVIDER_TERMINAL, belongs_to_pool, is_unresolved,
+    occupies_capacity, terminal_provider_status,
+)
+
+
+# Fixed per-worker cap on this master's outstanding Runpod jobs; equals the
+# Images per run maximum (MAX_JOBS_PER_RUN in utils/serverless_config.py), so
+# every image of a run is submitted at once. Deliberately not configurable or
+# derived from jobs_per_run: unresolved jobs from earlier runs (ambiguous
+# submissions, unconfirmed cancels) still count against it, and a constant
+# never has to change while such jobs exist.
+PER_WORKER_JOB_LIMIT = 16
+
+
+async def decode_results(output, manifest):
+    from .serverless_media import collect_images
+    import torch
+    images = await collect_images(output, manifest)
+    return {job_id: [torch.from_numpy(image).unsqueeze(0) for image in batch] for job_id, batch in images.items()}
+
+
+def state_directory():
+    import folder_paths
+    return Path(folder_paths.get_user_directory()) / "distributed" / "serverless"
+
+
+def get_secret_store():
+    from ...utils.serverless_config import SecretStore
+    return SecretStore(state_directory() / "credentials.json")
+
+
+def get_manager():
+    import server
+    from ...utils.network import get_client_session
+    ps = server.PromptServer.instance
+    manager = getattr(ps, "distributed_serverless", None)
+    if manager is None:
+        manager = ServerlessManager(ps, get_secret_store(), state_directory() / "jobs.json", get_client_session)
+        ps.distributed_serverless = manager
+    return manager
+
+
+class ServerlessManager:
+    def __init__(self, prompt_server, secrets, ledger_path, session_factory):
+        self.server = prompt_server
+        self.secrets = secrets
+        self.ledger = JobLedger(ledger_path)
+        self.session_factory = session_factory
+        self.tasks = {}
+        self.runs = {}
+        self.pool_limits = {}
+        self.health_cache = {}
+        self.health_locks = {}
+        self.poll_seconds = 2.0
+        self.capacity_changed = asyncio.Condition()
+        self.recovery_lock = asyncio.Lock()
+        self._recover_local_records()
+
+    def _recover_local_records(self):
+        # WAITING is committed before admission; it cannot have reached Runpod.
+        # SUBMITTING is an intent record, so a lost ID must remain reserved.
+        for record in self.ledger.all():
+            if record.get("status") == "WAITING" and not record.get("job_id"):
+                self.ledger.update(record["record_id"], status="CANCELLED", updated_at=time.time())
+            elif record.get("status") == "SUBMITTING" and not record.get("job_id"):
+                self.ledger.update(record["record_id"], status="UNKNOWN", updated_at=time.time())
+
+    def _task_is_active(self, record_id):
+        task = self.tasks.get(record_id)
+        return task is not None and not task.done()
+
+    def pool_is_active(self, worker_id):
+        """Protect both live local work and unresolved pre-restart provider work."""
+        for rid, run in self.runs.items():
+            pool_id = run["worker"].get("pool_id", run["worker"]["id"])
+            if str(pool_id) == str(worker_id) and self._task_is_active(rid):
+                return True
+        return any(belongs_to_pool(record, worker_id) and is_unresolved(record)
+                   for record in self.ledger.all())
+
+    async def _reserve_provider_capacity(self, run):
+        pool_id = run["worker"].get("pool_id", run["worker"]["id"])
+        async with self.capacity_changed:
+            while True:
+                self._check_master(run)
+                outstanding = sum(belongs_to_pool(record, pool_id) and occupies_capacity(record)
+                                  for record in self.ledger.all())
+                if outstanding < PER_WORKER_JOB_LIMIT:
+                    # Claim atomically before any await that could submit a billed job.
+                    self.ledger.update(run["record_id"], status="SUBMITTING", updated_at=time.time())
+                    return
+                await self.capacity_changed.wait()
+
+    async def _notify_capacity(self):
+        async with self.capacity_changed:
+            self.capacity_changed.notify_all()
+
+    async def _client(self, worker):
+        pool_id = worker.get("pool_id", worker["id"])
+        key = self.secrets.get(pool_id)
+        return RunpodClient(await self.session_factory(), worker["endpoint_id"], key)
+
+    async def health(self, worker, *, fresh=False):
+        pool_id = worker.get("pool_id", worker["id"])
+        cache_key = (pool_id, worker["endpoint_id"])
+        lock = self.health_locks.setdefault(cache_key, asyncio.Lock())
+        async with lock:
+            cached = self.health_cache.get(cache_key)
+            if cached and not fresh and time.monotonic() - cached[0] < 10:
+                return cached[1]
+            client = await self._client(worker)
+            data = await client.health()
+            jobs = data.get("jobs", {})
+            if not isinstance(jobs, dict) or not isinstance(data.get("workers"), dict):
+                raise RunpodError("Runpod returned an invalid endpoint health record")
+            try:
+                pending = max(0, int(jobs.get("inQueue", 0))) + max(0, int(jobs.get("inProgress", 0)))
+            except (ValueError, TypeError):
+                raise RunpodError("Runpod returned invalid queue counts") from None
+            result = {"ok": True, "queueRemaining": pending, "message": "Queued / processing" if pending else "Ready (scales from zero)"}
+            self.health_cache[cache_key] = (time.monotonic(), result)
+            return result
+
+    def _semaphore(self, worker):
+        # The limit is a constant, so it never has to be swapped while this
+        # worker still has unresolved jobs.
+        pool_id = worker.get("pool_id", worker["id"])
+        semaphore = self.pool_limits.get(pool_id)
+        if semaphore is None:
+            semaphore = asyncio.Semaphore(PER_WORKER_JOB_LIMIT)
+            self.pool_limits[pool_id] = semaphore
+        return semaphore
+
+    def ensure_capacity(self, count):
+        if sum(not task.done() for task in self.tasks.values()) + count > 64:
+            raise ValueError("Distributed already has too many pending serverless jobs (limit 64)")
+
+    async def start(self, execution_id, prompt_id, prepared_jobs):
+        self.ensure_capacity(len(prepared_jobs))
+        new_runs = []
+        # Journal every local slot before starting any billed submission.
+        for prepared in prepared_jobs:
+            worker = prepared["worker"]
+            semaphore = self._semaphore(worker)
+            record_id = uuid.uuid4().hex
+            now = time.time()
+            self.ledger.update(record_id, execution_id=execution_id, prompt_id=prompt_id,
+                               worker_id=worker.get("pool_id", worker["id"]), participant_id=worker["id"],
+                               endpoint_id=worker["endpoint_id"], job_id=None, status="WAITING", created_at=now, updated_at=now)
+            run = dict(prepared, execution_id=execution_id, prompt_id=prompt_id, record_id=record_id,
+                       provider_job_id=None, client=None, deadline=time.monotonic() + worker["timeout_seconds"])
+            self.runs[record_id] = run
+            new_runs.append((record_id, run, semaphore))
+        for record_id, run, semaphore in new_runs:
+            self.tasks[record_id] = asyncio.create_task(self._run(run, semaphore), name=f"distributed-serverless-{record_id}")
+        # Bound in-memory completed tracking as well as the on-disk journal.
+        done = [rid for rid, task in self.tasks.items() if task.done()]
+        for rid in done[:-200]:
+            self.tasks.pop(rid, None)
+            self.runs.pop(rid, None)
+
+    def is_pending(self, collector_job_id, participant_id):
+        return any(not task.done() and run["worker"]["id"] == participant_id and
+                   any(m["job_id"] == collector_job_id for m in run["manifest"])
+                   for rid, task in self.tasks.items() for run in [self.runs[rid]])
+
+    def owns(self, collector_job_id, participant_id):
+        return any(run["worker"]["id"] == participant_id and
+                   any(m["job_id"] == collector_job_id for m in run["manifest"]) for run in self.runs.values())
+
+    async def _deliver(self, run, images=None, error=None):
+        async with self.server.distributed_jobs_lock:
+            for binding in run["manifest"]:
+                queue = self.server.distributed_pending_jobs.get(binding["job_id"])
+                if queue is None:
+                    continue  # A cancelled/finished collector must never be resurrected.
+                if error:
+                    queue.put_nowait({"worker_id": run["worker"]["id"], "serverless_error": error, "is_last": True})
+                else:
+                    batch = images[binding["job_id"]]
+                    for index, tensor in enumerate(batch):
+                        queue.put_nowait({"worker_id": run["worker"]["id"], "image_index": index,
+                                          "tensor": tensor, "is_last": index == len(batch) - 1})
+
+    async def _cancel_provider(self, run):
+        if run["provider_job_id"] and run["client"]:
+            try:
+                result = await run["client"].cancel(run["provider_job_id"])
+                return terminal_provider_status(result)
+            except Exception:
+                return None
+        return None
+
+    def _check_master(self, run):
+        queue = getattr(self.server, "prompt_queue", None)
+        if queue is None:
+            return
+        history = queue.get_history(run["prompt_id"])
+        record = history.get(run["prompt_id"], {})
+        if record.get("status", {}).get("status_str") == "error":
+            raise RunpodError("Master workflow failed; serverless work stopped")
+        if not record and hasattr(queue, "get_current_queue"):
+            running, pending = queue.get_current_queue()
+            if not any(str(item[1]) == run["prompt_id"] for item in [*running, *pending]):
+                raise RunpodError("Master workflow was removed from the queue; serverless work stopped")
+
+    async def _run(self, run, semaphore):
+        rid = run["record_id"]
+        submitted = False
+        provider_terminal = False
+        try:
+            async with asyncio.timeout(max(0, run["deadline"] - time.monotonic())):
+                async with semaphore:
+                    await self._reserve_provider_capacity(run)
+                    client = await self._client(run["worker"])
+                    run["client"] = client
+                    submitted = True
+                    job_id = await client.submit(run["workflow"], run["images"], run["worker"]["timeout_seconds"])
+                    run["provider_job_id"] = job_id
+                    # Persist immediately: all subsequent actions use this exact ID.
+                    self.ledger.update(rid, job_id=job_id, status="IN_QUEUE", updated_at=time.time())
+                    while True:
+                        self._check_master(run)
+                        response = await client.status(job_id)
+                        status = response.get("status")
+                        if not isinstance(status, str) or status not in PROVIDER_STATES:
+                            raise RunpodError("Runpod returned an unknown job state")
+                        provider_terminal = status in PROVIDER_TERMINAL
+                        if status == "COMPLETED":
+                            output = response.get("output")
+                            if not isinstance(output, dict) or output.get("error") or output.get("errors"):
+                                raise RunpodError("Serverless workflow reported an output error; inspect the provider job")
+                            self.ledger.update(rid, status="DOWNLOADING", updated_at=time.time())
+                            images = await decode_results(output, run["manifest"])
+                            await self._deliver(run, images=images)
+                            self.ledger.update(rid, status="COMPLETED", updated_at=time.time())
+                            return
+                        self.ledger.update(rid, status=status, updated_at=time.time())
+                        if provider_terminal:
+                            raise RunpodError(f"Serverless job ended with {status}")
+                        await asyncio.sleep(self.poll_seconds)
+        except AmbiguousSubmission as exc:
+            self.ledger.update(rid, status="UNKNOWN", error=str(exc), updated_at=time.time())
+            await self._deliver(run, error=str(exc))
+        except (asyncio.TimeoutError, asyncio.CancelledError) as exc:
+            terminal = "FAILED" if provider_terminal else await self._cancel_provider(run)
+            if submitted and not run["provider_job_id"]:
+                status = "UNKNOWN"
+                error = "Submission interrupted before its job ID was received; check Runpod before retrying"
+            elif isinstance(exc, asyncio.TimeoutError):
+                status = terminal or ("CANCEL_REQUESTED" if run["provider_job_id"] else "TIMED_OUT")
+                error = "Serverless job exceeded its queue/execution deadline"
+            else:
+                status = terminal or ("CANCEL_REQUESTED" if run["provider_job_id"] else "CANCELLED")
+                error = "Serverless work stopped" if terminal or not submitted else "Serverless cancellation requested; provider confirmation is pending"
+            self.ledger.update(rid, status=status, error=error, updated_at=time.time())
+            await self._deliver(run, error=error)
+        except Exception as exc:
+            # If polling/decoding failed, stop only our own provider job, never the pool.
+            terminal = "FAILED" if provider_terminal else await self._cancel_provider(run)
+            error = str(exc) if isinstance(exc, RunpodError) else "Serverless processing failed; check the workflow and endpoint contract"
+            status = terminal or ("CANCEL_REQUESTED" if run["provider_job_id"] else "FAILED")
+            self.ledger.update(rid, status=status, error=error, updated_at=time.time())
+            await self._deliver(run, error=error)
+        finally:
+            # Completed tracking retains IDs/bindings only, not potentially large
+            # base64 inputs, workflow metadata, or a client holding credentials.
+            run.pop("workflow", None)
+            run.pop("images", None)
+            run["client"] = None
+            # A released local semaphore alone cannot release a durable reservation.
+            await self._notify_capacity()
+
+    async def wait_for_execution(self, execution_id):
+        tasks = [task for rid, task in self.tasks.items() if self.runs[rid]["execution_id"] == execution_id]
+        await asyncio.gather(*tasks, return_exceptions=False)
+
+    def _detached_records(self, worker_id=None, execution_id=None):
+        return [record for record in self.ledger.all()
+                if is_unresolved(record) and not self._task_is_active(record["record_id"])
+                and (worker_id is None or belongs_to_pool(record, worker_id))
+                and (execution_id is None or record.get("execution_id") == execution_id)]
+
+    async def _recover_provider_record(self, record, *, cancel=False):
+        """Reconcile an exact saved ID, never submit or resume a workflow."""
+        if not record.get("job_id"):
+            return False
+        status = None
+        try:
+            client = await self._client({"id": record["worker_id"], "endpoint_id": record["endpoint_id"]})
+            response = await (client.cancel(record["job_id"]) if cancel else client.status(record["job_id"]))
+            status = terminal_provider_status(response)
+        except Exception:
+            pass  # Unreachable/expired is not proof of provider termination.
+        if status is not None or cancel:
+            self.ledger.update(record["record_id"], status=status or "CANCEL_REQUESTED", updated_at=time.time())
+        return status is not None
+
+    async def reconcile(self, worker_id=None):
+        """Read terminal states for detached jobs and release only proven capacity."""
+        resolved = 0
+        async with self.recovery_lock:
+            for record in self._detached_records(worker_id):
+                resolved += await self._recover_provider_record(record)
+        await self._notify_capacity()
+        return resolved
+
+    async def acknowledge_recovery(self, worker_id, record_id, *, provider_checked=False):
+        """Explicit operator escape hatch for lost IDs/expired provider records.
+
+        This records a human's verification, not a cancellation or provider
+        status. It is never called automatically or allowed for live tasks.
+        """
+        if provider_checked is not True:
+            raise ValueError("Check Runpod and confirm that this job is no longer running before resolving it")
+        async with self.recovery_lock:
+            record = next((r for r in self._detached_records(worker_id) if r["record_id"] == record_id), None)
+            if record is None:
+                raise ValueError("Unresolved inactive job not found for this worker")
+            self.ledger.update(record_id, status="RESOLVED", updated_at=time.time(),
+                               error="Recovery explicitly acknowledged after operator checked Runpod; not provider-confirmed")
+        await self._notify_capacity()
+
+    async def cancel(self, worker_id=None, execution_id=None, collector_job_id=None):
+        targets = {}
+        for rid, task in self.tasks.items():
+            run = self.runs[rid]
+            if worker_id and run["worker"].get("pool_id", run["worker"]["id"]) != worker_id:
+                continue
+            if execution_id and run["execution_id"] != execution_id:
+                continue
+            if collector_job_id and not any(m["job_id"] == collector_job_id for m in run["manifest"]):
+                continue
+            if not task.done():
+                # Repeated requests must not interrupt the first cancellation's cleanup.
+                if not task.cancelling():
+                    task.cancel()
+                targets[rid] = task
+        if targets:
+            await asyncio.gather(*targets.values(), return_exceptions=True)
+        recovered = 0
+        async with self.recovery_lock:
+            for record in self._detached_records(worker_id, execution_id):
+                rid = record["record_id"]
+                # A task cancelled before its first step never enters _run's handlers.
+                # A failed start() may also leave a journalled but unstarted local slot.
+                if record.get("status") == "WAITING" and not record.get("job_id"):
+                    run = self.runs.get(rid)
+                    if run is not None and (collector_job_id is None or any(m["job_id"] == collector_job_id for m in run["manifest"])):
+                        self.ledger.update(rid, status="CANCELLED", updated_at=time.time())
+                        run.pop("workflow", None)
+                        run.pop("images", None)
+                        await self._deliver(run, error="Serverless job cancelled before submission")
+                    continue
+                # Do not send two cancellation requests for the same live job in
+                # one action. Its unresolved reservation survives for later recovery.
+                if rid in targets or collector_job_id or not record.get("job_id"):
+                    continue
+                await self._recover_provider_record(record, cancel=True)
+                recovered += 1
+        await self._notify_capacity()
+        return len(targets) + recovered
+
+    def public_jobs(self, worker_id):
+        records = [record for record in reversed(self.ledger.all()) if belongs_to_pool(record, worker_id)]
+        # Never hide unresolved IDs behind the bounded completed history.
+        visible = [record for record in records if is_unresolved(record)]
+        visible.extend(record for record in records if not is_unresolved(record))
+        unresolved_count = sum(is_unresolved(record) for record in records)
+        return [{key: record.get(key) for key in ("record_id", "job_id", "status", "worker_id", "execution_id", "error")}
+                for record in visible[:max(20, unresolved_count)]]

api/orchestration/serverless_state.py

@@ -0,0 +1,29 @@
+"""Shared rules for provider capacity and durable recovery protection.
+
+A local task ending is not evidence that provider work ended. RESOLVED is an
+explicit operator acknowledgment, never a provider-reported state.
+"""
+
+PROVIDER_TERMINAL = frozenset({"COMPLETED", "FAILED", "CANCELLED", "TIMED_OUT"})
+TERMINAL = PROVIDER_TERMINAL | {"RESOLVED"}
+PROVIDER_STATES = PROVIDER_TERMINAL | {"IN_QUEUE", "IN_PROGRESS"}
+
+
+def terminal_provider_status(response):
+    status = response.get("status") if isinstance(response, dict) else None
+    return status if isinstance(status, str) and status in PROVIDER_TERMINAL else None
+
+
+def is_unresolved(record):
+    return record.get("status") not in TERMINAL
+
+
+def occupies_capacity(record):
+    # WAITING is journalled before admission and cannot have been submitted.
+    # Every other unresolved state is conservatively reserved, including a
+    # submission whose provider ID was lost and an unconfirmed cancellation.
+    return is_unresolved(record) and (record.get("status") != "WAITING" or bool(record.get("job_id")))
+
+
+def belongs_to_pool(record, worker_id):
+    return str(record.get("worker_id")) == str(worker_id)

api/queue_orchestration.py

@@ -21,7 +21,12 @@ from .orchestration.dispatch import (
     select_active_workers,
     select_least_busy_worker,
 )
-from .orchestration.media_sync import convert_paths_for_platform, fetch_worker_path_separator, sync_worker_media
+from .orchestration.media_sync import (
+    convert_paths_for_platform,
+    fetch_worker_has_node,
+    fetch_worker_path_separator,
+    sync_worker_media,
+)
 from .orchestration.prompt_transform import (
     PromptIndex,
     apply_participant_overrides,
@@ -29,6 +34,7 @@ from .orchestration.prompt_transform import (
     generate_job_id_map,
     prepare_delegate_master_prompt,
     prune_prompt_for_worker,
+    WORKER_SINK_CLASS,
 )
 
 
@@ -74,6 +80,14 @@ def _resolve_enabled_workers(config, requested_ids=None):
         elif not worker.get("enabled", False):
             continue
 
+        if worker.get("type") == "serverless":
+            from ..utils.serverless_config import validate_serverless_worker
+            pool = validate_serverless_worker(worker)
+            for slot in range(pool["jobs_per_run"]):
+                workers.append(dict(pool, pool_id=worker_id, id=f"serverless:{worker_id}:{slot + 1}",
+                                    name=f"{pool.get('name', worker_id)} / job {slot + 1}"))
+            continue
+
         raw_port = worker.get("port", worker.get("listen_port", 8188))
         try:
             port = int(raw_port or 8188)
@@ -154,6 +168,21 @@ async def _prepare_worker_payload(
     """Prepare one worker prompt payload with bounded concurrency and media-sync timeout."""
     async with worker_prep_semaphore:
         worker_prompt = prompt_index.copy_prompt()
+        if worker.get("type") == "serverless":
+            from .orchestration.serverless_prompt import compile_serverless_prompt
+            from .orchestration.serverless_media import prepare_images
+            from .orchestration.runpod_client import serialize_request
+            worker_prompt = apply_participant_overrides(
+                prune_prompt_for_worker(worker_prompt), worker["id"], enabled_ids,
+                job_id_map, "", delegate_master, prompt_index,
+            )
+            workflow, manifest = compile_serverless_prompt(worker_prompt)
+            images = await prepare_images(workflow)
+            # Fail during preparation, before regular workers or the master are
+            # dispatched. submit() uses this same serializer for the sent bytes.
+            serialize_request(workflow, images, worker["timeout_seconds"])
+            return worker, {"worker": worker, "workflow": workflow, "manifest": manifest, "images": images}
+
         worker_master_url = build_master_callback_url(
             worker,
             config=config,
@@ -162,12 +191,21 @@ async def _prepare_worker_payload(
 
         worker_type = str(worker.get("type") or "local").strip().lower()
         is_remote_like = bool(worker.get("host")) and worker_type != "local"
-        if is_remote_like:
-            path_separator = await fetch_worker_path_separator(worker, trace_execution_id=trace_execution_id)
-            if path_separator:
-                worker_prompt = convert_paths_for_platform(worker_prompt, path_separator)
+        # Older workers lack the sink node; they keep the PreviewImage terminator.
+        has_sink_task = asyncio.ensure_future(
+            fetch_worker_has_node(worker, WORKER_SINK_CLASS, trace_execution_id=trace_execution_id)
+        )
+        try:
+            if is_remote_like:
+                path_separator = await fetch_worker_path_separator(worker, trace_execution_id=trace_execution_id)
+                if path_separator:
+                    worker_prompt = convert_paths_for_platform(worker_prompt, path_separator)
+            use_worker_sink = await has_sink_task
+        finally:
+            if not has_sink_task.done():
+                has_sink_task.cancel()
 
-        worker_prompt = prune_prompt_for_worker(worker_prompt)
+        worker_prompt = prune_prompt_for_worker(worker_prompt, use_worker_sink=use_worker_sink)
         worker_prompt = apply_participant_overrides(
             worker_prompt,
             worker["id"],
@@ -330,9 +368,6 @@ async def orchestrate_distributed_execution(
             queue_result.get("node_errors", {}),
         )
 
-    for job_id in job_id_map.values():
-        await _ensure_distributed_queue(job_id)
-
     master_prompt = prompt_index.copy_prompt()
     master_prompt = apply_participant_overrides(
         master_prompt,
@@ -387,7 +422,19 @@ async def orchestrate_distributed_execution(
             ]
         )
 
-    if worker_payloads:
+    serverless_jobs = [payload for worker, payload in worker_payloads if worker.get("type") == "serverless"]
+    regular_payloads = [(worker, payload) for worker, payload in worker_payloads if worker.get("type") != "serverless"]
+    manager = None
+    if serverless_jobs:
+        from .orchestration.serverless_runtime import get_manager
+        manager = get_manager()
+        manager.ensure_capacity(len(serverless_jobs))
+
+    # Do not leave collector queues behind when offline compilation/media validation fails.
+    for job_id in job_id_map.values():
+        await _ensure_distributed_queue(job_id)
+
+    if regular_payloads:
         await asyncio.gather(
             *[
                 dispatch_worker_prompt(
@@ -398,17 +445,38 @@ async def orchestrate_distributed_execution(
                     use_websocket=use_websocket,
                     trace_execution_id=execution_trace_id,
                 )
-                for worker, wprompt in worker_payloads
+                for worker, wprompt in regular_payloads
             ]
         )
 
-    queue_result = await queue_prompt_payload(
-        master_prompt,
-        workflow_meta,
-        client_id,
-        include_queue_metadata=True,
-    )
+    try:
+        queue_result = await queue_prompt_payload(
+            master_prompt,
+            workflow_meta,
+            client_id,
+            include_queue_metadata=True,
+        )
+    except Exception:
+        if serverless_jobs:
+            async with prompt_server.distributed_jobs_lock:
+                for job_id in job_id_map.values():
+                    prompt_server.distributed_pending_jobs.pop(job_id, None)
+        raise
     prompt_id = queue_result["prompt_id"]
+    if manager is not None:
+        try:
+            await manager.start(execution_trace_id, prompt_id, serverless_jobs)
+        except Exception:
+            # Wake queued collectors with an explicit error if journal/capacity setup failed.
+            await manager.cancel(execution_id=execution_trace_id)
+            async with prompt_server.distributed_jobs_lock:
+                for prepared in serverless_jobs:
+                    for binding in prepared["manifest"]:
+                        q = prompt_server.distributed_pending_jobs.get(binding["job_id"])
+                        if q is not None:
+                            q.put_nowait({"worker_id": prepared["worker"]["id"], "is_last": True,
+                                          "serverless_error": "Serverless job setup failed; no automatic retry was attempted"})
+            raise
     prompt_number = queue_result["number"]
     node_errors = queue_result.get("node_errors", {})
     trace_debug(

api/serverless_routes.py

@@ -0,0 +1,98 @@
+"""Master-only Runpod pool monitoring. Health checks never submit inference."""
+from aiohttp import web
+import server
+
+from ..utils.config import load_config
+from .orchestration.serverless_runtime import get_manager
+from .orchestration.runpod_client import RunpodError
+
+
+def _pool(worker_id):
+    return next((w for w in load_config().get("workers", [])
+                 if w.get("id") == worker_id and w.get("type") == "serverless"), None)
+
+
+async def _status(worker_id, fresh=False):
+    worker = _pool(worker_id)
+    if worker is None:
+        return web.json_response({"ok": False, "message": "Serverless worker not found"}, status=404)
+    jobs = []
+    try:
+        manager = get_manager()
+        jobs = manager.public_jobs(worker_id)
+        result = await manager.health(worker, fresh=fresh)
+        return web.json_response(dict(result, jobs=jobs))
+    except Exception as exc:
+        message = str(exc) if isinstance(exc, RunpodError) else "Check the saved endpoint ID and API key"
+        return web.json_response({"ok": False, "queueRemaining": 0, "message": message, "jobs": jobs})
+
+
+@server.PromptServer.instance.routes.post("/distributed/serverless/test")
+async def test_serverless_endpoint(request):
+    try:
+        data = await request.json()
+        worker_id = data.get("worker_id")
+    except Exception:
+        return web.json_response({"ok": False, "message": "Invalid request"}, status=400)
+    return await _status(worker_id, fresh=True)
+
+
+@server.PromptServer.instance.routes.get("/distributed/serverless/status/{worker_id}")
+async def serverless_status_endpoint(request):
+    return await _status(request.match_info["worker_id"])
+
+
+@server.PromptServer.instance.routes.post("/distributed/serverless/cancel")
+async def cancel_serverless_endpoint(request):
+    try:
+        data = await request.json()
+        worker_id = data.get("worker_id")
+    except Exception:
+        return web.json_response({"ok": False, "message": "Invalid request"}, status=400)
+    if _pool(worker_id) is None:
+        return web.json_response({"ok": False, "message": "Serverless worker not found"}, status=404)
+    try:
+        manager = get_manager()
+        count = await manager.cancel(worker_id=worker_id)
+        return web.json_response({"ok": True, "cancelled": count, "jobs": manager.public_jobs(worker_id),
+                                  "message": "Cancellation requested for this master's jobs only"})
+    except Exception:
+        return web.json_response({"ok": False, "message": "Cancellation could not be confirmed; check provider jobs"}, status=502)
+
+
+async def _recover(request, *, acknowledge=False):
+    try:
+        data = await request.json()
+        worker_id = data.get("worker_id")
+        if not isinstance(worker_id, str) or not worker_id.strip():
+            raise ValueError()
+        record_id = data.get("record_id")
+        if acknowledge:
+            if not isinstance(record_id, str) or not record_id.strip() or data.get("provider_checked") is not True:
+                raise ValueError()
+    except Exception:
+        return web.json_response({"ok": False, "message": "Provide a worker ID; manual resolution also requires a record ID and provider_checked: true"}, status=400)
+    if _pool(worker_id) is None:
+        return web.json_response({"ok": False, "message": "Serverless worker not found"}, status=404)
+    try:
+        manager = get_manager()
+        if acknowledge:
+            await manager.acknowledge_recovery(worker_id, record_id, provider_checked=True)
+            result = {"message": "Recovery acknowledged by operator; not provider-confirmed cancellation"}
+        else:
+            result = {"resolved": await manager.reconcile(worker_id=worker_id)}
+        return web.json_response(dict(result, ok=True, jobs=manager.public_jobs(worker_id)))
+    except ValueError:
+        return web.json_response({"ok": False, "message": "Unresolved inactive job not found for this worker"}, status=409)
+    except Exception:
+        return web.json_response({"ok": False, "message": "Recovery could not be confirmed; retained jobs remain protected"}, status=502)
+
+
+@server.PromptServer.instance.routes.post("/distributed/serverless/reconcile")
+async def reconcile_serverless_endpoint(request):
+    return await _recover(request)
+
+
+@server.PromptServer.instance.routes.post("/distributed/serverless/resolve")
+async def resolve_serverless_endpoint(request):
+    return await _recover(request, acknowledge=True)

api/worker_routes.py

@@ -16,12 +16,14 @@ from ..utils.logging import debug_log, log
 from ..utils.network import (
     build_worker_url,
     get_client_session,
+    get_server_port,
     handle_api_error,
     normalize_host,
     probe_worker,
 )
 from ..utils.constants import CHUNK_SIZE
 from ..workers import get_worker_manager
+from ..workers.ports import allocate_worker_ports
 from .schemas import require_fields, validate_worker_id
 from ..workers.detection import (
     get_machine_id,
@@ -277,6 +279,13 @@ def _get_cuda_info():
 def _collect_network_info_sync():
     """Collect network/cuda info in a worker thread to avoid blocking route handlers."""
     cuda_device, cuda_device_count, physical_device_count = _get_cuda_info()
+    device_count = physical_device_count if physical_device_count > 0 else cuda_device_count
+    master_port = get_server_port()
+    config = load_config()
+    worker_ports = []
+    if not config.get("settings", {}).get("has_auto_populated_workers") and not config.get("workers"):
+        worker_count = device_count - (1 if cuda_device is not None and 0 <= cuda_device < device_count else 0)
+        worker_ports = allocate_worker_ports(master_port, config.get("workers", []), worker_count)
     hostname = socket.gethostname()
     all_ips = get_network_ips()
     recommended_ip = get_recommended_ip(all_ips)
@@ -285,7 +294,9 @@ def _collect_network_info_sync():
         "all_ips": all_ips,
         "recommended_ip": recommended_ip,
         "cuda_device": cuda_device,
-        "cuda_device_count": physical_device_count if physical_device_count > 0 else cuda_device_count,
+        "cuda_device_count": device_count,
+        "master_port": master_port,
+        "local_worker_ports": worker_ports,
     }
 
 
@@ -449,6 +460,9 @@ async def launch_worker_endpoint(request):
         if not worker:
             return await handle_api_error(request, f"Worker {worker_id} not found", 404)
         
+        if worker.get("type") == "serverless":
+            return await handle_api_error(request, "Serverless workers are managed by Runpod, not local processes", 400)
+
         # Ensure consistent string ID
         worker_id_str = worker_id
         
@@ -483,6 +497,8 @@ async def launch_worker_endpoint(request):
                 "message": f"Worker {worker['name']} launched",
                 "log_file": log_file
             })
+        except ValueError as e:
+            return await handle_api_error(request, f"Failed to launch worker: {str(e)}", 400)
         except Exception as e:
             return await handle_api_error(request, f"Failed to launch worker: {str(e)}", 500)
             
@@ -541,6 +557,9 @@ async def get_local_worker_status_endpoint(request):
         worker_statuses = {}
         
         for worker in config.get("workers", []):
+            # Serverless pools have no host, port, or local process.
+            if worker.get("type") == "serverless":
+                continue
             # Only check local workers
             host = normalize_host(worker.get("host")) or ""
             if not host or host in ["localhost", "127.0.0.1"]:

conftest.py

@@ -1,7 +1,7 @@
 # conftest.py — project-level pytest configuration.
 #
 # Problem: custom_nodes/ComfyUI-Distributed/__init__.py uses relative imports
-# (from .distributed import ...) that fail when pytest tries to import it as a
+# (from .nodes.v3 import ...) that fail when pytest tries to import it as a
 # standalone module during Package.setup() for the root package node.
 #
 # Fix: patch Package.setup() to skip the root-package's __init__.py import.

distributed.py

@@ -1,51 +0,0 @@
-"""
-ComfyUI-Distributed: thin entry point.
-All implementation lives in workers/, nodes/, api/.
-"""
-import atexit
-import os
-
-import server
-
-from .utils.config import ensure_config_exists
-from .utils.logging import debug_log
-from .utils.network import cleanup_client_session
-from .workers import get_worker_manager
-from .workers.startup import delayed_auto_launch, register_async_signals, sync_cleanup
-from .upscale.job_store import ensure_tile_jobs_initialized
-from .nodes import (
-    NODE_CLASS_MAPPINGS,
-    NODE_DISPLAY_NAME_MAPPINGS,
-    ImageBatchDivider,
-    DistributedCollectorNode,
-    DistributedSeed,
-    DistributedModelName,
-    DistributedValue,
-    AudioBatchDivider,
-    DistributedEmptyImage,
-    AnyType,
-    ByPassTypeTuple,
-    any_type,
-)
-from . import api  # noqa: F401 - triggers all @routes.* registrations
-from .api.queue_orchestration import ensure_distributed_state
-
-ensure_config_exists()
-
-# Aiohttp session cleanup
-async def _cleanup_session():
-    await cleanup_client_session()
-
-
-atexit.register(lambda: None)  # placeholder; real cleanup in sync_cleanup
-
-# Initialize distributed job state on prompt_server
-prompt_server = server.PromptServer.instance
-ensure_distributed_state(prompt_server)
-ensure_tile_jobs_initialized()
-
-# Worker startup
-if not os.environ.get('COMFYUI_IS_WORKER'):
-    atexit.register(sync_cleanup)
-    delayed_auto_launch()
-    register_async_signals()

docs/compressed-result-transfer.md

@@ -0,0 +1,38 @@
+# Compressed Result Transfer
+
+**Distributed Collector** has two optional widgets that control how workers send their images back to the master. This matters most when workers run in the cloud and you pay for data leaving it (egress).
+
+| `transfer_format` | Type | Notes |
+|---|---|---|
+| `legacy_png` (default) | lossless | Original behaviour: one JSON request per frame, uncompressed PNG in base64. Works with any master version. |
+| `png` | lossless | Compressed PNG, binary, several frames per request. Same tensors as `legacy_png`. |
+| `ffv1` | lossless | Whole batch as one FFV1 video. Same tensors as `legacy_png`; best lossless choice for frame sequences. |
+| `jpeg`, `webp` | lossy | Per-frame stills. Good for image batches. |
+| `h264`, `h265`, `av1` | lossy | Whole batch as one video. By far the smallest for video frame batches. |
+
+`transfer_quality` (1–100, default 90) applies to the lossy formats. JPEG/WebP use it directly; video codecs map it to CRF (90 → CRF 13 for h264/h265, CRF 16 for av1; 100 → CRF 0).
+
+Measured on a 121-frame 1280×720 batch (one worker's result):
+
+| Format | Sent | vs legacy | PSNR |
+|---|---|---|---|
+| `legacy_png` | 446 MB | 1× | lossless |
+| `png` | 163 MB | 2.7× | lossless |
+| `ffv1` | 128 MB | 3.5× | lossless |
+| `jpeg` q90 | 27 MB | 17× | 42.7 dB |
+| `webp` q90 | 13 MB | 33× | 40.6 dB |
+| `h264` q90 | 2.4 MB | 186× | 40.2 dB |
+| `h265` q90 | 1.0 MB | 434× | 40.1 dB |
+| `av1` q90 | 0.4 MB | 1031× | 40.5 dB |
+
+The test clip is a slow pan, which video codecs compress especially well; expect smaller (still large) gains on content with more motion.
+
+Notes:
+- Choose the format on the master; the value is sent to workers with the workflow.
+- The master must run this version to accept compressed results. A worker sending to an older master gets a 400 on its first request and automatically resends with `legacy_png`.
+- If a worker's PyAV build lacks the requested video encoder, it falls back to `h264` (lossy formats) or `png` (`ffv1`), and logs it.
+- Lossy formats only affect frames produced by workers; the master's own frames are never re-encoded.
+- Request size is bounded on the final encoded bytes. Frames are batched into requests of up to 32 MiB (`COMFYUI_DISTRIBUTED_TRANSFER_CHUNK_BYTES`); a single large frame may go alone in a request of up to 96 MiB (`COMFYUI_DISTRIBUTED_TRANSFER_MAX_REQUEST_BYTES`). Keep the latter below the master's `--max-upload-size` (default 100 MB) if you change either.
+- All chunks are encoded before anything is sent. If a single frame cannot fit within the request limit, the worker fails with an error and sends nothing; use a lossy format or raise both limits.
+- A rejection other than the older-master case above (for example the master's size limit, HTTP 413) is reported as an error rather than retried as `legacy_png`.
+- Each worker logs what it sent, e.g. `Sent 121 image(s) as h264 in 1 request(s): 2.40 MB (raw 334.49 MB, 139.4x smaller)`.

docs/serverless-workers.md

@@ -0,0 +1,173 @@
+# Runpod serverless workers (preview)
+
+A **Serverless (Runpod)** worker is a queue-based endpoint, not a permanent
+ComfyUI machine. Runpod chooses the actual GPU workers. Distributed submits one
+normal ComfyUI API workflow per requested image and collects the returned images.
+The endpoint workers **do not need ComfyUI-Distributed installed**.
+
+## Setup
+
+1. Add a worker in the Distributed panel and select **Serverless (Runpod)**.
+2. Enter its name, Runpod **endpoint ID** (not a URL; a pasted `https://api.runpod.ai/v2/<id>/…`
+   URL is trimmed to the ID), and API key.
+3. Start with **Images per run = 1** and **Timeout = 1800**.
+4. Save, then choose **Test Saved Endpoint**. This checks authentication and
+   endpoint health only; it does not start GPU inference or prove model/node compatibility.
+5. Enable the worker when you want queued Distributed workflows to use it.
+6. Use an image **Distributed Collector** and queue through Distributed as usual.
+   Enable **Delegate Only** if the master should collect without generating locally.
+
+Keys are write-only. Leave the key field blank to retain a saved key, or select
+**Clear saved API key** to remove it. The checkbox is unavailable while the
+worker is enabled, so turn the worker off first. A saved key is required before
+enabling a worker. Use HTTPS or a trusted local connection when
+entering keys. Like ComfyUI itself, the panel must not be exposed to untrusted
+users: anyone able to queue arbitrary workflows can run code and spend endpoint credits.
+
+## Endpoint contract
+
+The endpoint must accept this generic input shape; named application modes are
+not used:
+
+```json
+{
+  "input": {
+    "workflow": {
+      "1": {"class_type": "EmptyImage", "inputs": {"width": 32, "height": 32, "batch_size": 1, "color": 0}},
+      "2": {"class_type": "SaveImage", "inputs": {"images": ["1", 0], "filename_prefix": "example"}}
+    },
+    "images": []
+  }
+}
+```
+
+For image inputs, `images` contains `{ "name": "input.png", "image": "<base64>" }`
+entries and the handler must rewrite `LoadImage` references to the staged files.
+The adapter transfers local input images; it does not copy models or install nodes.
+All referenced models and custom nodes must already exist in the endpoint image.
+
+On completion, Runpod's `output.images` must contain artifact records such as:
+
+```json
+{
+  "filename": "example_00001_.png",
+  "subfolder": "",
+  "artifact_type": "output",
+  "artifact_path": "example_00001_.png",
+  "type": "base64",
+  "data": "<base64>"
+}
+```
+
+Image data can alternatively use `type: "s3_url"`, `"gcs_url"`, or `"url"`
+with an HTTPS URL in `data`/`url`. Signed artifact URLs are downloaded without
+Runpod credentials; private-network destinations and unsafe redirects are refused.
+The handler must preserve injected `SaveImage.filename_prefix` values so results
+can be matched to the right collector and slot. Duplicate basenames in different
+subfolders remain different artifact identities.
+
+A Runpod job marked `COMPLETED` is still rejected if `output.error` or
+`output.errors` is nonempty, required collector outputs are missing, or image
+artifacts are invalid. Failures are surfaced rather than silently returning an
+incomplete serverless batch.
+
+## Scheduling and cancellation
+
+- **Images per run** (1–16) is how many separate Runpod jobs this worker submits
+  for each queued run. Each returns one image and receives its own Distributed
+  Seed/Value overrides. All of them are submitted at once.
+- How many of those jobs actually run in parallel is decided by the Runpod
+  endpoint's **max workers**, not by Distributed. Jobs beyond that wait in
+  Runpod's queue. To run every image at the same time, keep Images per run at or
+  below the endpoint's max workers.
+- Distributed also keeps a fixed limit of 16 outstanding jobs per serverless
+  worker (and 64 across all of them). Retained jobs after a restart, ambiguous
+  submissions, and unconfirmed cancellations keep counting against it until
+  reconciled. Other applications using the same endpoint are unaffected.
+- Older configs may contain a `concurrency` field from the previous separate
+  setting. It is still accepted when loading or saving, but ignored and dropped.
+- **Load balance** selects one participant, so it sends one job instead of
+  Images per run.
+- **Timeout** includes Runpod queue/cold-start time, execution, and output
+  retrieval. Provider policy limits are submitted as well.
+- A zero-worker endpoint can be healthy: Runpod scales from zero on submission.
+- Interrupting a collector or using the panel cancellation action requests
+  cancellation only for jobs submitted by this master. It never purges the endpoint.
+- A network failure during submission is **not retried automatically**: the job
+  may already be billable. Check the Runpod job list before queuing again.
+
+## Persistence and recovery
+
+Credentials live outside `gpu_config.json` and Git in the master ComfyUI user
+folder under `distributed/serverless/credentials.json`, with restrictive POSIX
+permissions. They are omitted from public configuration, workflow exports, and
+browser configuration state. The first version requires a POSIX (Linux/macOS)
+master for serverless secret storage; existing non-serverless workers remain
+available on Windows.
+
+`distributed/serverless/jobs.json` records provider job IDs and sanitized states,
+not image data, workflow payloads, or API keys. A restarted master cannot resume
+an interrupted collector. It does **not** automatically resubmit jobs. Retained
+IDs are available through `/distributed/serverless/status/<worker_id>`; the worker's
+cancel action can request cancellation of known pre-restart jobs. If no job ID
+was received, check Runpod manually. Cancellation is best-effort and may race
+with completion; `CANCEL_REQUESTED` is not a provider-confirmed cancellation.
+
+Unresolved records protect the worker's endpoint, API key, worker type,
+and deletion even when no local task remains. Disabling the worker is still allowed;
+it does not cancel existing jobs. On restart, never-submitted `WAITING` slots are
+closed locally, while interrupted `SUBMITTING` records without IDs become
+`UNKNOWN` and remain protected.
+
+### Reconcile or acknowledge recovery
+
+Recovery uses the same trusted-master API as the panel; it never resubmits a job.
+
+1. Read `GET /distributed/serverless/status/<worker_id>`. The `jobs` list includes
+   every unresolved record with its local `record_id`, provider `job_id` (if
+   received), and state. These records remain visible if endpoint health fails.
+2. Request cancellation from the panel, or send
+   `POST /distributed/serverless/reconcile` with the body below to **read** the
+   retained provider IDs. Only a confirmed terminal state releases protection.
+   Network errors, expired IDs, or ambiguous responses do not.
+
+   ```json
+   {"worker_id": "YOUR_WORKER_ID"}
+   ```
+
+3. If no ID was returned, or Runpod no longer retains its status, inspect Runpod
+   manually first. **Only after verifying that the job is no longer running or
+   queued**, send `POST /distributed/serverless/resolve` for that one record:
+
+   ```json
+   {"worker_id": "YOUR_WORKER_ID", "record_id": "LOCAL_RECORD_ID", "provider_checked": true}
+   ```
+
+   This records `RESOLVED`: an explicit operator acknowledgment, **not** a
+   provider-confirmed cancellation. It cannot resolve a live local task and does
+   not stop remote compute. It releases the record's reservation and may let
+   already-waiting jobs proceed. Never automate this acknowledgment as a retry
+   mechanism; an unverified job can still be billable.
+
+Worker setting changes become available once all its local tasks and unresolved records
+are finished. No credentials or ledger files need to be edited by hand.
+
+## First-version limits
+
+- Image collectors only. Audio/video transfer and audio collectors are rejected.
+- Coordinated `UltimateSDUpscaleDistributed` workloads and unsupported Distributed
+  node types are rejected before submission.
+- Downstream post-collector processing remains local; the remote graph contains
+  only the upstream compute required for image saves.
+- Inputs must be supported images under ComfyUI's input/output/temp roots.
+- Raw image input reads are guarded at 10,000,000 bytes total, and the complete
+  serialized `/run` JSON request body (workflow, base64 images, and policy) must
+  also fit within 10,000,000 bytes. Base64 adds about 33%, so the usable raw-image
+  budget is lower and depends on workflow size. Large-media/object-storage upload
+  support is not included.
+- No remote GPU discovery, endpoint provisioning, model synchronization, automatic
+  scaling changes, or inbound master callback/tunnel is needed.
+
+This feature is verified with offline provider/transport tests. A successful
+health test is not a paid end-to-end generation test; test your deployed handler
+and model inventory with one image per run before increasing it.

docs/v3-migration.md

@@ -0,0 +1,53 @@
+# Native V3 node API
+
+The package registers one `ComfyExtension` through `comfy_entrypoint()` and
+imports the versioned `comfy_api.v0_0_2` API. Use a ComfyUI version that provides
+that API; there is no V1 registration fallback.
+
+## Compatibility
+
+- All eight node IDs, display names, categories, visible input order, defaults
+  and output order are retained. Existing execution algorithms remain in the
+  private collector, utilities and upscale modules.
+- The image/audio dividers explicitly declare ten typed outputs. Their existing
+  frontend extensions still show only the selected number of outputs. This
+  replaces the V1 `ByPassTypeTuple` indexing workaround without changing saved
+  IMAGE/AUDIO socket indices or the ten returned values.
+- Standard hidden context uses `cls.hidden`. Worker/orchestration metadata keeps
+  its existing prompt-input names and Python defaults via `accept_all_inputs`;
+  it does not become visible widgets.
+- The collector retains list-input handling. Upscale retains its always-changing
+  fingerprint and creates a private runtime helper for each V3 execution, so
+  mutable helper state is not attached to sanitized V3 class clones.
+- Routes, distributed state and the existing worker startup/shutdown hooks are
+  initialized by `runtime/bootstrap.py` during `ComfyExtension.on_load()`.
+  Worker mode still suppresses automatic worker launch. `distributed.py` is no
+  longer an entrypoint.
+
+## Verification
+
+Run ordinary unit tests from this repository:
+
+```bash
+python -m pytest tests -q -o addopts=
+```
+
+Opt into real-framework acceptance using a ComfyUI checkout and its interpreter:
+
+```bash
+COMFYUI_SOURCE_ROOT=/path/to/ComfyUI \
+  /path/to/ComfyUI/.venv/bin/python -m pytest tests -q -o addopts=
+```
+
+The acceptance subprocess uses CPU mode and the real ComfyUI loader, input
+parser, V3 class preparation, prompt validation and `PromptExecutor`. It compares
+all node schemas with the V1 fixture, checks all five bundled workflows' node
+IDs and socket/link contracts, exercises injected worker metadata, image/audio
+lists, collector aggregation and divider outputs, rejects invalid upscale enums,
+and decodes an actual preview PNG referenced by executor history.
+
+The upscale GPU/model boundary is mocked to check argument forwarding and
+per-execution helper isolation. Full checkpoint inference, browser canvas
+acceptance and multi-host HTTP transport are not exercised. No HTTP listener,
+workers or model downloads are started; preview files use a temporary scratch
+directory. The test does not install this branch into a live custom-node folder.

docs/worker-setup-guides.md

@@ -74,6 +74,8 @@ The master can either contribute GPU work or stay in **orchestrator-only** mode:
 
 > ComfyUI instances running on a cloud service like Runpod. 
 
+For faster result transfers and lower bandwidth usage, see [Compressed Result Transfer](compressed-result-transfer.md).
+
 ### Deploy Cloud Worker on Runpod
 
 📺 [Watch Tutorial](https://www.youtube.com/watch?v=wxKKWMQhYTk)

nodes/__init__.py

@@ -1,31 +1 @@
-from .utilities import (
-    DistributedSeed,
-    DistributedModelName,
-    DistributedValue,
-    ImageBatchDivider,
-    AudioBatchDivider,
-    DistributedEmptyImage,
-    AnyType,
-    ByPassTypeTuple,
-    any_type,
-)
-from .collector import DistributedCollectorNode
-
-NODE_CLASS_MAPPINGS = {
-    "DistributedCollector": DistributedCollectorNode,
-    "DistributedSeed": DistributedSeed,
-    "DistributedModelName": DistributedModelName,
-    "DistributedValue": DistributedValue,
-    "ImageBatchDivider": ImageBatchDivider,
-    "AudioBatchDivider": AudioBatchDivider,
-    "DistributedEmptyImage": DistributedEmptyImage,
-}
-NODE_DISPLAY_NAME_MAPPINGS = {
-    "DistributedCollector": "Distributed Collector",
-    "DistributedSeed": "Distributed Seed",
-    "DistributedModelName": "Distributed Model Name",
-    "DistributedValue": "Distributed Value",
-    "ImageBatchDivider": "Image Batch Divider",
-    "AudioBatchDivider": "Audio Segment Divider",
-    "DistributedEmptyImage": "Distributed Empty Image",
-}
+"""Private execution helpers; public registration lives in nodes.v3."""

nodes/collector.py

@@ -12,15 +12,21 @@ from comfy.utils import ProgressBar
 
 from ..utils.logging import debug_log, log
 from ..utils.config import get_worker_timeout_seconds, load_config, is_master_delegate_only
-from ..utils.constants import HEARTBEAT_INTERVAL
+from ..utils.constants import HEARTBEAT_INTERVAL, TRANSFER_MAX_CHUNK_BYTES, TRANSFER_MAX_REQUEST_BYTES
 from ..utils.image import tensor_to_pil, pil_to_tensor, ensure_contiguous
 from ..utils.network import build_worker_url, get_client_session, probe_worker
 from ..utils.audio_payload import encode_audio_payload
 from ..utils.async_helpers import run_async_in_server_loop
+from ..utils import transfer_codec
 
 prompt_server = _server.PromptServer.instance
 
 
+def _encode_all_chunks(frames, fmt, quality, max_chunk_bytes, max_frame_bytes):
+    """Materialize every transfer chunk (runs in an executor)."""
+    return list(transfer_codec.encode_chunks(frames, fmt, quality, max_chunk_bytes, max_frame_bytes))
+
+
 class DistributedCollectorNode:
     INPUT_IS_LIST = True
     EMPTY_AUDIO = {"waveform": torch.zeros(1, 2, 1), "sample_rate": 44100}
@@ -40,6 +46,23 @@ class DistributedCollectorNode:
             "optional": {
                 "images": ("IMAGE",),
                 "audio": ("AUDIO",),
+                "transfer_format": (
+                    list(transfer_codec.TRANSFER_FORMATS),
+                    {
+                        "default": transfer_codec.DEFAULT_TRANSFER_FORMAT,
+                        "tooltip": transfer_codec.TRANSFER_FORMAT_TOOLTIP,
+                    },
+                ),
+                "transfer_quality": (
+                    "INT",
+                    {
+                        "default": transfer_codec.DEFAULT_TRANSFER_QUALITY,
+                        "min": 1,
+                        "max": 100,
+                        "step": 1,
+                        "tooltip": transfer_codec.TRANSFER_QUALITY_TOOLTIP,
+                    },
+                ),
             },
             "hidden": {
                 "multi_job_id": ("STRING", {"default": ""}),
@@ -104,7 +127,7 @@ class DistributedCollectorNode:
             return None
         return {"waveform": torch.cat(waveforms, dim=-1), "sample_rate": sample_rate}
 
-    def run(self, images=None, load_balance=False, audio=None, multi_job_id="", is_worker=False, master_url="", enabled_worker_ids="[]", worker_batch_size=1, worker_id="", pass_through=False, delegate_only=False):
+    def run(self, images=None, load_balance=False, audio=None, multi_job_id="", is_worker=False, master_url="", enabled_worker_ids="[]", worker_batch_size=1, worker_id="", pass_through=False, delegate_only=False, transfer_format=transfer_codec.DEFAULT_TRANSFER_FORMAT, transfer_quality=transfer_codec.DEFAULT_TRANSFER_QUALITY):
         if images is not None:
             images = self._normalize_images_input(images)
         audio = self._normalize_audio_input(audio)
@@ -117,6 +140,8 @@ class DistributedCollectorNode:
         worker_id = self._unwrap_list_input(worker_id)
         pass_through = self._unwrap_list_input(pass_through)
         delegate_only = self._unwrap_list_input(delegate_only)
+        transfer_format = self._unwrap_list_input(transfer_format)
+        transfer_quality = self._unwrap_list_input(transfer_quality)
 
         remote_only_master = (
             bool(multi_job_id)
@@ -147,12 +172,181 @@ class DistributedCollectorNode:
                 worker_batch_size,
                 worker_id,
                 delegate_only,
+                transfer_format,
+                transfer_quality,
             )
         )
         return result
 
-    async def send_batch_to_master(self, image_batch, audio, multi_job_id, master_url, worker_id):
+    @staticmethod
+    def _get_serverless_manager():
+        """Return the serverless manager only for collector jobs with serverless slots."""
+        manager = getattr(prompt_server, "distributed_serverless", None)
+        if manager is not None:
+            return manager
+        from ..api.orchestration.serverless_runtime import get_manager
+        return get_manager()
+
+    async def send_batch_to_master(
+        self,
+        image_batch,
+        audio,
+        multi_job_id,
+        master_url,
+        worker_id,
+        transfer_format=transfer_codec.DEFAULT_TRANSFER_FORMAT,
+        transfer_quality=transfer_codec.DEFAULT_TRANSFER_QUALITY,
+    ):
         """Send an image batch, optionally with audio, or an audio-only completion."""
+        batch_size = 0 if image_batch is None else image_batch.shape[0]
+        fmt = self._resolve_transfer_format(transfer_format) if batch_size else transfer_codec.LEGACY_FORMAT
+        if fmt != transfer_codec.LEGACY_FORMAT:
+            sent = await self._send_compressed_batch(
+                image_batch, audio, multi_job_id, master_url, worker_id, fmt, transfer_quality
+            )
+            if sent:
+                return
+            log(
+                "Worker - Master did not accept compressed transfer "
+                "(older ComfyUI-Distributed on the master?). Falling back to legacy_png."
+            )
+        await self._send_legacy_batch(image_batch, audio, multi_job_id, master_url, worker_id)
+
+    @staticmethod
+    def _resolve_transfer_format(transfer_format):
+        try:
+            fmt = transfer_codec.normalize_format(transfer_format)
+        except transfer_codec.TransferCodecError as exc:
+            log(f"Worker - {exc}; using legacy_png.")
+            return transfer_codec.LEGACY_FORMAT
+        if fmt not in transfer_codec.VIDEO_FORMATS or transfer_codec.video_codec_available(fmt):
+            return fmt
+        fallback = "h264" if fmt != "ffv1" and transfer_codec.video_codec_available("h264") else "png"
+        log(f"Worker - Encoder for '{fmt}' is not available in this PyAV build; using '{fallback}'.")
+        return fallback
+
+    @staticmethod
+    def _build_multipart(envelope, parts):
+        form = aiohttp.FormData()
+        form.add_field("envelope", json.dumps(envelope), content_type="application/json")
+        for i, data in enumerate(parts):
+            form.add_field("media", data, filename=f"{i}.bin", content_type="application/octet-stream")
+        return form
+
+    # Room left in each request for the multipart envelope (ids, frame
+    # metadata, part headers). Audio is budgeted separately.
+    TRANSFER_ENVELOPE_RESERVE_BYTES = 256 * 1024
+    # Body of a 400 from a master without compressed-transfer support: it
+    # tries request.json() on the multipart body and fails.
+    _OLD_MASTER_REJECTION = "Invalid JSON payload"
+
+    async def _send_compressed_batch(self, image_batch, audio, multi_job_id, master_url, worker_id, fmt, quality):
+        """Send the batch as compressed multipart chunks.
+
+        All chunks are encoded before anything is sent, so a frame that cannot
+        fit in one request fails the transfer without delivering a partial
+        batch. Every request stays within TRANSFER_MAX_REQUEST_BYTES.
+
+        Returns False (without having delivered anything) when the master
+        rejects the first chunk because it predates compressed transfer, so
+        the caller can retry with legacy_png. Any other rejection raises.
+        """
+        encoded_audio = encode_audio_payload(audio)
+        session = await get_client_session()
+        url = f"{master_url}/distributed/job_complete"
+        loop = asyncio.get_running_loop()
+
+        frames = await loop.run_in_executor(None, transfer_codec.tensor_batch_to_uint8, image_batch)
+        raw_bytes = int(frames.nbytes)
+        total = int(frames.shape[0])
+        media_limit = max(1, TRANSFER_MAX_REQUEST_BYTES - self.TRANSFER_ENVELOPE_RESERVE_BYTES)
+        started = time.time()
+        # Encoding is CPU-bound (seconds for video); keep the server loop responsive.
+        chunks = await loop.run_in_executor(
+            None, _encode_all_chunks, frames, fmt, quality, min(TRANSFER_MAX_CHUNK_BYTES, media_limit), media_limit,
+        )
+        del frames
+
+        # Attach audio to the final chunk only if the request stays in bounds;
+        # otherwise finish with a separate audio-only completion.
+        audio_bytes = len(json.dumps(encoded_audio)) if encoded_audio is not None else 0
+        last_media = sum(len(p) for p in chunks[-1]["parts"])
+        audio_inline = encoded_audio is not None and last_media + audio_bytes <= media_limit
+        audio_separate = encoded_audio is not None and not audio_inline
+
+        sent_bytes = 0
+        for index, chunk in enumerate(chunks):
+            parts = chunk.pop("parts")
+            is_final_chunk = index == len(chunks) - 1
+            envelope = {
+                "job_id": str(multi_job_id),
+                "worker_id": str(worker_id),
+                "is_last": bool(is_final_chunk and not audio_separate),
+                **chunk,
+            }
+            if is_final_chunk and audio_inline:
+                envelope["audio"] = encoded_audio
+            chunk_bytes = sum(len(p) for p in parts)
+            timeout_seconds = min(600, 60 + chunk_bytes // (256 * 1024))
+            try:
+                async with session.post(
+                    url,
+                    data=self._build_multipart(envelope, parts),
+                    timeout=aiohttp.ClientTimeout(total=timeout_seconds),
+                ) as response:
+                    if response.status >= 400:
+                        body = await response.text()
+                        if index == 0 and response.status == 400 and self._OLD_MASTER_REJECTION in body:
+                            debug_log(f"Worker - Master rejected compressed chunk: {body[:300]}")
+                            return False
+                        raise RuntimeError(
+                            f"Master rejected {fmt} chunk {index + 1}/{len(chunks)} "
+                            f"({chunk_bytes} bytes) with HTTP {response.status}: {body[:300]}. "
+                            "If this is a size limit, make COMFYUI_DISTRIBUTED_TRANSFER_MAX_REQUEST_BYTES "
+                            "on the worker smaller than the master's --max-upload-size."
+                        )
+            except Exception as e:
+                log(f"Worker - Failed to send {fmt} chunk to master: {e}")
+                debug_log(f"Worker - Full error details: URL={url}")
+                raise
+            sent_bytes += chunk_bytes
+
+        requests = len(chunks)
+        if audio_separate:
+            await self._post_json_completion(session, url, {
+                "job_id": str(multi_job_id),
+                "worker_id": str(worker_id),
+                "batch_idx": 0,
+                "audio": encoded_audio,
+                "is_last": True,
+            })
+            requests += 1
+
+        log(
+            f"Worker - Sent {total} image(s) as {fmt} in {requests} request(s): "
+            f"{sent_bytes / 1e6:.2f} MB (raw {raw_bytes / 1e6:.2f} MB, "
+            f"{transfer_codec.describe_ratio(sent_bytes, raw_bytes)} smaller) in {time.time() - started:.1f}s"
+        )
+        return True
+
+    @staticmethod
+    async def _post_json_completion(session, url, payload):
+        timeout_seconds = 60 if "image" in payload else 600
+        try:
+            async with session.post(
+                url,
+                json=payload,
+                timeout=aiohttp.ClientTimeout(total=timeout_seconds),
+            ) as response:
+                response.raise_for_status()
+        except Exception as e:
+            media_type = "image/audio" if "image" in payload else "audio-only"
+            log(f"Worker - Failed to send canonical {media_type} envelope to master: {e}")
+            debug_log(f"Worker - Full error details: URL={url}")
+            raise
+
+    async def _send_legacy_batch(self, image_batch, audio, multi_job_id, master_url, worker_id):
+        """Original transfer: one JSON request per frame with a base64 PNG."""
         encoded_audio = encode_audio_payload(audio)
         session = await get_client_session()
         url = f"{master_url}/distributed/job_complete"
@@ -189,19 +383,7 @@ class DistributedCollectorNode:
                 payloads.append(payload)
 
         for payload in payloads:
-            timeout_seconds = 60 if "image" in payload else 600
-            try:
-                async with session.post(
-                    url,
-                    json=payload,
-                    timeout=aiohttp.ClientTimeout(total=timeout_seconds),
-                ) as response:
-                    response.raise_for_status()
-            except Exception as e:
-                media_type = "image/audio" if "image" in payload else "audio-only"
-                log(f"Worker - Failed to send canonical {media_type} envelope to master: {e}")
-                debug_log(f"Worker - Full error details: URL={url}")
-                raise
+            await self._post_json_completion(session, url, payload)
 
     def _combine_audio(self, master_audio, worker_audio, empty_audio, worker_order=None):
         """Combine audio from master and workers into a single audio output.
@@ -319,12 +501,14 @@ class DistributedCollectorNode:
             return ensure_contiguous(fallback_images)
         return None
 
-    async def execute(self, images, audio, load_balance=False, multi_job_id="", is_worker=False, master_url="", enabled_worker_ids="[]", worker_batch_size=1, worker_id="", delegate_only=False):
+    async def execute(self, images, audio, load_balance=False, multi_job_id="", is_worker=False, master_url="", enabled_worker_ids="[]", worker_batch_size=1, worker_id="", delegate_only=False, transfer_format=transfer_codec.DEFAULT_TRANSFER_FORMAT, transfer_quality=transfer_codec.DEFAULT_TRANSFER_QUALITY):
         if is_worker:
             # Worker mode: send images and audio to master in a single batch
             image_count = 0 if images is None else images.shape[0]
             debug_log(f"Worker - Job {multi_job_id} complete. Sending {image_count} image(s) to master")
-            await self.send_batch_to_master(images, audio, multi_job_id, master_url, worker_id)
+            await self.send_batch_to_master(
+                images, audio, multi_job_id, master_url, worker_id, transfer_format, transfer_quality
+            )
             return (images, audio if audio is not None else self.EMPTY_AUDIO)
         else:
             delegate_mode = delegate_only or is_master_delegate_only()
@@ -339,6 +523,17 @@ class DistributedCollectorNode:
                 seen_enabled.add(worker_id_str)
                 enabled_workers.append(worker_id_str)
             expected_workers = set(enabled_workers)
+            serverless_workers = {
+                worker_id for worker_id in expected_workers if worker_id.startswith("serverless:")
+            }
+            serverless_manager = None
+
+            def get_serverless_manager():
+                nonlocal serverless_manager
+                if serverless_workers and serverless_manager is None:
+                    serverless_manager = self._get_serverless_manager()
+                return serverless_manager
+
             num_workers = len(expected_workers)
             if num_workers == 0:
                 return (images, audio if audio is not None else self.EMPTY_AUDIO)
@@ -405,152 +600,177 @@ class DistributedCollectorNode:
                 workers_done.add(done_worker_id)
                 p.update(1)  # +1 per completed expected worker
 
+            def consume_result(result):
+                nonlocal collected_count
+                if "serverless_error" in result:
+                    error = result.get("serverless_error")
+                    message = str(error).strip() if error is not None else "unspecified serverless failure"
+                    participant = result.get("worker_id", "unknown")
+                    raise RuntimeError(f"Serverless participant {participant} failed: {message}")
+
+                result_worker_id = str(result["worker_id"])
+                is_last = result.get("is_last", False)
+                collected_count += self._store_worker_result(worker_images, result)
+                debug_log(
+                    f"Master - Got canonical result from worker {result_worker_id}, "
+                    f"image {result.get('image_index', 0)}, is_last={is_last}"
+                )
+                result_audio = result.get("audio")
+                if result_audio is not None:
+                    worker_audio[result_worker_id] = result_audio
+                    debug_log(f"Master - Got audio from worker {result_worker_id}")
+                if is_last:
+                    mark_worker_done(result_worker_id)
+
             try:
                 while len(workers_done) < num_workers:
-                    # Check for user interruption to abort collection promptly
+                    # Check for user interruption to abort collection promptly.
                     comfy.model_management.throw_exception_if_processing_interrupted()
                     try:
-                        # Get the queue again each time to ensure we have the right reference
                         async with prompt_server.distributed_jobs_lock:
                             q = prompt_server.distributed_pending_jobs[multi_job_id]
-                            current_size = q.qsize()
-                        
                         result = await asyncio.wait_for(q.get(), timeout=slice_timeout)
-                        worker_id = result['worker_id']
-                        is_last = result.get('is_last', False)
-                        count = self._store_worker_result(worker_images, result)
-                        collected_count += count
-                        debug_log(
-                            f"Master - Got canonical result from worker {worker_id}, "
-                            f"image {result.get('image_index', 0)}, is_last={is_last}"
-                        )
+                        consume_result(result)
 
-                        # Collect audio data if present
-                        result_audio = result.get('audio')
-                        if result_audio is not None:
-                            worker_audio[worker_id] = result_audio
-                            debug_log(f"Master - Got audio from worker {worker_id}")
-
-                        # Record activity and refresh timeout baseline
+                        # Real results refresh the regular-worker timeout baseline.
                         last_activity = time.time()
                         base_timeout = float(get_worker_timeout_seconds())
 
-                        if is_last:
-                            mark_worker_done(worker_id)
-                        
                     except asyncio.TimeoutError:
-                        # If we still have time, continue polling; otherwise handle timeout
                         if (time.time() - last_activity) < base_timeout:
                             comfy.model_management.throw_exception_if_processing_interrupted()
                             continue
-                        # Re-check for user interruption after timeout expiry
                         comfy.model_management.throw_exception_if_processing_interrupted()
-                        missing_workers = set(str(w) for w in enabled_workers) - workers_done
+                        missing_workers = expected_workers - workers_done
+
+                        # A queue delivery can race the timed wait. Process it before
+                        # declaring an owned provider slot stopped without a result.
+                        async with prompt_server.distributed_jobs_lock:
+                            current_q = prompt_server.distributed_pending_jobs.get(multi_job_id)
+                            queue_has_results = current_q is not None and not current_q.empty()
+                        if queue_has_results:
+                            continue
+
+                        missing_serverless = missing_workers & serverless_workers
+                        if missing_serverless:
+                            manager = get_serverless_manager()
+                            if manager is None:
+                                raise RuntimeError("Serverless manager is unavailable for pending collector slots")
+                            pending_serverless = []
+                            for participant_id in sorted(missing_serverless):
+                                if manager.is_pending(multi_job_id, participant_id):
+                                    pending_serverless.append(participant_id)
+                                elif manager.owns(multi_job_id, participant_id):
+                                    raise RuntimeError(
+                                        f"Serverless participant {participant_id} stopped without delivering a result"
+                                    )
+                            # Provider deadlines are managed by the serverless runtime;
+                            # do not apply the regular worker heartbeat timeout to it.
+                            if pending_serverless:
+                                continue
+
+                        missing_regular = missing_workers - serverless_workers
                         elapsed = time.time() - last_activity
-                        for missing_worker_id in sorted(missing_workers):
+                        for missing_worker_id in sorted(missing_regular):
                             log(
                                 "Master - Heartbeat timeout: "
                                 f"worker={missing_worker_id}, elapsed={elapsed:.1f}s"
                             )
-                        log(
-                            f"Master - Heartbeat timeout. Still waiting for workers: {list(missing_workers)} "
-                            f"(elapsed={elapsed:.1f}s)"
-                        )
+                        if missing_regular:
+                            log(
+                                f"Master - Heartbeat timeout. Still waiting for workers: {list(sorted(missing_regular))} "
+                                f"(elapsed={elapsed:.1f}s)"
+                            )
 
-                        # Probe missing workers' /prompt endpoints to check if they are actively processing
+                        # Probe only regular worker /prompt endpoints.
                         any_busy = False
-                        try:
-                            cfg = load_config()
-                            cfg_workers = cfg.get('workers', [])
-                            for wid in list(missing_workers):
-                                wrec = next((w for w in cfg_workers if str(w.get('id')) == str(wid)), None)
-                                if not wrec:
-                                    debug_log(f"Collector probe: worker {wid} not found in config")
-                                    continue
-                                worker_url = build_worker_url(wrec)
-                                try:
-                                    payload = await probe_worker(worker_url, timeout=2.0)
-                                    queue_remaining = None
-                                    if payload is not None:
-                                        queue_remaining = int(payload.get('exec_info', {}).get('queue_remaining', 0))
-                                    debug_log(
-                                        "Collector probe: worker "
-                                        f"{wid} online={payload is not None} queue_remaining={queue_remaining}"
-                                    )
-                                    if payload is not None and queue_remaining and queue_remaining > 0:
-                                        any_busy = True
-                                        log(
-                                            f"Master - Probe grace: worker {wid} appears busy "
-                                            f"(queue_remaining={queue_remaining}). Continuing to wait."
+                        if missing_regular:
+                            try:
+                                cfg = load_config()
+                                cfg_workers = cfg.get('workers', [])
+                                for wid in sorted(missing_regular):
+                                    wrec = next((w for w in cfg_workers if str(w.get('id')) == str(wid)), None)
+                                    if not wrec:
+                                        debug_log(f"Collector probe: worker {wid} not found in config")
+                                        continue
+                                    worker_url = build_worker_url(wrec)
+                                    try:
+                                        payload = await probe_worker(worker_url, timeout=2.0)
+                                        queue_remaining = None
+                                        if payload is not None:
+                                            queue_remaining = int(payload.get('exec_info', {}).get('queue_remaining', 0))
+                                        debug_log(
+                                            "Collector probe: worker "
+                                            f"{wid} online={payload is not None} queue_remaining={queue_remaining}"
                                         )
-                                        break
-                                except Exception as e:
-                                    debug_log(f"Collector probe failed for worker {wid}: {e}")
-                        except Exception as e:
-                            debug_log(f"Collector probe setup error: {e}")
+                                        if payload is not None and queue_remaining and queue_remaining > 0:
+                                            any_busy = True
+                                            log(
+                                                f"Master - Probe grace: worker {wid} appears busy "
+                                                f"(queue_remaining={queue_remaining}). Continuing to wait."
+                                            )
+                                            break
+                                    except Exception as e:
+                                        debug_log(f"Collector probe failed for worker {wid}: {e}")
+                            except Exception as e:
+                                debug_log(f"Collector probe setup error: {e}")
 
                         if any_busy:
-                            # Refresh last_activity and continue waiting
                             last_activity = time.time()
-                            # Refresh base timeout in case the user changed it in UI
                             base_timeout = float(get_worker_timeout_seconds())
                             continue
-                        
-                        # Check queue size again with lock
+
                         async with prompt_server.distributed_jobs_lock:
-                            if multi_job_id in prompt_server.distributed_pending_jobs:
-                                final_q = prompt_server.distributed_pending_jobs[multi_job_id]
-                                final_size = final_q.qsize()
-                                
-                                # Try to drain any remaining items
-                                remaining_items = []
+                            final_q = prompt_server.distributed_pending_jobs.get(multi_job_id)
+                            remaining_items = []
+                            if final_q is not None:
                                 while not final_q.empty():
                                     try:
-                                        item = final_q.get_nowait()
-                                        remaining_items.append(item)
+                                        remaining_items.append(final_q.get_nowait())
                                     except asyncio.QueueEmpty:
                                         break
-                                
-                                if remaining_items:
-                                    # Process them
-                                    for item in remaining_items:
-                                        worker_id = item['worker_id']
-                                        is_last = item.get('is_last', False)
-
-                                        collected_count += self._store_worker_result(worker_images, item)
-                                        
-                                        if is_last:
-                                            mark_worker_done(worker_id)
-                            else:
-                                log(f"Master - Queue {multi_job_id} no longer exists!")
+                        for item in remaining_items:
+                            consume_result(item)
                         break
-            except comfy.model_management.InterruptProcessingException:
-                # Cleanup queue on interruption and re-raise to abort prompt cleanly
+
+                total_collected = sum(len(imgs) for imgs in worker_images.values())
+
+                # Remove the queue before combining so a late provider callback cannot
+                # resurrect results for a collector that has completed.
                 async with prompt_server.distributed_jobs_lock:
-                    if multi_job_id in prompt_server.distributed_pending_jobs:
-                        del prompt_server.distributed_pending_jobs[multi_job_id]
+                    prompt_server.distributed_pending_jobs.pop(multi_job_id, None)
+
+                combined_audio = self._combine_audio(master_audio, worker_audio, self.EMPTY_AUDIO, enabled_workers)
+                serverless_results = set(worker_images) & serverless_workers
+                try:
+                    combined = self._reorder_and_combine_tensors(
+                        worker_images, enabled_workers, master_batch_size, images_on_cpu, delegate_mode, images
+                    )
+                    if combined is None:
+                        debug_log(f"Master - Job {multi_job_id} complete with audio only")
+                    else:
+                        debug_log(f"Master - Job {multi_job_id} complete. Combined {combined.shape[0]} images total "
+                                  f"(master: {master_batch_size}, workers: {combined.shape[0] - master_batch_size})")
+                    return (combined, combined_audio)
+                except Exception as e:
+                    if serverless_results:
+                        raise RuntimeError(
+                            "Serverless result batch shape mismatch while combining participants "
+                            f"{sorted(serverless_results)}: {e}"
+                        ) from e
+                    log(f"Master - Error combining images: {e}")
+                    # Preserve collected audio for regular workers when image assembly fails.
+                    return (images, combined_audio)
+            except BaseException:
+                # Remove the queue first, preventing cancelled work from delivering into
+                # a collector that is already unwinding.
+                async with prompt_server.distributed_jobs_lock:
+                    prompt_server.distributed_pending_jobs.pop(multi_job_id, None)
+                if serverless_workers:
+                    try:
+                        manager = get_serverless_manager()
+                        if manager is not None:
+                            await manager.cancel(collector_job_id=multi_job_id)
+                    except Exception as cancel_error:
+                        debug_log(f"Collector - Serverless cancellation failed: {cancel_error}")
                 raise
-            
-            total_collected = sum(len(imgs) for imgs in worker_images.values())
-            
-            # Clean up job queue
-            async with prompt_server.distributed_jobs_lock:
-                if multi_job_id in prompt_server.distributed_pending_jobs:
-                    del prompt_server.distributed_pending_jobs[multi_job_id]
-
-            combined_audio = self._combine_audio(master_audio, worker_audio, self.EMPTY_AUDIO, enabled_workers)
-            try:
-                combined = self._reorder_and_combine_tensors(
-                    worker_images, enabled_workers, master_batch_size, images_on_cpu, delegate_mode, images
-                )
-                if combined is None:
-                    debug_log(f"Master - Job {multi_job_id} complete with audio only")
-                else:
-                    debug_log(f"Master - Job {multi_job_id} complete. Combined {combined.shape[0]} images total "
-                              f"(master: {master_batch_size}, workers: {combined.shape[0] - master_batch_size})")
-
-                return (combined, combined_audio)
-            except Exception as e:
-                log(f"Master - Error combining images: {e}")
-                # Preserve collected audio even when image assembly fails.
-                return (images, combined_audio)

nodes/distributed_upscale.py

@@ -268,12 +268,3 @@ class UltimateSDUpscaleDistributed(
 
 # Ensure initialization before registering routes
 ensure_tile_jobs_initialized()
-
-# Node registration
-NODE_CLASS_MAPPINGS = {
-    "UltimateSDUpscaleDistributed": UltimateSDUpscaleDistributed,
-}
-
-NODE_DISPLAY_NAME_MAPPINGS = {
-    "UltimateSDUpscaleDistributed": "Ultimate SD Upscale Distributed (No Upscale)",
-}

nodes/v3.py

@@ -0,0 +1,214 @@
+"""Native V3 schemas with the existing execution algorithms kept intact.
+
+Runtime objects are private, per-execution helpers, not registered V1 nodes.
+This avoids sharing mutable instance state through V3's sanitized class clones.
+"""
+import comfy.samplers
+from comfy_api.v0_0_2 import io
+
+from . import utilities as _utilities
+from .collector import DistributedCollectorNode as _CollectorRuntime
+from ..utils import transfer_codec as _transfer_codec
+from .distributed_upscale import UltimateSDUpscaleDistributed as _UpscaleRuntime
+
+
+class DistributedSeed(io.ComfyNode):
+    @classmethod
+    def define_schema(cls):
+        return io.Schema(
+            node_id='DistributedSeed', display_name='Distributed Seed', category='utils',
+            inputs=[io.Int.Input('seed', default=1125899906842, min=0,
+                                 max=1125899906842624, force_input=False)],
+            outputs=[io.Int.Output(display_name='seed')],
+            accept_all_inputs=True,
+        )
+
+    @classmethod
+    def execute(cls, seed, is_worker=False, worker_id=''):
+        return io.NodeOutput(*_utilities.DistributedSeed().distribute(seed, is_worker, worker_id))
+
+
+class DistributedValue(io.ComfyNode):
+    @classmethod
+    def define_schema(cls):
+        return io.Schema(
+            node_id='DistributedValue', display_name='Distributed Value', category='utils',
+            inputs=[io.String.Input('default_value', default=''),
+                    io.String.Input('worker_values', default='{}')],
+            outputs=[io.AnyType.Output(display_name='value')],
+            accept_all_inputs=True,
+        )
+
+    @classmethod
+    def execute(cls, default_value, worker_values='{}', is_worker=False, worker_id=''):
+        return io.NodeOutput(*_utilities.DistributedValue().distribute(
+            default_value, worker_values, is_worker, worker_id))
+
+
+class DistributedModelName(io.ComfyNode):
+    @classmethod
+    def define_schema(cls):
+        return io.Schema(
+            node_id='DistributedModelName', display_name='Distributed Model Name', category='utils',
+            inputs=[io.String.Input('text', default='')],
+            outputs=[io.AnyType.Output(display_name='output')],
+            hidden=[io.Hidden.unique_id, io.Hidden.extra_pnginfo], is_output_node=True,
+        )
+
+    @classmethod
+    def execute(cls, text):
+        result = _utilities.DistributedModelName().log_input(
+            text, unique_id=cls.hidden.unique_id, extra_pnginfo=cls.hidden.extra_pnginfo)
+        return io.NodeOutput(*result['result'], ui=result['ui'])
+
+
+class ImageBatchDivider(io.ComfyNode):
+    @classmethod
+    def define_schema(cls):
+        return io.Schema(
+            node_id='ImageBatchDivider', display_name='Image Batch Divider', category='image',
+            inputs=[io.Image.Input('images'),
+                    io.Int.Input('divide_by', default=2, min=1, max=10, step=1,
+                                 display_mode=io.NumberDisplay.number,
+                                 tooltip='Number of parts to divide the batch into')],
+            # The existing frontend still displays only divide_by sockets.
+            outputs=[io.Image.Output(display_name=f'batch_{index + 1}') for index in range(10)],
+            is_output_node=True,
+        )
+
+    @classmethod
+    def execute(cls, images, divide_by):
+        return io.NodeOutput(*_utilities.ImageBatchDivider().divide_batch(images, divide_by))
+
+
+class AudioBatchDivider(io.ComfyNode):
+    @classmethod
+    def define_schema(cls):
+        return io.Schema(
+            node_id='AudioBatchDivider', display_name='Audio Segment Divider', category='audio',
+            inputs=[io.Audio.Input('audio'),
+                    io.Int.Input('divide_by', default=2, min=1, max=10, step=1,
+                                 display_mode=io.NumberDisplay.number,
+                                 tooltip='Number of sequential time segments to create')],
+            outputs=[io.Audio.Output(display_name=f'audio_{index + 1}') for index in range(10)],
+            is_output_node=True,
+        )
+
+    @classmethod
+    def execute(cls, audio, divide_by):
+        return io.NodeOutput(*_utilities.AudioBatchDivider().divide_audio(audio, divide_by))
+
+
+class DistributedEmptyImage(io.ComfyNode):
+    @classmethod
+    def define_schema(cls):
+        return io.Schema(
+            node_id='DistributedEmptyImage', display_name='Distributed Empty Image', category='image',
+            inputs=[io.Int.Input('height', default=64, min=1, max=4096, step=1),
+                    io.Int.Input('width', default=64, min=1, max=4096, step=1),
+                    io.Int.Input('channels', default=3, min=1, max=4, step=1)],
+            outputs=[io.Image.Output()],
+        )
+
+    @classmethod
+    def execute(cls, height, width, channels):
+        return io.NodeOutput(*_utilities.DistributedEmptyImage().create(height, width, channels))
+
+
+class DistributedCollector(io.ComfyNode):
+    @classmethod
+    def define_schema(cls):
+        return io.Schema(
+            node_id='DistributedCollector', display_name='Distributed Collector', category='image',
+            inputs=[io.Boolean.Input('load_balance', default=False,
+                                     tooltip='Run this workflow on one least-busy participant (master included when participating).'),
+                    io.Image.Input('images', optional=True), io.Audio.Input('audio', optional=True),
+                    io.Combo.Input('transfer_format', options=list(_transfer_codec.TRANSFER_FORMATS),
+                                   default=_transfer_codec.DEFAULT_TRANSFER_FORMAT, optional=True,
+                                   tooltip=_transfer_codec.TRANSFER_FORMAT_TOOLTIP),
+                    io.Int.Input('transfer_quality', default=_transfer_codec.DEFAULT_TRANSFER_QUALITY,
+                                 min=1, max=100, step=1, optional=True,
+                                 tooltip=_transfer_codec.TRANSFER_QUALITY_TOOLTIP)],
+            outputs=[io.Image.Output(display_name='images'), io.Audio.Output(display_name='audio')],
+            is_input_list=True, accept_all_inputs=True,
+        )
+
+    @classmethod
+    def execute(cls, images=None, load_balance=False, audio=None, multi_job_id='',
+                is_worker=False, master_url='', enabled_worker_ids='[]', worker_batch_size=1,
+                worker_id='', pass_through=False, delegate_only=False,
+                transfer_format=_transfer_codec.DEFAULT_TRANSFER_FORMAT,
+                transfer_quality=_transfer_codec.DEFAULT_TRANSFER_QUALITY):
+        return io.NodeOutput(*_CollectorRuntime().run(
+            images=images, load_balance=load_balance, audio=audio, multi_job_id=multi_job_id,
+            is_worker=is_worker, master_url=master_url, enabled_worker_ids=enabled_worker_ids,
+            worker_batch_size=worker_batch_size, worker_id=worker_id,
+            pass_through=pass_through, delegate_only=delegate_only,
+            transfer_format=transfer_format, transfer_quality=transfer_quality))
+
+
+class UltimateSDUpscaleDistributed(io.ComfyNode):
+    @classmethod
+    def define_schema(cls):
+        return io.Schema(
+            node_id='UltimateSDUpscaleDistributed',
+            display_name='Ultimate SD Upscale Distributed (No Upscale)', category='image/upscaling',
+            inputs=[
+                io.Image.Input('upscaled_image'), io.Model.Input('model'),
+                io.Conditioning.Input('positive'), io.Conditioning.Input('negative'), io.Vae.Input('vae'),
+                io.Int.Input('seed', default=0, min=0, max=0xffffffffffffffff),
+                io.Int.Input('steps', default=20, min=1, max=10000),
+                io.Float.Input('cfg', default=8.0, min=0.0, max=100.0),
+                io.Combo.Input('sampler_name', options=comfy.samplers.KSampler.SAMPLERS),
+                io.Combo.Input('scheduler', options=comfy.samplers.KSampler.SCHEDULERS),
+                io.Float.Input('denoise', default=0.5, min=0.0, max=1.0, step=0.01),
+                io.Int.Input('tile_width', default=512, min=64, max=2048, step=8),
+                io.Int.Input('tile_height', default=512, min=64, max=2048, step=8),
+                io.Int.Input('padding', default=32, min=0, max=256, step=8),
+                io.Int.Input('mask_blur', default=8, min=0, max=256),
+                io.Boolean.Input('force_uniform_tiles', default=True),
+                io.Boolean.Input('tiled_decode', default=False),
+            ], outputs=[io.Image.Output()], accept_all_inputs=True,
+        )
+
+    @classmethod
+    def fingerprint_inputs(cls, **kwargs):
+        return _UpscaleRuntime.IS_CHANGED(**kwargs)
+
+    @classmethod
+    def execute(cls, upscaled_image, model, positive, negative, vae, seed, steps, cfg,
+                sampler_name, scheduler, denoise, tile_width, tile_height, padding,
+                mask_blur, force_uniform_tiles, tiled_decode, multi_job_id='', is_worker=False,
+                master_url='', enabled_worker_ids='[]', worker_id='', tile_indices='', dynamic_threshold=8):
+        return io.NodeOutput(*_UpscaleRuntime().run(
+            upscaled_image, model, positive, negative, vae, seed, steps, cfg,
+            sampler_name, scheduler, denoise, tile_width, tile_height, padding,
+            mask_blur, force_uniform_tiles, tiled_decode, multi_job_id, is_worker,
+            master_url, enabled_worker_ids, worker_id, tile_indices, dynamic_threshold))
+
+
+class DistributedWorkerSink(io.ComfyNode):
+    """Internal output node that terminates pruned worker prompts.
+
+    Worker prompts drop everything downstream of the distributed node, which
+    leaves no output node for ComfyUI to execute towards. This sink provides
+    one without writing preview files (PreviewImage wrote every frame to the
+    worker's temp directory). Hidden from search/menus; inserted by the master.
+    """
+
+    @classmethod
+    def define_schema(cls):
+        return io.Schema(
+            node_id='DistributedWorkerSink', display_name='Distributed Worker Sink (internal)', category='utils',
+            inputs=[io.AnyType.Input('value')],
+            is_output_node=True, is_dev_only=True,
+        )
+
+    @classmethod
+    def execute(cls, value):
+        return io.NodeOutput()
+
+
+NODES = [DistributedCollector, DistributedSeed, DistributedModelName, DistributedValue,
+         ImageBatchDivider, AudioBatchDivider, DistributedEmptyImage, UltimateSDUpscaleDistributed,
+         DistributedWorkerSink]

pyproject.toml

@@ -1,7 +1,7 @@
 [project]
 name = "ComfyUI-Distributed"
 description = "ComfyUI extension that enables multi-GPU processing locally, remotely and in the cloud"
-version = "1.4.7"
+version = "1.5.0"
 license = {file = "LICENSE"}
 dependencies  = []
 

runtime/__init__.py

@@ -0,0 +1 @@
+"""Internal extension lifecycle support (not a node provider)."""

runtime/bootstrap.py

@@ -0,0 +1,35 @@
+"""Initialize routes, distributed state and the existing worker lifecycle."""
+import atexit
+import os
+
+import server
+
+from ..utils.config import CONFIG_FILE, ensure_config_exists
+from ..utils.logging import debug_log
+from ..workers.startup import delayed_auto_launch, register_async_signals, sync_cleanup
+from ..upscale.job_store import ensure_tile_jobs_initialized
+
+_initialized = False
+
+
+def initialize():
+    """Called by ComfyExtension.on_load; initialize once per loaded package."""
+    global _initialized
+    if _initialized:
+        return
+
+    ensure_config_exists()
+    from .. import api  # noqa: F401 - registers the existing @routes.* handlers
+    from ..api.queue_orchestration import ensure_distributed_state
+
+    ensure_distributed_state(server.PromptServer.instance)
+    ensure_tile_jobs_initialized()
+
+    if not os.environ.get('COMFYUI_IS_WORKER'):
+        atexit.register(sync_cleanup)
+        delayed_auto_launch()
+        register_async_signals()
+
+    _initialized = True
+    debug_log('Loaded Distributed nodes.')
+    debug_log(f'Config file: {CONFIG_FILE}')

tests/api/test_config_routes.py

@@ -38,17 +38,10 @@ def _load_config_routes_module():
     sys.modules[f"{package_name}.api"] = api_pkg
 
     utils_pkg = types.ModuleType(f"{package_name}.utils")
-    utils_pkg.__path__ = []
+    utils_pkg.__path__ = [str(module_path.parents[1] / "utils")]
     sys.modules[f"{package_name}.utils"] = utils_pkg
 
-    created_aiohttp_stub = False
-    if "aiohttp" not in sys.modules:
-        created_aiohttp_stub = True
-        aiohttp_module = types.ModuleType("aiohttp")
-        aiohttp_module.web = types.SimpleNamespace(
-            json_response=lambda payload, status=200: _FakeResponse(payload, status=status)
-        )
-        sys.modules["aiohttp"] = aiohttp_module
+    import aiohttp  # Load the real dependency; isolate the fake response at the tested module.
 
     class _Routes:
         def get(self, _path):
@@ -96,8 +89,14 @@ def _load_config_routes_module():
     assert spec is not None and spec.loader is not None
     spec.loader.exec_module(module)
 
-    if created_aiohttp_stub:
-        sys.modules.pop("aiohttp", None)
+    class _EmptySecretStore:
+        def has(self, _worker_id):
+            return False
+
+    module.web = types.SimpleNamespace(
+        json_response=lambda payload, status=200: _FakeResponse(payload, status=status)
+    )
+    module._serverless_secret_store = lambda: _EmptySecretStore()
 
     return module
 

tests/api/test_distributed_queue.py

@@ -4,6 +4,8 @@ import types
 import unittest
 import asyncio
 import base64
+import io
+import json
 from dataclasses import dataclass
 from pathlib import Path
 from unittest.mock import AsyncMock, patch
@@ -26,6 +28,17 @@ class _FakeRequest:
         return self._payload
 
 
+def _register_real_transfer_codec(package_name, utils_pkg):
+    """Load the real utils/transfer_codec.py into the synthetic test package."""
+    codec_path = Path(__file__).resolve().parents[2] / "utils" / "transfer_codec.py"
+    codec_spec = importlib.util.spec_from_file_location(f"{package_name}.utils.transfer_codec", codec_path)
+    codec_module = importlib.util.module_from_spec(codec_spec)
+    sys.modules[f"{package_name}.utils.transfer_codec"] = codec_module
+    codec_spec.loader.exec_module(codec_module)
+    utils_pkg.transfer_codec = codec_module
+    return codec_module
+
+
 def _load_job_routes_module():
     module_path = Path(__file__).resolve().parents[2] / "api" / "job_routes.py"
     package_name = "dist_api_queue_testpkg"
@@ -46,6 +59,7 @@ def _load_job_routes_module():
     utils_pkg = types.ModuleType(f"{package_name}.utils")
     utils_pkg.__path__ = []
     sys.modules[f"{package_name}.utils"] = utils_pkg
+    _register_real_transfer_codec(package_name, utils_pkg)
 
     # aiohttp.web stub
     created_aiohttp_stub = False
@@ -205,6 +219,10 @@ def _load_job_routes_module():
     module = importlib.util.module_from_spec(spec)
     assert spec is not None and spec.loader is not None
     spec.loader.exec_module(module)
+    # Keep response assertions independent of real aiohttp import ordering.
+    module.web = types.SimpleNamespace(
+        json_response=lambda payload, status=200: _FakeResponse(payload, status=status)
+    )
 
     if created_aiohttp_stub:
         sys.modules.pop("aiohttp", None)
@@ -394,5 +412,144 @@ class JobCompleteAudioPayloadTests(unittest.IsolatedAsyncioTestCase):
             job_routes._decode_audio_payload(payload)
 
 
+class _FakeFileField:
+    def __init__(self, data):
+        self.file = io.BytesIO(data)
+
+
+class _FakeMultipartRequest:
+    content_type = "multipart/form-data"
+
+    def __init__(self, envelope, parts):
+        from multidict import MultiDict
+
+        fields = [("envelope", envelope if isinstance(envelope, str) else json.dumps(envelope))]
+        fields += [("media", _FakeFileField(part)) for part in parts]
+        self._form = MultiDict(fields)
+
+    async def post(self):
+        return self._form
+
+    async def json(self):
+        raise ValueError("not JSON")
+
+
+class JobCompleteCompressedPayloadTests(unittest.IsolatedAsyncioTestCase):
+    codec = job_routes.transfer_codec
+
+    def setUp(self):
+        self.queue = asyncio.Queue()
+        job_routes.prompt_server.distributed_jobs_lock = asyncio.Lock()
+        job_routes.prompt_server.distributed_pending_jobs = {"job-z": self.queue}
+
+    def _frames(self, count=4, height=20, width=30):
+        rng = np.random.default_rng(1)
+        return rng.integers(0, 256, (count, height, width, 3), dtype=np.uint8)
+
+    def _request_for(self, frames, fmt, *, start_offset=0, is_last=True, audio=None, **overrides):
+        chunk = next(self.codec.encode_chunks(frames, fmt, 90, 10**9))
+        parts = chunk.pop("parts")
+        envelope = {
+            "job_id": "job-z",
+            "worker_id": "worker-1",
+            "is_last": is_last,
+            **chunk,
+            "start_index": chunk["start_index"] + start_offset,
+        }
+        if audio is not None:
+            envelope["audio"] = audio
+        envelope.update(overrides)
+        return _FakeMultipartRequest(envelope, parts)
+
+    async def _drain(self):
+        items = []
+        while not self.queue.empty():
+            items.append(await self.queue.get())
+        return items
+
+    async def test_lossless_chunk_enqueues_one_item_per_frame_bit_exact(self):
+        frames = self._frames()
+        response = await job_routes.job_complete_endpoint(self._request_for(frames, "ffv1", start_offset=10))
+
+        self.assertEqual(response.status, 200)
+        items = await self._drain()
+        self.assertEqual([item["image_index"] for item in items], [10, 11, 12, 13])
+        self.assertEqual([item["is_last"] for item in items], [False, False, False, True])
+        self.assertEqual({item["worker_id"] for item in items}, {"worker-1"})
+        for item, frame in zip(items, frames):
+            self.assertEqual(tuple(item["tensor"].shape), (1, 20, 30, 3))
+            self.assertEqual(item["tensor"].dtype, torch.float32)
+            expected = frame.astype(np.float32) / 255.0
+            self.assertTrue(np.array_equal(item["tensor"][0].numpy(), expected))
+
+    async def test_non_final_chunk_never_marks_worker_done(self):
+        response = await job_routes.job_complete_endpoint(
+            self._request_for(self._frames(count=2), "png", is_last=False)
+        )
+
+        self.assertEqual(response.status, 200)
+        self.assertFalse(any(item["is_last"] for item in await self._drain()))
+
+    async def test_audio_is_attached_only_to_final_frame(self):
+        audio = JobCompleteAudioPayloadTests._encoded_audio_payload(None)
+        response = await job_routes.job_complete_endpoint(
+            self._request_for(self._frames(count=3), "jpeg", audio=audio)
+        )
+
+        self.assertEqual(response.status, 200)
+        items = await self._drain()
+        self.assertEqual([item["audio"] is not None for item in items], [False, False, True])
+        self.assertEqual(tuple(items[-1]["audio"]["waveform"].shape), (1, 2, 4))
+
+    async def test_rejects_frame_count_mismatch(self):
+        response = await job_routes.job_complete_endpoint(
+            self._request_for(self._frames(count=2), "ffv1", count=5)
+        )
+
+        self.assertEqual(response.status, 400)
+        self.assertIn("frames", response.payload["message"])
+        self.assertTrue(self.queue.empty())
+
+    async def test_rejects_bad_envelope(self):
+        response = await job_routes.job_complete_endpoint(
+            self._request_for(self._frames(count=1), "png", format="gif", is_last="yes")
+        )
+
+        self.assertEqual(response.status, 400)
+        self.assertIn("format", response.payload["message"])
+        self.assertIn("is_last", response.payload["message"])
+
+    async def test_rejects_invalid_envelope_json(self):
+        response = await job_routes.job_complete_endpoint(_FakeMultipartRequest("{not json", [b"x"]))
+
+        self.assertEqual(response.status, 400)
+        self.assertIn("envelope", response.payload["message"])
+
+    async def test_unknown_job_returns_404(self):
+        job_routes.prompt_server.distributed_pending_jobs = {}
+        with patch.object(job_routes, "JOB_INIT_GRACE_PERIOD", 0.0):
+            response = await job_routes.job_complete_endpoint(self._request_for(self._frames(count=1), "png"))
+
+        self.assertEqual(response.status, 404)
+
+    async def test_legacy_json_payload_still_accepted(self):
+        request = _FakeRequest(
+            {
+                "job_id": "job-z",
+                "worker_id": "worker-1",
+                "batch_idx": 3,
+                "image": "data:image/png;base64,AAAA",
+                "is_last": True,
+            }
+        )
+        with patch.object(job_routes, "_decode_canonical_png_tensor", return_value="tensor-data"):
+            response = await job_routes.job_complete_endpoint(request)
+
+        self.assertEqual(response.status, 200)
+        items = await self._drain()
+        self.assertEqual(len(items), 1)
+        self.assertEqual((items[0]["image_index"], items[0]["tensor"]), (3, "tensor-data"))
+
+
 if __name__ == "__main__":
     unittest.main()

tests/api/test_media_sync.py

@@ -164,26 +164,11 @@ class ConvertPathsForPlatformTests(unittest.TestCase):
 # ---------------------------------------------------------------------------
 
 class FindMediaReferencesTests(unittest.TestCase):
-    def test_finds_image_input(self):
-        prompt = {"1": {"class_type": "LoadImage", "inputs": {"image": "photo.png"}}}
-        refs = ms._find_media_references(prompt)
-        self.assertIn("photo.png", refs)
-
-    def test_finds_video_input(self):
-        prompt = {"1": {"class_type": "LoadVideo", "inputs": {"video": "clip.mp4"}}}
-        refs = ms._find_media_references(prompt)
-        self.assertIn("clip.mp4", refs)
-
     def test_finds_file_input_for_load_video(self):
         prompt = {"1": {"class_type": "LoadVideo", "inputs": {"file": "1 - Copy.mp4"}}}
         refs = ms._find_media_references(prompt)
         self.assertIn("1 - Copy.mp4", refs)
 
-    def test_finds_audio_input(self):
-        prompt = {"1": {"class_type": "LoadAudio", "inputs": {"audio": "track.wav"}}}
-        refs = ms._find_media_references(prompt)
-        self.assertIn("track.wav", refs)
-
     def test_strips_annotation_suffix(self):
         prompt = {"1": {"class_type": "LoadImage", "inputs": {"image": "photo.jpg [abc123]"}}}
         refs = ms._find_media_references(prompt)
@@ -260,3 +245,70 @@ class RewritePromptMediaInputsTests(unittest.TestCase):
 
 if __name__ == "__main__":
     unittest.main()
+
+
+# ---------------------------------------------------------------------------
+# fetch_worker_has_node
+# ---------------------------------------------------------------------------
+
+class _FakeResponse:
+    def __init__(self, status, payload):
+        self.status = status
+        self._payload = payload
+
+    async def json(self):
+        if isinstance(self._payload, Exception):
+            raise self._payload
+        return self._payload
+
+    async def __aenter__(self):
+        return self
+
+    async def __aexit__(self, *exc):
+        return False
+
+
+class _FakeSession:
+    def __init__(self, response=None, error=None):
+        self.response = response
+        self.error = error
+        self.urls = []
+
+    def get(self, url, timeout=None):
+        self.urls.append(url)
+        if self.error:
+            raise self.error
+        return self.response
+
+
+class FetchWorkerHasNodeTests(unittest.TestCase):
+    def _probe(self, session):
+        import asyncio
+
+        async def _get_session():
+            return session
+
+        original = ms.get_client_session
+        ms.get_client_session = _get_session
+        try:
+            return asyncio.run(ms.fetch_worker_has_node({"id": "w1"}, "DistributedWorkerSink"))
+        finally:
+            ms.get_client_session = original
+
+    def test_registered_node_is_reported(self):
+        session = _FakeSession(_FakeResponse(200, {"DistributedWorkerSink": {"name": "DistributedWorkerSink"}}))
+        self.assertTrue(self._probe(session))
+        self.assertEqual(session.urls, ["http://localhost/object_info/DistributedWorkerSink"])
+
+    def test_unknown_node_returns_empty_object(self):
+        # ComfyUI answers 200 {} for classes that are not registered.
+        self.assertFalse(self._probe(_FakeSession(_FakeResponse(200, {}))))
+
+    def test_http_error_counts_as_missing(self):
+        self.assertFalse(self._probe(_FakeSession(_FakeResponse(404, None))))
+
+    def test_bad_json_counts_as_missing(self):
+        self.assertFalse(self._probe(_FakeSession(_FakeResponse(200, ValueError("bad json")))))
+
+    def test_connection_error_counts_as_missing(self):
+        self.assertFalse(self._probe(_FakeSession(error=OSError("unreachable"))))

tests/api/test_transfer_integration.py

@@ -0,0 +1,219 @@
+"""End-to-end: real worker send path -> real aiohttp server -> job_complete endpoint."""
+import asyncio
+import importlib.util
+import sys
+from pathlib import Path
+
+import numpy as np
+import pytest
+import torch
+
+_TESTS_DIR = Path(__file__).resolve().parents[1]
+
+
+def _load_from(path, name):
+    spec = importlib.util.spec_from_file_location(name, path)
+    module = importlib.util.module_from_spec(spec)
+    spec.loader.exec_module(module)
+    return module
+
+
+def _load_modules():
+    real_aiohttp = sys.modules["aiohttp"]  # imported inside the isolated test
+    queue_tests = _load_from(_TESTS_DIR / "api" / "test_distributed_queue.py", "dist_transfer_it_queue")
+    collector_tests = _load_from(_TESTS_DIR / "test_collector_list_inputs.py", "dist_transfer_it_collector")
+    job_routes = queue_tests._load_job_routes_module()
+    collector = collector_tests._load_collector_module()
+
+    # Error responses must be real HTTP responses here (the unit-test harness
+    # returns plain objects); mirror utils.network.handle_api_error.
+    from aiohttp import web
+
+    async def handle_api_error(_request, error, status=500):
+        if isinstance(error, list):
+            return web.json_response({"errors": [str(item) for item in error]}, status=status)
+        return web.json_response({"error": str(error)}, status=status)
+
+    job_routes.handle_api_error = handle_api_error
+    # The queue-test harness also fakes aiohttp.web for route modules; the
+    # endpoint must build real responses for the real server used here.
+    job_routes.web = web
+    # The collector harness stubs aiohttp; this test needs the real client.
+    sys.modules["aiohttp"] = real_aiohttp
+    collector.aiohttp = real_aiohttp
+    return job_routes, collector
+
+
+@pytest.fixture(autouse=True)
+def _isolate_sys_modules():
+    """The loaders below install stub modules (server, comfy, aiohttp...); undo that."""
+    saved = dict(sys.modules)
+    # Earlier test modules may have left a stub `aiohttp` behind; drop it so the
+    # real package is imported for this test (restored afterwards).
+    for name in [n for n in sys.modules if n == "aiohttp" or n.startswith("aiohttp.")]:
+        if getattr(sys.modules[name], "__file__", None) is None:
+            del sys.modules[name]
+    yield
+    sys.modules.clear()
+    sys.modules.update(saved)
+
+
+async def _run_transfer(job_routes, collector_module, images, fmt, *, client_max_size,
+                        request_limit, chunk_target, audio=None):
+    """Send `images` from a real worker node to the real completion route.
+
+    Returns (queued items, sizes of every request body the server received,
+    exception raised by the worker or None).
+    """
+    import aiohttp
+    from aiohttp import web
+
+    queue = asyncio.Queue()
+    job_routes.prompt_server.distributed_jobs_lock = asyncio.Lock()
+    job_routes.prompt_server.distributed_pending_jobs = {"job-it": queue}
+    body_sizes = []
+
+    @web.middleware
+    async def record_size(request, handler):
+        body_sizes.append(request.content_length)
+        return await handler(request)
+
+    app = web.Application(client_max_size=client_max_size, middlewares=[record_size])
+    app.router.add_post("/distributed/job_complete", job_routes.job_complete_endpoint)
+    runner = web.AppRunner(app)
+    await runner.setup()
+    site = web.TCPSite(runner, "127.0.0.1", 0)
+    await site.start()
+    port = site._server.sockets[0].getsockname()[1]
+
+    error = None
+    try:
+        async with aiohttp.ClientSession() as session:
+            async def _get_session():
+                return session
+
+            collector_module.get_client_session = _get_session
+            collector_module.TRANSFER_MAX_REQUEST_BYTES = request_limit
+            collector_module.TRANSFER_MAX_CHUNK_BYTES = chunk_target
+            node = collector_module.DistributedCollectorNode()
+            try:
+                await node.send_batch_to_master(
+                    images, audio, "job-it", f"http://127.0.0.1:{port}", "worker-1", fmt, 90
+                )
+            except Exception as exc:  # surfaced to the caller for assertions
+                error = exc
+    finally:
+        await runner.cleanup()
+
+    items = []
+    while not queue.empty():
+        items.append(queue.get_nowait())
+    return items, body_sizes, error
+
+
+def _noise_images(count, height=360, width=640, seed=97):
+    return torch.from_numpy(np.random.default_rng(seed).random((count, height, width, 3), dtype=np.float32))
+
+
+@pytest.mark.parametrize("fmt", ["h264", "ffv1"])
+def test_high_entropy_video_stays_under_server_upload_limit(fmt):
+    """Encoder flush used to push finalized chunks past the limit (HTTP 400)."""
+    pytest.importorskip("aiohttp")
+    job_routes, collector_module = _load_modules()
+    images = _noise_images(24)
+    limit = 2 * 1024 * 1024
+    reserve = collector_module.DistributedCollectorNode.TRANSFER_ENVELOPE_RESERVE_BYTES
+
+    items, body_sizes, error = asyncio.run(_run_transfer(
+        job_routes, collector_module, images, fmt,
+        client_max_size=limit, request_limit=limit, chunk_target=limit - reserve))
+
+    assert error is None, error
+    assert len(body_sizes) > 1 and max(body_sizes) <= limit
+    assert [item["image_index"] for item in items] == list(range(24))
+    assert [item["is_last"] for item in items] == [False] * 23 + [True]
+
+
+def test_server_rejection_for_size_is_reported_not_retried_as_legacy():
+    """A worker configured above the master's limit fails loudly instead of
+    silently resending the whole batch as uncompressed PNG."""
+    pytest.importorskip("aiohttp")
+    job_routes, collector_module = _load_modules()
+    images = _noise_images(8)
+
+    items, body_sizes, error = asyncio.run(_run_transfer(
+        job_routes, collector_module, images, "ffv1",
+        client_max_size=1024 * 1024, request_limit=8 * 1024 * 1024, chunk_target=4 * 1024 * 1024))
+
+    assert isinstance(error, RuntimeError)
+    assert "HTTP 413" in str(error) and "--max-upload-size" in str(error)
+    assert len(body_sizes) == 1
+    assert items == []
+
+
+def test_frame_that_cannot_fit_sends_nothing():
+    pytest.importorskip("aiohttp")
+    job_routes, collector_module = _load_modules()
+    images = _noise_images(3)
+    reserve = collector_module.DistributedCollectorNode.TRANSFER_ENVELOPE_RESERVE_BYTES
+
+    items, body_sizes, error = asyncio.run(_run_transfer(
+        job_routes, collector_module, images, "png",
+        client_max_size=100 * 1024 * 1024, request_limit=reserve + 64 * 1024, chunk_target=64 * 1024))
+
+    assert isinstance(error, collector_module.transfer_codec.FrameTooLargeError)
+    assert body_sizes == []
+    assert items == []
+
+
+@pytest.mark.parametrize("fmt", ["png", "ffv1", "h264", "jpeg"])
+def test_worker_to_master_over_real_http(fmt):
+    # Import here, not at module level: other test harnesses only install their
+    # aiohttp stubs when the real package has not been imported yet.
+    aiohttp = pytest.importorskip("aiohttp")
+    from aiohttp import web
+
+    job_routes, collector_module = _load_modules()
+    images = torch.rand(5, 24, 36, 3)
+
+    async def scenario():
+        queue = asyncio.Queue()
+        job_routes.prompt_server.distributed_jobs_lock = asyncio.Lock()
+        job_routes.prompt_server.distributed_pending_jobs = {"job-it": queue}
+
+        app = web.Application()
+        app.router.add_post("/distributed/job_complete", job_routes.job_complete_endpoint)
+        runner = web.AppRunner(app)
+        await runner.setup()
+        site = web.TCPSite(runner, "127.0.0.1", 0)
+        await site.start()
+        port = site._server.sockets[0].getsockname()[1]
+
+        async with aiohttp.ClientSession() as session:
+            async def _get_session():
+                return session
+
+            collector_module.get_client_session = _get_session
+            collector_module.TRANSFER_MAX_CHUNK_BYTES = 2000  # several requests for still formats
+            node = collector_module.DistributedCollectorNode()
+            await node.send_batch_to_master(
+                images, None, "job-it", f"http://127.0.0.1:{port}", "worker-1", fmt, 90
+            )
+        await runner.cleanup()
+
+        items = []
+        while not queue.empty():
+            items.append(queue.get_nowait())
+        return items
+
+    items = asyncio.run(scenario())
+
+    assert [item["image_index"] for item in items] == [0, 1, 2, 3, 4]
+    assert [item["is_last"] for item in items] == [False, False, False, False, True]
+    expected = np.clip(255.0 * images.numpy(), 0, 255).astype(np.uint8).astype(np.float32) / 255.0
+    got = torch.cat([item["tensor"] for item in items]).numpy()
+    assert got.shape == expected.shape
+    if fmt in ("png", "ffv1"):
+        assert np.array_equal(got, expected)
+    else:
+        assert np.abs(got - expected).mean() < 0.25  # random noise: only sanity-check lossy codecs

tests/api/test_worker_routes.py

@@ -106,7 +106,7 @@ def _load_worker_routes_module():
     sys.modules[f"{package_name}.utils"] = utils_pkg
 
     workers_pkg = types.ModuleType(f"{package_name}.workers")
-    workers_pkg.__path__ = []
+    workers_pkg.__path__ = [str(module_path.parents[1] / "workers")]
     workers_pkg.get_worker_manager = lambda: _DummyWorkerManager()
     sys.modules[f"{package_name}.workers"] = workers_pkg
 
@@ -213,6 +213,7 @@ def _load_worker_routes_module():
         raise RuntimeError("not used in these tests")
 
     network_module.get_client_session = _get_client_session
+    network_module.get_server_port = lambda: 8189
     sys.modules[f"{package_name}.utils.network"] = network_module
 
     constants_module = types.ModuleType(f"{package_name}.utils.constants")
@@ -256,6 +257,8 @@ def _load_worker_routes_module():
     module = importlib.util.module_from_spec(spec)
     assert spec is not None and spec.loader is not None
     spec.loader.exec_module(module)
+    # Keep this module's response double independent of aiohttp import order.
+    module.web = types.SimpleNamespace(json_response=lambda payload, status=200: _FakeResponse(payload, status))
 
     if created_aiohttp_stub:
         sys.modules.pop("aiohttp", None)
@@ -269,6 +272,38 @@ worker_routes = _load_worker_routes_module()
 
 
 class WorkerRoutesTests(unittest.IsolatedAsyncioTestCase):
+    async def test_network_info_reports_actual_master_and_available_ports(self):
+        with patch.object(worker_routes, "_get_cuda_info", return_value=(0, 1, 4)), \
+             patch.object(worker_routes, "get_network_ips", return_value=["127.0.0.1"]), \
+             patch.object(worker_routes, "load_config", return_value={"workers": []}), \
+             patch.object(worker_routes, "get_server_port", return_value=8189), \
+             patch.object(worker_routes, "allocate_worker_ports", return_value=[8191, 8192, 8193]) as allocate:
+            response = await worker_routes.get_network_info_endpoint(_FakeRequest())
+        self.assertEqual(response.payload["master_port"], 8189)
+        self.assertEqual(response.payload["local_worker_ports"], [8191, 8192, 8193])
+        self.assertEqual(response.payload["cuda_device_count"], 4)
+        allocate.assert_called_once_with(8189, [], 3)
+
+    async def test_network_info_does_not_reallocate_existing_configuration(self):
+        with patch.object(worker_routes, "_get_cuda_info", return_value=(0, 4, 4)), \
+             patch.object(worker_routes, "get_network_ips", return_value=[]), \
+             patch.object(worker_routes, "load_config", return_value={"workers": [{"id": "existing", "port": 8189}]}), \
+             patch.object(worker_routes, "allocate_worker_ports") as allocate:
+            response = await worker_routes.get_network_info_endpoint(_FakeRequest())
+        self.assertEqual(response.payload["local_worker_ports"], [])
+        allocate.assert_not_called()
+
+    async def test_launch_conflict_is_a_clear_client_error(self):
+        manager = _DummyWorkerManager()
+        config = {"workers": [{"id": "worker-a", "name": "Worker A", "port": 8189}]}
+        with patch.object(worker_routes, "get_worker_manager", return_value=manager), \
+             patch.object(worker_routes, "load_config", return_value=config), \
+             patch.object(manager, "launch_worker", side_effect=ValueError("Worker port 8189 conflicts with the master port 8189")):
+            response = await worker_routes.launch_worker_endpoint(_FakeRequest({"worker_id": "worker-a"}))
+        self.assertEqual(response.status, 400)
+        self.assertIn("master port 8189", response.payload["message"])
+        self.assertEqual(manager.processes, {})
+
     async def test_launch_worker_valid_id_returns_200(self):
         manager = _DummyWorkerManager()
         config = {"workers": [{"id": "worker-a", "name": "Worker A", "port": 8188}]}

tests/fixtures/v1_node_contracts.json

@@ -0,0 +1,691 @@
+{
+  "DistributedCollector": {
+    "input": {
+      "required": {
+        "load_balance": [
+          "BOOLEAN",
+          {
+            "default": false,
+            "tooltip": "Run this workflow on one least-busy participant (master included when participating)."
+          }
+        ]
+      },
+      "optional": {
+        "images": [
+          "IMAGE"
+        ],
+        "audio": [
+          "AUDIO"
+        ]
+      },
+      "hidden": {
+        "multi_job_id": [
+          "STRING",
+          {
+            "default": ""
+          }
+        ],
+        "is_worker": [
+          "BOOLEAN",
+          {
+            "default": false
+          }
+        ],
+        "master_url": [
+          "STRING",
+          {
+            "default": ""
+          }
+        ],
+        "enabled_worker_ids": [
+          "STRING",
+          {
+            "default": "[]"
+          }
+        ],
+        "worker_batch_size": [
+          "INT",
+          {
+            "default": 1,
+            "min": 1,
+            "max": 1024
+          }
+        ],
+        "worker_id": [
+          "STRING",
+          {
+            "default": ""
+          }
+        ],
+        "pass_through": [
+          "BOOLEAN",
+          {
+            "default": false
+          }
+        ],
+        "delegate_only": [
+          "BOOLEAN",
+          {
+            "default": false
+          }
+        ]
+      }
+    },
+    "input_order": {
+      "required": [
+        "load_balance"
+      ],
+      "optional": [
+        "images",
+        "audio"
+      ],
+      "hidden": [
+        "multi_job_id",
+        "is_worker",
+        "master_url",
+        "enabled_worker_ids",
+        "worker_batch_size",
+        "worker_id",
+        "pass_through",
+        "delegate_only"
+      ]
+    },
+    "output": [
+      "IMAGE",
+      "AUDIO"
+    ],
+    "output_name": [
+      "images",
+      "audio"
+    ],
+    "output_is_list": [
+      false,
+      false
+    ],
+    "is_input_list": true,
+    "output_node": false,
+    "category": "image",
+    "display_name": "Distributed Collector"
+  },
+  "DistributedSeed": {
+    "input": {
+      "required": {
+        "seed": [
+          "INT",
+          {
+            "default": 1125899906842,
+            "min": 0,
+            "max": 1125899906842624,
+            "forceInput": false
+          }
+        ]
+      },
+      "hidden": {
+        "is_worker": [
+          "BOOLEAN",
+          {
+            "default": false
+          }
+        ],
+        "worker_id": [
+          "STRING",
+          {
+            "default": ""
+          }
+        ]
+      }
+    },
+    "input_order": {
+      "required": [
+        "seed"
+      ],
+      "hidden": [
+        "is_worker",
+        "worker_id"
+      ]
+    },
+    "output": [
+      "INT"
+    ],
+    "output_name": [
+      "seed"
+    ],
+    "output_is_list": [
+      false
+    ],
+    "is_input_list": false,
+    "output_node": false,
+    "category": "utils",
+    "display_name": "Distributed Seed"
+  },
+  "DistributedModelName": {
+    "input": {
+      "required": {
+        "text": [
+          "STRING",
+          {
+            "default": ""
+          }
+        ]
+      },
+      "hidden": {
+        "unique_id": "UNIQUE_ID",
+        "extra_pnginfo": "EXTRA_PNGINFO"
+      }
+    },
+    "input_order": {
+      "required": [
+        "text"
+      ],
+      "hidden": [
+        "unique_id",
+        "extra_pnginfo"
+      ]
+    },
+    "output": [
+      "*"
+    ],
+    "output_name": [
+      "output"
+    ],
+    "output_is_list": [
+      false
+    ],
+    "is_input_list": false,
+    "output_node": true,
+    "category": "utils",
+    "display_name": "Distributed Model Name"
+  },
+  "DistributedValue": {
+    "input": {
+      "required": {
+        "default_value": [
+          "STRING",
+          {
+            "default": ""
+          }
+        ],
+        "worker_values": [
+          "STRING",
+          {
+            "default": "{}"
+          }
+        ]
+      },
+      "hidden": {
+        "is_worker": [
+          "BOOLEAN",
+          {
+            "default": false
+          }
+        ],
+        "worker_id": [
+          "STRING",
+          {
+            "default": ""
+          }
+        ]
+      }
+    },
+    "input_order": {
+      "required": [
+        "default_value",
+        "worker_values"
+      ],
+      "hidden": [
+        "is_worker",
+        "worker_id"
+      ]
+    },
+    "output": [
+      "*"
+    ],
+    "output_name": [
+      "value"
+    ],
+    "output_is_list": [
+      false
+    ],
+    "is_input_list": false,
+    "output_node": false,
+    "category": "utils",
+    "display_name": "Distributed Value"
+  },
+  "ImageBatchDivider": {
+    "input": {
+      "required": {
+        "images": [
+          "IMAGE"
+        ],
+        "divide_by": [
+          "INT",
+          {
+            "default": 2,
+            "min": 1,
+            "max": 10,
+            "step": 1,
+            "display": "number",
+            "tooltip": "Number of parts to divide the batch into"
+          }
+        ]
+      }
+    },
+    "input_order": {
+      "required": [
+        "images",
+        "divide_by"
+      ]
+    },
+    "output": [
+      "*",
+      "*",
+      "*",
+      "*",
+      "*",
+      "*",
+      "*",
+      "*",
+      "*",
+      "*"
+    ],
+    "output_name": [
+      "batch_1",
+      "batch_2",
+      "batch_3",
+      "batch_4",
+      "batch_5",
+      "batch_6",
+      "batch_7",
+      "batch_8",
+      "batch_9",
+      "batch_10"
+    ],
+    "output_is_list": [
+      false,
+      false,
+      false,
+      false,
+      false,
+      false,
+      false,
+      false,
+      false,
+      false
+    ],
+    "is_input_list": false,
+    "output_node": true,
+    "category": "image",
+    "display_name": "Image Batch Divider"
+  },
+  "AudioBatchDivider": {
+    "input": {
+      "required": {
+        "audio": [
+          "AUDIO"
+        ],
+        "divide_by": [
+          "INT",
+          {
+            "default": 2,
+            "min": 1,
+            "max": 10,
+            "step": 1,
+            "display": "number",
+            "tooltip": "Number of sequential time segments to create"
+          }
+        ]
+      }
+    },
+    "input_order": {
+      "required": [
+        "audio",
+        "divide_by"
+      ]
+    },
+    "output": [
+      "*",
+      "*",
+      "*",
+      "*",
+      "*",
+      "*",
+      "*",
+      "*",
+      "*",
+      "*"
+    ],
+    "output_name": [
+      "audio_1",
+      "audio_2",
+      "audio_3",
+      "audio_4",
+      "audio_5",
+      "audio_6",
+      "audio_7",
+      "audio_8",
+      "audio_9",
+      "audio_10"
+    ],
+    "output_is_list": [
+      false,
+      false,
+      false,
+      false,
+      false,
+      false,
+      false,
+      false,
+      false,
+      false
+    ],
+    "is_input_list": false,
+    "output_node": true,
+    "category": "audio",
+    "display_name": "Audio Segment Divider"
+  },
+  "DistributedEmptyImage": {
+    "input": {
+      "required": {
+        "height": [
+          "INT",
+          {
+            "default": 64,
+            "min": 1,
+            "max": 4096,
+            "step": 1
+          }
+        ],
+        "width": [
+          "INT",
+          {
+            "default": 64,
+            "min": 1,
+            "max": 4096,
+            "step": 1
+          }
+        ],
+        "channels": [
+          "INT",
+          {
+            "default": 3,
+            "min": 1,
+            "max": 4,
+            "step": 1
+          }
+        ]
+      }
+    },
+    "input_order": {
+      "required": [
+        "height",
+        "width",
+        "channels"
+      ]
+    },
+    "output": [
+      "IMAGE"
+    ],
+    "output_name": [
+      "IMAGE"
+    ],
+    "output_is_list": [
+      false
+    ],
+    "is_input_list": false,
+    "output_node": false,
+    "category": "image",
+    "display_name": "Distributed Empty Image"
+  },
+  "UltimateSDUpscaleDistributed": {
+    "input": {
+      "required": {
+        "upscaled_image": [
+          "IMAGE"
+        ],
+        "model": [
+          "MODEL"
+        ],
+        "positive": [
+          "CONDITIONING"
+        ],
+        "negative": [
+          "CONDITIONING"
+        ],
+        "vae": [
+          "VAE"
+        ],
+        "seed": [
+          "INT",
+          {
+            "default": 0,
+            "min": 0,
+            "max": 18446744073709551615
+          }
+        ],
+        "steps": [
+          "INT",
+          {
+            "default": 20,
+            "min": 1,
+            "max": 10000
+          }
+        ],
+        "cfg": [
+          "FLOAT",
+          {
+            "default": 8.0,
+            "min": 0.0,
+            "max": 100.0
+          }
+        ],
+        "sampler_name": [
+          [
+            "euler",
+            "euler_cfg_pp",
+            "euler_ancestral",
+            "euler_ancestral_cfg_pp",
+            "heun",
+            "heunpp2",
+            "exp_heun_2_x0",
+            "exp_heun_2_x0_sde",
+            "dpm_2",
+            "dpm_2_ancestral",
+            "lms",
+            "dpm_fast",
+            "dpm_adaptive",
+            "dpmpp_2s_ancestral",
+            "dpmpp_2s_ancestral_cfg_pp",
+            "dpmpp_sde",
+            "dpmpp_sde_gpu",
+            "dpmpp_2m",
+            "dpmpp_2m_cfg_pp",
+            "dpmpp_2m_sde",
+            "dpmpp_2m_sde_gpu",
+            "dpmpp_2m_sde_heun",
+            "dpmpp_2m_sde_heun_gpu",
+            "dpmpp_3m_sde",
+            "dpmpp_3m_sde_gpu",
+            "ddpm",
+            "lcm",
+            "ipndm",
+            "ipndm_v",
+            "deis",
+            "cfgpp_ud10_ab",
+            "res_multistep",
+            "res_multistep_cfg_pp",
+            "res_multistep_ancestral",
+            "res_multistep_ancestral_cfg_pp",
+            "gradient_estimation",
+            "gradient_estimation_cfg_pp",
+            "er_sde",
+            "seeds_2",
+            "seeds_3",
+            "sa_solver",
+            "sa_solver_pece",
+            "ddim",
+            "uni_pc",
+            "uni_pc_bh2"
+          ]
+        ],
+        "scheduler": [
+          [
+            "simple",
+            "sgm_uniform",
+            "karras",
+            "exponential",
+            "ddim_uniform",
+            "beta",
+            "normal",
+            "linear_quadratic",
+            "kl_optimal"
+          ]
+        ],
+        "denoise": [
+          "FLOAT",
+          {
+            "default": 0.5,
+            "min": 0.0,
+            "max": 1.0,
+            "step": 0.01
+          }
+        ],
+        "tile_width": [
+          "INT",
+          {
+            "default": 512,
+            "min": 64,
+            "max": 2048,
+            "step": 8
+          }
+        ],
+        "tile_height": [
+          "INT",
+          {
+            "default": 512,
+            "min": 64,
+            "max": 2048,
+            "step": 8
+          }
+        ],
+        "padding": [
+          "INT",
+          {
+            "default": 32,
+            "min": 0,
+            "max": 256,
+            "step": 8
+          }
+        ],
+        "mask_blur": [
+          "INT",
+          {
+            "default": 8,
+            "min": 0,
+            "max": 256
+          }
+        ],
+        "force_uniform_tiles": [
+          "BOOLEAN",
+          {
+            "default": true
+          }
+        ],
+        "tiled_decode": [
+          "BOOLEAN",
+          {
+            "default": false
+          }
+        ]
+      },
+      "hidden": {
+        "multi_job_id": [
+          "STRING",
+          {
+            "default": ""
+          }
+        ],
+        "is_worker": [
+          "BOOLEAN",
+          {
+            "default": false
+          }
+        ],
+        "master_url": [
+          "STRING",
+          {
+            "default": ""
+          }
+        ],
+        "enabled_worker_ids": [
+          "STRING",
+          {
+            "default": "[]"
+          }
+        ],
+        "worker_id": [
+          "STRING",
+          {
+            "default": ""
+          }
+        ],
+        "tile_indices": [
+          "STRING",
+          {
+            "default": ""
+          }
+        ],
+        "dynamic_threshold": [
+          "INT",
+          {
+            "default": 8,
+            "min": 1,
+            "max": 64
+          }
+        ]
+      }
+    },
+    "input_order": {
+      "required": [
+        "upscaled_image",
+        "model",
+        "positive",
+        "negative",
+        "vae",
+        "seed",
+        "steps",
+        "cfg",
+        "sampler_name",
+        "scheduler",
+        "denoise",
+        "tile_width",
+        "tile_height",
+        "padding",
+        "mask_blur",
+        "force_uniform_tiles",
+        "tiled_decode"
+      ],
+      "hidden": [
+        "multi_job_id",
+        "is_worker",
+        "master_url",
+        "enabled_worker_ids",
+        "worker_id",
+        "tile_indices",
+        "dynamic_threshold"
+      ]
+    },
+    "output": [
+      "IMAGE"
+    ],
+    "output_name": [
+      "IMAGE"
+    ],
+    "output_is_list": [
+      false
+    ],
+    "is_input_list": false,
+    "output_node": false,
+    "category": "image/upscaling",
+    "display_name": "Ultimate SD Upscale Distributed (No Upscale)"
+  }
+}

tests/helpers/v3_runtime_check.py

@@ -0,0 +1,324 @@
+"""Exercise the actual loader, schemas and executor in a fresh CPU process.
+
+No HTTP listener, workers, model downloads or live installation changes.
+The original contracts were captured from 32ac027 using the same core.
+"""
+import asyncio
+import inspect
+import json
+import os
+from pathlib import Path
+import sys
+import tempfile
+from unittest.mock import patch
+
+from PIL import Image
+
+ROOT = Path(__file__).resolve().parents[2]
+COMFY_ROOT = Path(sys.argv[1]).resolve()
+sys.path.insert(0, str(COMFY_ROOT))
+os.environ['COMFYUI_IS_WORKER'] = '1'
+import comfy.cli_args
+comfy.cli_args.args.cpu = True
+comfy.cli_args.args.disable_assets = True
+from app.assets.manager import default_asset_manager
+from comfy_api.v0_0_2 import io
+import execution
+import nodes
+import server
+import torch
+
+BASELINE = json.loads((ROOT / 'tests/fixtures/v1_node_contracts.json').read_text())
+
+# Inputs intentionally added after the V1 baseline was captured. They must be
+# optional, appended after the baseline inputs, and keep legacy behaviour as
+# their default so saved workflows are unaffected.
+ADDED_OPTIONAL_INPUTS = {
+    'DistributedCollector': {
+        'transfer_format': [
+            ['legacy_png', 'png', 'ffv1', 'jpeg', 'webp', 'h264', 'h265', 'av1'],
+            {'default': 'legacy_png'},
+        ],
+        'transfer_quality': ['INT', {'default': 90, 'min': 1, 'max': 100, 'step': 1}],
+    },
+}
+
+# Nodes added after the V1 baseline; not part of saved-workflow contracts.
+# DistributedWorkerSink is internal (dev-only) and only inserted by the master.
+ADDED_NODES = {'DistributedWorkerSink'}
+
+
+def normalized_input(value):
+    kind = value[0]
+    opts = dict(value[1]) if len(value) > 1 else {}
+    if kind == 'STRING':
+        # V3 serializes the same default single-line widget explicitly.
+        opts.setdefault('multiline', False)
+    if kind == 'COMBO':
+        kind = opts['options']
+        opts = {key: val for key, val in opts.items() if key != 'options'}
+    if isinstance(kind, list):
+        # Single-selection is the V1 dropdown default as well.
+        opts.setdefault('multiselect', False)
+    return [kind, opts]
+
+
+async def map_node(cls, values, extra=None):
+    """Use the actual input parser and sanitized V3 executor clones."""
+    prepared, missing, hidden = execution.get_input_data(values, cls, unique_id='probe', extra_data=extra or {})
+    assert not missing, missing
+    # Use a worker thread for synchronous nodes: collector/upscale bridge back
+    # to PromptServer's running loop, just as ComfyUI's prompt worker does.
+    def run():
+        return asyncio.run(execution._async_map_node_over_list(
+            'v3-acceptance', 'probe', cls, prepared, cls.FUNCTION, v3_data=hidden))
+    return await asyncio.to_thread(run)
+
+
+def check_saved_workflows(mapping):
+    checked = 0
+    occurrences = 0
+    for path in sorted((ROOT / 'workflows').glob('*.json')):
+        workflow = json.loads(path.read_text())
+        local_nodes = {node['id']: node for node in workflow['nodes']}
+        for saved in workflow['nodes']:
+            if saved['type'] not in mapping:
+                continue
+            occurrences += 1
+            info = mapping[saved['type']].GET_NODE_INFO_V1()
+            inputs = {**info['input'].get('required', {}), **info['input'].get('optional', {})}
+            for socket in saved.get('inputs', []):
+                assert socket['name'] in inputs, (path.name, saved['id'], socket)
+                assert socket['type'] == inputs[socket['name']][0], (path.name, socket)
+            for index, output in enumerate(saved.get('outputs', [])):
+                assert output['type'] == info['output'][index], (path.name, index)
+            for link in workflow['links']:
+                if link[1] == saved['id']:
+                    assert link[2] < len(info['output']), (path.name, link)
+                    target = local_nodes[link[3]]['inputs'][link[4]]
+                    assert target['type'] == info['output'][link[2]], (path.name, link)
+        checked += 1
+    assert checked == 5 and occurrences == 10, (checked, occurrences)
+    print('SAVED_WORKFLOW_CONTRACTS_OK', checked, occurrences)
+
+
+async def check_execution(mapping, module, prompt_server, asset_manager):
+    result = await map_node(mapping['DistributedSeed'],
+                            {'seed': 123, 'is_worker': True, 'worker_id': 'worker_2'})
+    assert result[0].result == (126,)
+    values = json.dumps({'_type': 'INT', '3': '17'})
+    result = await map_node(mapping['DistributedValue'],
+                            {'default_value': '4', 'worker_values': values,
+                             'is_worker': True, 'worker_id': 'worker_2'})
+    assert result[0].result == (17,)
+    metadata = {'workflow': {'nodes': [{'id': 'probe', 'widgets_values': []}]}}
+    result = await map_node(mapping['DistributedModelName'], {'text': 'model.ckpt'},
+                            {'extra_pnginfo': metadata})
+    assert result[0].result == ('model.ckpt',)
+    assert result[0].ui == {'text': ['model.ckpt']}
+    assert metadata['workflow']['nodes'][0]['widgets_values'] == [['model.ckpt']]
+    result = await map_node(mapping['DistributedEmptyImage'],
+                            {'height': 8, 'width': 8, 'channels': 3})
+    empty = result[0].result[0]
+    assert empty.shape == (0, 8, 8, 3) and empty.numel() == 0
+    images = torch.arange(10 * 8 * 8 * 3, dtype=torch.float32).reshape(10, 8, 8, 3)
+    for count in (1, 3, 10):
+        result = await map_node(mapping['ImageBatchDivider'], {'images': images, 'divide_by': count})
+        assert len(result[0].result) == 10
+        assert torch.equal(torch.cat(result[0].result[:count]), images)
+    audio = {'waveform': torch.arange(33, dtype=torch.float32).reshape(1, 1, 33), 'sample_rate': 24000}
+    result = await map_node(mapping['AudioBatchDivider'], {'audio': audio, 'divide_by': 3})
+    assert len(result[0].result) == 10
+    assert torch.equal(torch.cat([item['waveform'] for item in result[0].result[:3]], dim=-1), audio['waveform'])
+    # INPUT_IS_LIST must preserve all images/audio but unwrap transport scalars.
+    collector = mapping['DistributedCollector']
+    prepared, missing, hidden = execution.get_input_data(
+        {'load_balance': False, 'multi_job_id': '', 'pass_through': True}, collector, 'collector-list')
+    assert not missing
+    prepared['images'] = [images[:2], images[2:]]
+    prepared['audio'] = [audio, audio]
+    result = await execution._async_map_node_over_list(
+        'v3-acceptance', 'collector-list', collector, prepared, collector.FUNCTION, v3_data=hidden)
+    assert torch.equal(result[0].result[0], images)
+    assert result[0].result[1]['waveform'].shape[-1] == 66
+    # Exercise real async aggregation without an HTTP endpoint or worker.
+    queue = asyncio.Queue()
+    await queue.put({'worker_id': 'worker_2', 'tensor': images[2:3], 'image_index': 0, 'is_last': True})
+    prompt_server.distributed_pending_jobs['v3-aggregate'] = queue
+    result = await map_node(collector,
+                            {'images': images[:2], 'load_balance': False,
+                             'multi_job_id': 'v3-aggregate', 'enabled_worker_ids': '["worker_2"]'})
+    assert torch.equal(result[0].result[0], images[:3])
+    assert 'v3-aggregate' not in prompt_server.distributed_pending_jobs
+
+    # The registered node must forward the transfer options to the runtime
+    # helper, and default to the legacy transfer when they are not set.
+    collector_runtime = sys.modules[module.__name__ + '.nodes.collector'].DistributedCollectorNode
+    forwarded = []
+    def fake_run(self, **kwargs):
+        forwarded.append(kwargs)
+        return (kwargs['images'], kwargs['audio'])
+    with patch.object(collector_runtime, 'run', fake_run):
+        await map_node(collector, {'images': images[:1], 'load_balance': False, 'pass_through': True,
+                                   'transfer_format': 'av1', 'transfer_quality': 70})
+        await map_node(collector, {'images': images[:1], 'load_balance': False, 'pass_through': True})
+    # Set values arrive list-wrapped (is_input_list); unset ones use the
+    # execute() defaults. The runtime helper unwraps both forms.
+    assert [(kw['transfer_format'], kw['transfer_quality']) for kw in forwarded] == [
+        (['av1'], [70]), ('legacy_png', 90)], forwarded
+
+    # Prove V3's per-execution class clones do not leak helper instance state;
+    # replace only the GPU/model boundary, not the input parser or executor.
+    upscale_runtime = sys.modules[module.__name__ + '.nodes.distributed_upscale'].UltimateSDUpscaleDistributed
+    seen = []
+    def fake_upscale(self, *args):
+        assert not hasattr(self, 'acceptance_marker')
+        self.acceptance_marker = True
+        seen.append(args)
+        return (args[0],)
+    inputs = {'upscaled_image': images, 'model': object(), 'positive': [], 'negative': [],
+              'vae': object(), 'seed': 1, 'steps': 1, 'cfg': 1.0,
+              'sampler_name': 'euler', 'scheduler': 'normal', 'denoise': 0.5,
+              'tile_width': 64, 'tile_height': 64, 'padding': 0, 'mask_blur': 0,
+              'force_uniform_tiles': True, 'tiled_decode': False,
+              'multi_job_id': 'tile-job', 'is_worker': True, 'master_url': 'http://master.invalid',
+              'enabled_worker_ids': '["worker_2"]', 'worker_id': 'worker_2',
+              'tile_indices': '[2,3]', 'dynamic_threshold': 9}
+    with patch.object(upscale_runtime, 'run', fake_upscale):
+        for _ in range(2):
+            result = await map_node(mapping['UltimateSDUpscaleDistributed'], inputs)
+            assert result[0].result[0] is images
+    assert len(seen) == 2 and seen[0][-7:] == tuple(inputs[name] for name in (
+        'multi_job_id', 'is_worker', 'master_url', 'enabled_worker_ids', 'worker_id',
+        'tile_indices', 'dynamic_threshold')), seen[0]
+    import math
+    assert math.isnan(mapping['UltimateSDUpscaleDistributed'].fingerprint_inputs(multi_job_id='tile-job'))
+    assert math.isnan(mapping['UltimateSDUpscaleDistributed'].fingerprint_inputs(multi_job_id=''))
+
+    graph = {
+        '1': {'class_type': 'EmptyImage', 'inputs': {'height': 8, 'width': 8, 'batch_size': 10, 'color': 0}},
+        '2': {'class_type': 'DistributedCollector', 'inputs': {'images': ['1', 0], 'load_balance': False,
+                                                              'pass_through': True}},
+        '3': {'class_type': 'ImageBatchDivider', 'inputs': {'images': ['2', 0], 'divide_by': 10}},
+        '4': {'class_type': 'PreviewImage', 'inputs': {'images': ['3', 9]}},
+    }
+    valid = await execution.validate_prompt('v3-graph', graph, None)
+    assert valid[0], valid
+    invalid = {'1': {'class_type': 'UltimateSDUpscaleDistributed',
+                     'inputs': {**inputs, 'sampler_name': 'INVALID_ENUM', 'scheduler': 'INVALID_ENUM'}},
+               '2': {'class_type': 'PreviewImage', 'inputs': {'images': ['1', 0]}}}
+    rejected = await execution.validate_prompt('v3-invalid', invalid, None)
+    assert not rejected[0]
+    errors = [error for entry in rejected[3].values() for error in entry['errors']]
+    enum_errors = [error['extra_info']['input_name'] for error in errors if error['type'] == 'value_not_in_list']
+    assert {'sampler_name', 'scheduler'} <= set(enum_errors), errors
+    import folder_paths
+    scratch = Path(os.environ.get('TMPDIR', Path.home() / '.hermes/cache/scratch'))
+    with tempfile.TemporaryDirectory(prefix='v3-preview-', dir=scratch) as temp:
+        with patch.object(folder_paths, 'temp_directory', temp):
+            executor = execution.PromptExecutor(
+                prompt_server, cache_args={'ram': 0, 'ram_inactive': 0}, asset_manager=asset_manager)
+            await asyncio.to_thread(executor.execute, graph, 'v3-graph', {}, valid[2])
+            assert executor.success, executor.status_messages
+            history = executor.history_result
+            record = history['outputs']['4']['images'][0]
+            preview = Path(temp) / record.get('subfolder', '') / record['filename']
+            with Image.open(preview) as image:
+                assert image.size == (8, 8) and image.mode == 'RGB'
+                assert image.getextrema() == ((0, 0), (0, 0), (0, 0))
+
+    # A worker prompt terminated by the sink validates and runs through the
+    # real executor without writing anything to the temp directory.
+    sink_graph = {
+        '1': {'class_type': 'EmptyImage', 'inputs': {'height': 8, 'width': 8, 'batch_size': 4, 'color': 0}},
+        '2': {'class_type': 'DistributedCollector', 'inputs': {'images': ['1', 0], 'load_balance': False,
+                                                              'pass_through': True}},
+        '3': {'class_type': 'DistributedWorkerSink', 'inputs': {'value': ['2', 0]}},
+    }
+    valid = await execution.validate_prompt('v3-sink', sink_graph, None)
+    assert valid[0], valid
+    assert valid[2] == ['3'], valid[2]
+    collected = []
+    def record_run(self, **kwargs):
+        collected.append(kwargs['images'])
+        return (kwargs['images'][0], None)
+    with tempfile.TemporaryDirectory(prefix='v3-sink-', dir=scratch) as temp:
+        with patch.object(folder_paths, 'temp_directory', temp), patch.object(collector_runtime, 'run', record_run):
+            executor = execution.PromptExecutor(
+                prompt_server, cache_args={'ram': 0, 'ram_inactive': 0}, asset_manager=asset_manager)
+            await asyncio.to_thread(executor.execute, sink_graph, 'v3-sink', {}, valid[2])
+            assert executor.success, executor.status_messages
+            assert len(collected) == 1 and collected[0][0].shape == (4, 8, 8, 3), collected
+            assert list(Path(temp).rglob('*')) == [], list(Path(temp).rglob('*'))
+            assert executor.history_result['outputs'].get('3', {}) == {}, executor.history_result
+    print('V3_EXECUTION_OK nine nodes; upscale GPU boundary mocked; preview artifact verified; sink writes nothing')
+
+
+async def main():
+    asset_manager = default_asset_manager()
+    prompt_server = server.PromptServer(asyncio.get_running_loop(), asset_manager)
+    assert not (ROOT / 'distributed.py').exists(), 'obsolete root bootstrap remains'
+    assert await nodes.load_custom_node(str(ROOT)), 'ComfyUI loader rejected the pack'
+    module = sys.modules[str(ROOT).replace('.', '_x_')]
+    assert not hasattr(module, 'NODE_CLASS_MAPPINGS'), 'V1 map shadows V3 entrypoint'
+    extension = await module.comfy_entrypoint()
+    classes = await extension.get_node_list()
+    mapping = {cls.GET_SCHEMA().node_id: cls for cls in classes}
+    assert len(classes) == len(mapping) == len(BASELINE) + len(ADDED_NODES) == 9
+    assert set(mapping) == set(BASELINE) | ADDED_NODES
+    for node_id in ADDED_NODES:
+        assert nodes.NODE_CLASS_MAPPINGS[node_id] is mapping[node_id]
+    sink_info = mapping['DistributedWorkerSink'].GET_NODE_INFO_V1()
+    assert sink_info['output_node'] and sink_info['dev_only'], sink_info
+    for node_id, cls in mapping.items():
+        if node_id in ADDED_NODES:
+            continue
+        assert issubclass(cls, io.ComfyNode)
+        assert nodes.NODE_CLASS_MAPPINGS[node_id] is cls
+        old = dict(BASELINE[node_id])
+        if node_id in ('ImageBatchDivider', 'AudioBatchDivider'):
+            # V1's ByPassTypeTuple advertises '*' when indexed, while its
+            # underlying tuple and existing frontend declare IMAGE/AUDIO.
+            # Native V3 declares all ten existing typed sockets explicitly.
+            assert old['output'] == ['*'] * 10
+            old['output'] = ['IMAGE' if node_id == 'ImageBatchDivider' else 'AUDIO'] * 10
+        new = json.loads(json.dumps(cls.GET_NODE_INFO_V1()))
+        for group in ('required', 'optional'):
+            old_inputs = old['input'].get(group, {})
+            new_inputs = dict(new['input'].get(group, {}))
+            if group == 'optional':
+                for name, expected in ADDED_OPTIONAL_INPUTS.get(node_id, {}).items():
+                    assert name in new_inputs, (node_id, name, 'added input missing')
+                    actual = normalized_input(new_inputs.pop(name))
+                    kind, opts = normalized_input(expected)
+                    assert actual[0] == kind, (node_id, name, actual)
+                    for key, value in opts.items():
+                        assert actual[1].get(key) == value, (node_id, name, key, actual)
+            assert list(old_inputs) == list(new_inputs), (node_id, group, 'input order')
+            for name, original in old_inputs.items():
+                assert normalized_input(original) == normalized_input(new_inputs[name]), (node_id, name, original, new_inputs[name])
+        for key in ('output', 'output_name', 'output_is_list', 'is_input_list', 'output_node', 'category', 'display_name'):
+            assert old[key] == new[key], (node_id, key, old[key], new[key])
+        # Standard context lives in cls.hidden; orchestrator metadata remains
+        # accepted by its original kwarg name, without creating new widgets.
+        signature = inspect.signature(cls.execute)
+        for name, field in old['input'].get('hidden', {}).items():
+            if isinstance(field, list):
+                assert cls.GET_SCHEMA().accept_all_inputs, node_id
+                assert name in signature.parameters, (node_id, name)
+                assert signature.parameters[name].default == field[1]['default'], (node_id, name)
+            else:
+                assert name in new['input']['hidden'], (node_id, name)
+        expected_hidden = []
+        if node_id == 'DistributedModelName':
+            expected_hidden.extend(['unique_id', 'extra_pnginfo'])
+        if old['output_node']:
+            expected_hidden.extend(name for name in ['prompt', 'extra_pnginfo'] if name not in expected_hidden)
+        assert list(new['input'].get('hidden', {})) == expected_hidden, (node_id, new['input'].get('hidden'))
+    print('SCHEMA_PARITY_OK', len(mapping))
+    check_saved_workflows(mapping)
+    await check_execution(mapping, module, prompt_server, asset_manager)
+    print('V3_ACCEPTANCE_OK')
+
+
+asyncio.run(main())

tests/test_collector_list_inputs.py

@@ -7,6 +7,17 @@ from pathlib import Path
 import torch
 
 
+def _register_real_transfer_codec(package_name, utils_pkg):
+    """Load the real utils/transfer_codec.py into the synthetic test package."""
+    codec_path = Path(__file__).resolve().parents[1] / "utils" / "transfer_codec.py"
+    codec_spec = importlib.util.spec_from_file_location(f"{package_name}.utils.transfer_codec", codec_path)
+    codec_module = importlib.util.module_from_spec(codec_spec)
+    sys.modules[f"{package_name}.utils.transfer_codec"] = codec_module
+    codec_spec.loader.exec_module(codec_module)
+    utils_pkg.transfer_codec = codec_module
+    return codec_module
+
+
 def _load_collector_module():
     module_path = Path(__file__).resolve().parents[1] / "nodes" / "collector.py"
     package_name = "dist_collector_list_testpkg"
@@ -26,6 +37,7 @@ def _load_collector_module():
     utils_pkg = types.ModuleType(f"{package_name}.utils")
     utils_pkg.__path__ = []
     sys.modules[f"{package_name}.utils"] = utils_pkg
+    _register_real_transfer_codec(package_name, utils_pkg)
 
     class _Routes:
         def post(self, _path):
@@ -86,6 +98,8 @@ def _load_collector_module():
 
     constants_module = types.ModuleType(f"{package_name}.utils.constants")
     constants_module.HEARTBEAT_INTERVAL = 1.0
+    constants_module.TRANSFER_MAX_CHUNK_BYTES = 32 * 1024 * 1024
+    constants_module.TRANSFER_MAX_REQUEST_BYTES = 96 * 1024 * 1024
     sys.modules[f"{package_name}.utils.constants"] = constants_module
 
     image_module = types.ModuleType(f"{package_name}.utils.image")
@@ -362,3 +376,255 @@ def test_delegate_only_audio_collects_worker_audio_without_placeholder_image():
     assert images is None
     assert combined_audio["sample_rate"] == 48000
     assert torch.equal(combined_audio["waveform"], worker_audio["waveform"])
+
+
+# --------------------------------------------------------------------------- #
+# Compressed worker -> master transfer
+# --------------------------------------------------------------------------- #
+
+class _RecordingResponse:
+    def __init__(self, status=200, text=""):
+        self.status = status
+        self._text = text
+
+    async def __aenter__(self):
+        return self
+
+    async def __aexit__(self, exc_type, exc, tb):
+        return False
+
+    async def text(self):
+        return self._text
+
+    def raise_for_status(self):
+        if self.status >= 400:
+            raise RuntimeError(f"HTTP {self.status}")
+
+
+class _RecordingSession:
+    def __init__(self, statuses=None, text="Invalid JSON payload"):
+        self.calls = []
+        self._statuses = list(statuses or [])
+        self._text = text
+
+    def post(self, url, timeout, json=None, data=None):
+        self.calls.append({"url": url, "json": json, "data": data, "timeout": timeout.total})
+        status = self._statuses.pop(0) if self._statuses else 200
+        return _RecordingResponse(status=status, text=self._text)
+
+
+def _install_fake_transport(module, session):
+    async def _fake_get_client_session():
+        return session
+
+    module.get_client_session = _fake_get_client_session
+    # Record the multipart content instead of building a real aiohttp.FormData.
+    module.DistributedCollectorNode._build_multipart = staticmethod(
+        lambda envelope, parts: {"envelope": envelope, "parts": list(parts)}
+    )
+
+
+def _run_worker(collector, images, audio=None, **kwargs):
+    return collector.run(
+        images=[images],
+        audio=[audio],
+        multi_job_id=["job-c"],
+        is_worker=[True],
+        master_url=["http://master"],
+        worker_id=["worker-a"],
+        **{key: [value] for key, value in kwargs.items()},
+    )
+
+
+def test_collector_exposes_transfer_widgets_with_legacy_default():
+    module = _load_collector_module()
+    optional = module.DistributedCollectorNode.INPUT_TYPES()["optional"]
+
+    formats, options = optional["transfer_format"]
+    assert "legacy_png" in formats and "h264" in formats and "ffv1" in formats
+    assert options["default"] == "legacy_png"
+    assert optional["transfer_quality"][0] == "INT"
+
+
+def test_worker_sends_video_batch_as_one_multipart_chunk_with_audio_on_last():
+    module = _load_collector_module()
+    collector = module.DistributedCollectorNode()
+    session = _RecordingSession()
+    _install_fake_transport(module, session)
+    module.encode_audio_payload = lambda value: None if value is None else {"encoded": True}
+    images = torch.rand(6, 32, 48, 3)
+
+    _run_worker(
+        collector,
+        images,
+        audio={"waveform": torch.ones(1, 2, 4), "sample_rate": 48000},
+        transfer_format="ffv1",
+        transfer_quality=90,
+    )
+
+    assert len(session.calls) == 1
+    call = session.calls[0]
+    assert call["url"] == "http://master/distributed/job_complete"
+    assert call["json"] is None
+    envelope = call["data"]["envelope"]
+    assert envelope["format"] == "ffv1"
+    assert (envelope["start_index"], envelope["count"]) == (0, 6)
+    assert (envelope["width"], envelope["height"]) == (48, 32)
+    assert envelope["is_last"] is True
+    assert envelope["audio"] == {"encoded": True}
+    assert envelope["job_id"] == "job-c" and envelope["worker_id"] == "worker-a"
+    assert len(call["data"]["parts"]) == 1
+
+
+def test_worker_marks_only_final_chunk_as_last():
+    module = _load_collector_module()
+    collector = module.DistributedCollectorNode()
+    session = _RecordingSession()
+    _install_fake_transport(module, session)
+    module.TRANSFER_MAX_CHUNK_BYTES = 1  # force one frame per request
+
+    _run_worker(collector, torch.rand(3, 8, 8, 3), transfer_format="png")
+
+    envelopes = [call["data"]["envelope"] for call in session.calls]
+    assert [(e["start_index"], e["count"], e["is_last"]) for e in envelopes] == [
+        (0, 1, False),
+        (1, 1, False),
+        (2, 1, True),
+    ]
+    assert "audio" not in envelopes[-1]
+
+
+def test_worker_falls_back_to_legacy_png_when_master_rejects_multipart():
+    from PIL import Image
+    import numpy as np
+
+    module = _load_collector_module()
+    collector = module.DistributedCollectorNode()
+    session = _RecordingSession(statuses=[400])
+    _install_fake_transport(module, session)
+    module.tensor_to_pil = lambda tensor, idx: Image.fromarray(
+        (255 * tensor[idx].cpu().numpy()).astype(np.uint8)
+    )
+
+    _run_worker(collector, torch.rand(2, 8, 8, 3), transfer_format="h264")
+
+    assert session.calls[0]["data"] is not None  # compressed attempt
+    legacy = [call["json"] for call in session.calls[1:]]
+    assert [payload["batch_idx"] for payload in legacy] == [0, 1]
+    assert all(payload["image"].startswith("data:image/png;base64,") for payload in legacy)
+    assert [payload["is_last"] for payload in legacy] == [False, True]
+
+
+def test_worker_uses_legacy_path_for_unknown_transfer_format():
+    from PIL import Image
+    import numpy as np
+
+    module = _load_collector_module()
+    collector = module.DistributedCollectorNode()
+    session = _RecordingSession()
+    _install_fake_transport(module, session)
+    module.tensor_to_pil = lambda tensor, idx: Image.fromarray(
+        (255 * tensor[idx].cpu().numpy()).astype(np.uint8)
+    )
+
+    _run_worker(collector, torch.rand(1, 8, 8, 3), transfer_format="gif")
+
+    assert len(session.calls) == 1
+    assert session.calls[0]["json"]["image"].startswith("data:image/png;base64,")
+
+
+def test_worker_falls_back_when_video_encoder_missing():
+    module = _load_collector_module()
+    collector = module.DistributedCollectorNode()
+    session = _RecordingSession()
+    _install_fake_transport(module, session)
+    codec = module.transfer_codec
+    original = codec.video_codec_available
+    codec.video_codec_available = lambda fmt: fmt == "h264" and original("h264")
+    try:
+        _run_worker(collector, torch.rand(2, 16, 16, 3), transfer_format="av1")
+    finally:
+        codec.video_codec_available = original
+
+    assert session.calls[0]["data"]["envelope"]["format"] == "h264"
+
+
+def test_worker_does_not_fall_back_on_non_legacy_rejection():
+    import pytest
+
+    module = _load_collector_module()
+    collector = module.DistributedCollectorNode()
+    session = _RecordingSession(statuses=[400], text="Invalid multipart payload: Request Entity Too Large")
+    _install_fake_transport(module, session)
+
+    with pytest.raises(RuntimeError, match="MAX_REQUEST_BYTES"):
+        _run_worker(collector, torch.rand(2, 8, 8, 3), transfer_format="png")
+
+    # One compressed attempt, no legacy resend of the batch.
+    assert len(session.calls) == 1
+    assert session.calls[0]["json"] is None
+
+
+def test_worker_sends_nothing_when_a_frame_cannot_fit():
+    import numpy as np
+    import pytest
+
+    module = _load_collector_module()
+    collector = module.DistributedCollectorNode()
+    session = _RecordingSession()
+    _install_fake_transport(module, session)
+    reserve = module.DistributedCollectorNode.TRANSFER_ENVELOPE_RESERVE_BYTES
+    module.TRANSFER_MAX_REQUEST_BYTES = reserve + 32 * 1024
+    module.TRANSFER_MAX_CHUNK_BYTES = 32 * 1024
+    # Frame 0 is tiny; frame 2 is noise that cannot fit in 32 KiB as PNG.
+    images = torch.zeros(3, 128, 128, 3)
+    images[2] = torch.from_numpy(np.random.default_rng(1).random((128, 128, 3), dtype=np.float32))
+
+    with pytest.raises(module.transfer_codec.FrameTooLargeError):
+        _run_worker(collector, images, transfer_format="png")
+
+    assert session.calls == []
+
+
+def test_worker_sends_audio_separately_when_it_would_overflow_last_request():
+    module = _load_collector_module()
+    collector = module.DistributedCollectorNode()
+    session = _RecordingSession()
+    _install_fake_transport(module, session)
+    reserve = module.DistributedCollectorNode.TRANSFER_ENVELOPE_RESERVE_BYTES
+    module.TRANSFER_MAX_REQUEST_BYTES = reserve + 64 * 1024
+    module.TRANSFER_MAX_CHUNK_BYTES = 64 * 1024
+    module.encode_audio_payload = lambda value: None if value is None else {"data": "x" * (128 * 1024)}
+
+    _run_worker(
+        collector,
+        torch.zeros(2, 16, 16, 3),
+        audio={"waveform": torch.ones(1, 2, 4), "sample_rate": 48000},
+        transfer_format="png",
+    )
+
+    multipart = [call["data"]["envelope"] for call in session.calls if call["data"] is not None]
+    assert [e["is_last"] for e in multipart] == [False]
+    assert all("audio" not in e for e in multipart)
+    final = session.calls[-1]["json"]
+    assert final["is_last"] is True and final["audio"]["data"].startswith("x")
+    assert "image" not in final
+
+
+def test_worker_attaches_audio_to_last_chunk_when_it_fits():
+    module = _load_collector_module()
+    collector = module.DistributedCollectorNode()
+    session = _RecordingSession()
+    _install_fake_transport(module, session)
+    module.encode_audio_payload = lambda value: None if value is None else {"data": "small"}
+
+    _run_worker(
+        collector,
+        torch.zeros(2, 16, 16, 3),
+        audio={"waveform": torch.ones(1, 2, 4), "sample_rate": 48000},
+        transfer_format="png",
+    )
+
+    assert len(session.calls) == 1
+    envelope = session.calls[0]["data"]["envelope"]
+    assert envelope["is_last"] is True and envelope["audio"] == {"data": "small"}

tests/test_config.py

@@ -18,7 +18,7 @@ def _load_config_module():
             del sys.modules[mod_name]
 
     root_pkg = types.ModuleType(package_name)
-    root_pkg.__path__ = []
+    root_pkg.__path__ = [str(module_path.parent)]
     sys.modules[package_name] = root_pkg
 
     logging_module = types.ModuleType(f"{package_name}.logging")

tests/test_payload_parsers.py

@@ -86,27 +86,25 @@ class ParseTilesFromFormTests(unittest.TestCase):
 
     # --- happy paths ---
 
-    def test_single_tile_returns_one_entry(self):
+    def test_single_tile_returns_image_and_metadata(self):
         tiles = pp._parse_tiles_from_form(_make_form(1))
         self.assertEqual(len(tiles), 1)
-
-    def test_multiple_tiles_all_returned(self):
-        tiles = pp._parse_tiles_from_form(_make_form(3))
-        self.assertEqual(len(tiles), 3)
-
-    def test_tile_image_is_pil_image(self):
-        tiles = pp._parse_tiles_from_form(_make_form(1))
-        self.assertIsInstance(tiles[0]["image"], PILImage.Image)
-
-    def test_tile_metadata_fields_are_parsed(self):
-        tiles = pp._parse_tiles_from_form(_make_form(1))
         tile = tiles[0]
+        self.assertIsInstance(tile["image"], PILImage.Image)
         self.assertEqual(tile["tile_idx"], 0)
         self.assertEqual(tile["x"], 0)
         self.assertEqual(tile["y"], 0)
         self.assertEqual(tile["extracted_width"], 64)
         self.assertEqual(tile["extracted_height"], 64)
 
+    def test_multiple_tiles_preserve_count_order_and_coordinates(self):
+        tiles = pp._parse_tiles_from_form(_make_form(3))
+        self.assertEqual(len(tiles), 3)
+        for i, tile in enumerate(tiles):
+            self.assertEqual(tile["tile_idx"], i)
+        self.assertEqual(tiles[1]["x"], 64)
+        self.assertEqual(tiles[2]["x"], 128)
+
     def test_padding_is_parsed_from_form(self):
         tiles = pp._parse_tiles_from_form(_make_form(1, padding=16))
         self.assertEqual(tiles[0]["padding"], 16)
@@ -138,16 +136,6 @@ class ParseTilesFromFormTests(unittest.TestCase):
         self.assertNotIn("batch_idx", tiles[0])
         self.assertNotIn("global_idx", tiles[0])
 
-    def test_tile_indices_match_metadata_order(self):
-        tiles = pp._parse_tiles_from_form(_make_form(3))
-        for i, tile in enumerate(tiles):
-            self.assertEqual(tile["tile_idx"], i)
-
-    def test_x_coordinates_reflect_metadata(self):
-        tiles = pp._parse_tiles_from_form(_make_form(3))
-        self.assertEqual(tiles[1]["x"], 64)
-        self.assertEqual(tiles[2]["x"], 128)
-
     # --- error cases ---
 
     def test_missing_tiles_metadata_raises_value_error(self):

tests/test_prompt_transform.py

@@ -260,6 +260,40 @@ class PrunePromptForWorkerTests(unittest.TestCase):
         preview_nodes = [n for n in result.values() if n.get("class_type") == "PreviewImage"]
         self.assertEqual(len(preview_nodes), 0)
 
+    def test_worker_sink_replaces_preview_image(self):
+        result = pt.prune_prompt_for_worker(_linear_prompt(), use_worker_sink=True)
+        sinks = [n for n in result.values() if n.get("class_type") == pt.WORKER_SINK_CLASS]
+        self.assertEqual(len(sinks), 1)
+        self.assertEqual(sinks[0]["inputs"], {"value": ["4", 0]})
+        self.assertFalse(any(n.get("class_type") in ("PreviewImage", "PreviewAudio") for n in result.values()))
+
+    def test_worker_sink_uses_audio_output_for_audio_only_collector(self):
+        result = pt.prune_prompt_for_worker(_audio_only_prompt(), use_worker_sink=True)
+        sinks = [n for n in result.values() if n.get("class_type") == pt.WORKER_SINK_CLASS]
+        self.assertEqual([s["inputs"] for s in sinks], [{"value": ["2", 1]}])
+        self.assertFalse(any(n.get("class_type") == "PreviewAudio" for n in result.values()))
+
+    def test_worker_sink_for_distributed_upscale(self):
+        prompt = {
+            "1": {"class_type": "LoadImage", "inputs": {}},
+            "2": {"class_type": "UltimateSDUpscaleDistributed", "inputs": {"upscaled_image": ["1", 0]}},
+            "3": {"class_type": "SaveImage", "inputs": {"images": ["2", 0]}},
+        }
+        result = pt.prune_prompt_for_worker(prompt, use_worker_sink=True)
+        sinks = [n for n in result.values() if n.get("class_type") == pt.WORKER_SINK_CLASS]
+        self.assertEqual([s["inputs"] for s in sinks], [{"value": ["2", 0]}])
+        self.assertNotIn("3", result)
+
+    def test_worker_sink_ids_do_not_collide_with_original_prompt(self):
+        prompt = _linear_prompt()
+        result = pt.prune_prompt_for_worker(prompt, use_worker_sink=True)
+        sink_ids = [k for k, n in result.items() if n.get("class_type") == pt.WORKER_SINK_CLASS]
+        self.assertTrue(all(k not in prompt for k in sink_ids))
+
+    def test_no_worker_sink_when_no_downstream(self):
+        result = pt.prune_prompt_for_worker(_collector_only_prompt(), use_worker_sink=True)
+        self.assertFalse(any(n.get("class_type") == pt.WORKER_SINK_CLASS for n in result.values()))
+
     def test_unrelated_nodes_are_pruned(self):
         prompt = {
             "1": {"class_type": "DistributedCollector", "inputs": {}},
@@ -302,8 +336,8 @@ class PrepareDelegateMasterPromptTests(unittest.TestCase):
         self.assertNotIn("1", result)
         self.assertNotIn("2", result)
 
-    def test_removes_dangling_upstream_refs(self):
-        """Collector must not retain dangling refs to pruned upstream nodes."""
+    def test_replaces_dangling_upstream_ref_with_one_empty_image_placeholder(self):
+        """Collector must point to exactly one valid placeholder after pruning."""
         prompt = _delegate_prompt()
         result = pt.prepare_delegate_master_prompt(prompt, ["3"])
         collector_inputs = result["3"].get("inputs", {})
@@ -314,10 +348,6 @@ class PrepareDelegateMasterPromptTests(unittest.TestCase):
         self.assertNotEqual(source_id, "2")
         self.assertIn(source_id, result)
         self.assertEqual(result[source_id].get("class_type"), "DistributedEmptyImage")
-
-    def test_injects_empty_image_placeholder(self):
-        prompt = _delegate_prompt()
-        result = pt.prepare_delegate_master_prompt(prompt, ["3"])
         empty_nodes = [(nid, n) for nid, n in result.items() if n.get("class_type") == "DistributedEmptyImage"]
         self.assertEqual(len(empty_nodes), 1)
         placeholder_id = empty_nodes[0][0]
@@ -384,13 +414,6 @@ class PrepareDelegateMasterPromptTests(unittest.TestCase):
         self.assertEqual(result["15"], prompt["15"])
         self.assertEqual(result["9"]["inputs"]["filename_prefix"], ["15", 0])
 
-    def test_does_not_preserve_non_primitive_upstream_for_collector(self):
-        prompt = _delegate_prompt()
-        result = pt.prepare_delegate_master_prompt(prompt, ["3"])
-
-        self.assertNotIn("2", result)
-        self.assertNotEqual(result["3"]["inputs"]["images"], ["2", 0])
-
     def test_preserves_load_image_for_switch_alternate_required_input(self):
         """Delegate-only master keeps LoadImage inputs needed by switches."""
         prompt = {

tests/test_runpod_client.py

@@ -0,0 +1,167 @@
+import importlib.util
+import json
+import sys
+import unittest
+from pathlib import Path
+
+ROOT = Path(__file__).resolve().parents[1]
+
+def load_module():
+    spec = importlib.util.spec_from_file_location("dist_runpod_client", ROOT / "api/orchestration/runpod_client.py")
+    module = importlib.util.module_from_spec(spec)
+    sys.modules[spec.name] = module
+    spec.loader.exec_module(module)
+    return module
+
+client = load_module()
+
+
+def workflow_for_request_size(target_size, timeout_seconds):
+    """Build an ASCII workflow whose compact UTF-8 request body has exact size."""
+    workflow = {"1": {"class_type": "Text", "inputs": {"value": ""}}}
+
+    def body_size(candidate):
+        payload = {
+            "input": {"workflow": candidate, "images": []},
+            "policy": {
+                "executionTimeout": timeout_seconds * 1000,
+                "ttl": timeout_seconds * 1000,
+            },
+        }
+        return len(json.dumps(
+            payload, allow_nan=False, ensure_ascii=False, separators=(",", ":")
+        ).encode("utf-8"))
+
+    padding = target_size - body_size(workflow)
+    if padding < 0:
+        raise AssertionError("target is smaller than the request fixture")
+    workflow["1"]["inputs"]["value"] = "x" * padding
+    if body_size(workflow) != target_size:
+        raise AssertionError("request fixture did not reach the exact target size")
+    return workflow
+
+class Response:
+    def __init__(self, status=200, payload=None):
+        self.status, self.payload = status, payload
+    async def __aenter__(self):
+        return self
+    async def __aexit__(self, *args):
+        return False
+    async def json(self):
+        return self.payload
+
+class Session:
+    def __init__(self, responses):
+        self.responses, self.calls = list(responses), []
+    def request(self, method, url, **kwargs):
+        self.calls.append((method, url, kwargs))
+        response = self.responses.pop(0)
+        if isinstance(response, Exception):
+            raise response
+        return response
+
+class ClientTests(unittest.IsolatedAsyncioTestCase):
+    async def test_submit_exact_generic_contract_and_once(self):
+        session = Session([Response(payload={"id": "job-1", "status": "IN_QUEUE"})])
+        api = client.RunpodClient(session, "endpoint123", "secret-value")
+        result = await api.submit({"1": {"class_type": "EmptyImage", "inputs": {}}}, [], 1800)
+        self.assertEqual(result, "job-1")
+        method, url, kwargs = session.calls[0]
+        self.assertEqual((method, url), ("POST", "https://api.runpod.ai/v2/endpoint123/run"))
+        self.assertIsInstance(kwargs["data"], bytes)
+        sent_payload = json.loads(kwargs["data"])
+        self.assertEqual(set(sent_payload["input"]), {"workflow", "images"})
+        self.assertEqual(sent_payload["policy"]["ttl"], 1800000)
+        self.assertFalse(kwargs["allow_redirects"])
+        self.assertEqual(kwargs["headers"]["Authorization"], "Bearer secret-value")
+
+    async def test_submit_timeout_is_ambiguous_and_never_retried(self):
+        session = Session([TimeoutError("secret-value in unsafe error")])
+        api = client.RunpodClient(session, "endpoint123", "secret-value")
+        with self.assertRaises(client.AmbiguousSubmission) as ctx:
+            await api.submit({}, [], 30)
+        self.assertNotIn("secret-value", str(ctx.exception))
+        self.assertEqual(len(session.calls), 1)
+
+    async def test_http_submit_failure_not_retried_or_leaked(self):
+        for status in [401, 429, 500, 302]:
+            session = Session([Response(status, {"error": "secret-value"})])
+            api = client.RunpodClient(session, "endpoint123", "secret-value")
+            with self.assertRaises(client.RunpodError) as ctx:
+                await api.submit({}, [], 30)
+            self.assertEqual(len(session.calls), 1)
+            self.assertNotIn("secret-value", str(ctx.exception))
+
+    async def test_health_zero_workers_is_valid(self):
+        session = Session([Response(payload={"workers": {"idle": 0}, "jobs": {"inQueue": 0}})])
+        api = client.RunpodClient(session, "endpoint123", "key")
+        self.assertEqual((await api.health())["workers"]["idle"], 0)
+
+    async def test_invalid_provider_id_no_network(self):
+        session = Session([])
+        with self.assertRaises(ValueError):
+            client.RunpodClient(session, "https://attacker.invalid", "key")
+        api = client.RunpodClient(session, "endpoint123", "key")
+        with self.assertRaises(ValueError):
+            await api.status("../other")
+        self.assertFalse(session.calls)
+
+    async def test_status_and_cancel_only_target_exact_job(self):
+        session = Session([Response(payload={"status": "IN_PROGRESS"}), Response(payload={"status": "CANCELLED"})])
+        api = client.RunpodClient(session, "endpoint123", "key")
+        await api.status("job-1")
+        await api.cancel("job-1")
+        self.assertEqual([c[:2] for c in session.calls], [("GET", "https://api.runpod.ai/v2/endpoint123/status/job-1"), ("POST", "https://api.runpod.ai/v2/endpoint123/cancel/job-1")])
+
+    async def test_missing_id_is_ambiguous(self):
+        api = client.RunpodClient(Session([Response(payload={"status": "IN_QUEUE"})]), "endpoint123", "key")
+        with self.assertRaises(client.AmbiguousSubmission):
+            await api.submit({}, [], 30)
+
+    async def test_large_payload_rejected_before_submit(self):
+        session = Session([])
+        api = client.RunpodClient(session, "endpoint123", "key")
+        with self.assertRaises(ValueError):
+            await api.submit({}, [{"image": "x" * client.MAX_REQUEST_BYTES}], 30)
+        self.assertFalse(session.calls)
+
+    async def test_exact_10mb_serialized_request_is_sent_as_validated_bytes(self):
+        session = Session([Response(payload={"id": "boundary-job"})])
+        api = client.RunpodClient(session, "endpoint123", "key")
+        timeout_seconds = 37
+        workflow = workflow_for_request_size(10_000_000, timeout_seconds)
+
+        result = await api.submit(workflow, [], timeout_seconds)
+
+        self.assertEqual(result, "boundary-job")
+        sent = session.calls[0][2]["data"]
+        self.assertIsInstance(sent, bytes)
+        self.assertEqual(len(sent), 10_000_000)
+        self.assertEqual(json.loads(sent)["policy"]["executionTimeout"], 37_000)
+
+    async def test_one_byte_over_10mb_is_rejected_without_request_or_payload_leak(self):
+        session = Session([Response(payload={"id": "must-not-be-used"})])
+        api = client.RunpodClient(session, "endpoint123", "key")
+        workflow = workflow_for_request_size(10_000_001, 37)
+        workflow["1"]["inputs"]["value"] = "private graph value" + workflow["1"]["inputs"]["value"][19:]
+
+        with self.assertRaisesRegex(ValueError, "10,000,001") as ctx:
+            await api.submit(workflow, [], 37)
+
+        self.assertNotIn("private graph value", str(ctx.exception))
+        self.assertFalse(session.calls)
+
+    async def test_wire_size_counts_utf8_graph_bytes_and_policy_fields(self):
+        session = Session([Response(payload={"id": "unicode-job"})])
+        api = client.RunpodClient(session, "endpoint123", "key")
+        workflow = {"1": {"class_type": "Text", "inputs": {"value": "café雪"}}}
+
+        await api.submit(workflow, [], 41)
+
+        sent = session.calls[0][2]["data"]
+        expected = json.dumps({
+            "input": {"workflow": workflow, "images": []},
+            "policy": {"executionTimeout": 41_000, "ttl": 41_000},
+        }, allow_nan=False, ensure_ascii=False, separators=(",", ":")).encode("utf-8")
+        self.assertEqual(sent, expected)
+        self.assertGreater(len(sent), len(sent.decode("utf-8")))

tests/test_serverless_collector.py

@@ -0,0 +1,202 @@
+import asyncio
+
+import pytest
+import torch
+
+from test_collector_list_inputs import _load_collector_module
+
+
+class _FakeManager:
+    def __init__(self, *, pending=False, owned=True):
+        self.pending = pending
+        self.owned = owned
+        self.pending_calls = []
+        self.owned_calls = []
+        self.cancel_calls = []
+
+    def is_pending(self, collector_job_id, participant_id):
+        self.pending_calls.append((collector_job_id, participant_id))
+        return self.pending
+
+    def owns(self, collector_job_id, participant_id):
+        self.owned_calls.append((collector_job_id, participant_id))
+        return self.owned
+
+    async def cancel(self, worker_id=None, execution_id=None, collector_job_id=None):
+        self.cancel_calls.append({
+            "worker_id": worker_id,
+            "execution_id": execution_id,
+            "collector_job_id": collector_job_id,
+        })
+        return 1
+
+
+def _set_up_collector(module, job_id, queue, manager=None):
+    module.prompt_server.distributed_jobs_lock = asyncio.Lock()
+    module.prompt_server.distributed_pending_jobs = {job_id: queue}
+    if manager is not None:
+        module.prompt_server.distributed_serverless = manager
+    return module.DistributedCollectorNode()
+
+
+def test_serverless_pending_waits_past_normal_worker_timeout():
+    module = _load_collector_module()
+    job_id = "collector-pending"
+    participant = "serverless:pool:1"
+    queue = asyncio.Queue()
+    manager = _FakeManager(pending=True)
+    collector = _set_up_collector(module, job_id, queue, manager)
+    module.get_worker_timeout_seconds = lambda: 0.01
+    module.HEARTBEAT_INTERVAL = 0.1
+    probe_calls = []
+    module.probe_worker = lambda *args, **kwargs: probe_calls.append(args)
+
+    async def deliver_after_provider_work():
+        await asyncio.sleep(0.14)
+        queue.put_nowait({
+            "worker_id": participant,
+            "image_index": 0,
+            "tensor": torch.ones(1, 2, 2, 2),
+            "is_last": True,
+        })
+
+    async def run_collection():
+        producer = asyncio.create_task(deliver_after_provider_work())
+        result = await collector.execute(
+            images=None,
+            audio=None,
+            multi_job_id=job_id,
+            enabled_worker_ids=f'["{participant}"]',
+            delegate_only=True,
+        )
+        await producer
+        return result
+
+    images, _audio = asyncio.run(run_collection())
+
+    assert tuple(images.shape) == (1, 2, 2, 2)
+    assert manager.pending_calls
+    assert probe_calls == []
+    assert job_id not in module.prompt_server.distributed_pending_jobs
+
+
+def test_serverless_queue_error_raises_and_cancels_only_collector_binding():
+    module = _load_collector_module()
+    job_id = "collector-error"
+    queue = asyncio.Queue()
+    queue.put_nowait({
+        "worker_id": "serverless:pool:1",
+        "serverless_error": "Provider execution failed safely",
+        "is_last": True,
+    })
+    manager = _FakeManager()
+    collector = _set_up_collector(module, job_id, queue, manager)
+
+    with pytest.raises(RuntimeError, match="serverless.*Provider execution failed safely"):
+        asyncio.run(collector.execute(
+            images=None,
+            audio=None,
+            multi_job_id=job_id,
+            enabled_worker_ids='["serverless:pool:1"]',
+            delegate_only=True,
+        ))
+
+    assert manager.cancel_calls == [{
+        "worker_id": None,
+        "execution_id": None,
+        "collector_job_id": job_id,
+    }]
+    assert job_id not in module.prompt_server.distributed_pending_jobs
+
+
+def test_owned_serverless_slot_without_pending_result_fails_instead_of_partial_success():
+    module = _load_collector_module()
+    job_id = "collector-stopped"
+    queue = asyncio.Queue()
+    manager = _FakeManager(pending=False, owned=True)
+    collector = _set_up_collector(module, job_id, queue, manager)
+    module.get_worker_timeout_seconds = lambda: 0.01
+    module.HEARTBEAT_INTERVAL = 0.1
+    module.probe_worker = lambda *_args, **_kwargs: pytest.fail("serverless slots are not worker URLs")
+
+    with pytest.raises(RuntimeError, match="serverless.*stopped.*result|serverless.*result.*stopped"):
+        asyncio.run(collector.execute(
+            images=None,
+            audio=None,
+            multi_job_id=job_id,
+            enabled_worker_ids='["serverless:pool:1"]',
+            delegate_only=True,
+        ))
+
+    assert manager.owned_calls
+    assert manager.cancel_calls[0]["collector_job_id"] == job_id
+    assert job_id not in module.prompt_server.distributed_pending_jobs
+
+
+def test_interruption_cancels_serverless_job_and_removes_collector_queue():
+    module = _load_collector_module()
+    job_id = "collector-interrupted"
+    queue = asyncio.Queue()
+    manager = _FakeManager(pending=True)
+    collector = _set_up_collector(module, job_id, queue, manager)
+    interrupted = module.comfy.model_management.InterruptProcessingException("stop")
+    module.comfy.model_management.throw_exception_if_processing_interrupted = lambda: (_ for _ in ()).throw(interrupted)
+
+    with pytest.raises(module.comfy.model_management.InterruptProcessingException, match="stop"):
+        asyncio.run(collector.execute(
+            images=None,
+            audio=None,
+            multi_job_id=job_id,
+            enabled_worker_ids='["serverless:pool:1"]',
+            delegate_only=True,
+        ))
+
+    assert manager.cancel_calls[0]["collector_job_id"] == job_id
+    assert job_id not in module.prompt_server.distributed_pending_jobs
+
+
+def test_serverless_tensor_shape_mismatch_raises_instead_of_silent_fallback():
+    module = _load_collector_module()
+    job_id = "collector-shape-mismatch"
+    queue = asyncio.Queue()
+    queue.put_nowait({
+        "worker_id": "serverless:pool:1",
+        "image_index": 0,
+        "tensor": torch.ones(1, 3, 2, 2),
+        "is_last": True,
+    })
+    manager = _FakeManager()
+    collector = _set_up_collector(module, job_id, queue, manager)
+    local_images = torch.zeros(1, 2, 2, 2)
+
+    with pytest.raises(RuntimeError, match="serverless.*shape|shape.*serverless"):
+        asyncio.run(collector.execute(
+            images=local_images,
+            audio=None,
+            multi_job_id=job_id,
+            enabled_worker_ids='["serverless:pool:1"]',
+        ))
+
+    assert manager.cancel_calls[0]["collector_job_id"] == job_id
+    assert job_id not in module.prompt_server.distributed_pending_jobs
+
+
+def test_regular_worker_timeout_keeps_partial_behavior_without_creating_manager():
+    module = _load_collector_module()
+    job_id = "collector-regular-timeout"
+    queue = asyncio.Queue()
+    collector = _set_up_collector(module, job_id, queue)
+    module.get_worker_timeout_seconds = lambda: 0.01
+    module.HEARTBEAT_INTERVAL = 0.1
+    local_images = torch.zeros(1, 2, 2, 2)
+    collector._get_serverless_manager = lambda *_args, **_kwargs: pytest.fail("regular collection must not create manager")
+
+    images, _audio = asyncio.run(collector.execute(
+        images=local_images,
+        audio=None,
+        multi_job_id=job_id,
+        enabled_worker_ids='["worker-a"]',
+    ))
+
+    assert torch.equal(images, local_images)
+    assert job_id not in module.prompt_server.distributed_pending_jobs

tests/test_serverless_config.py

@@ -0,0 +1,410 @@
+import importlib.util
+import json
+import os
+import stat
+import sys
+import tempfile
+import threading
+import types
+import unittest
+from pathlib import Path
+from unittest import mock
+
+
+def _load_serverless_config_module(*, without_fcntl=False):
+    module_path = Path(__file__).resolve().parents[1] / "utils" / "serverless_config.py"
+    module_name = (
+        "dist_serverless_config_no_fcntl_test_module"
+        if without_fcntl
+        else "dist_serverless_config_test_module"
+    )
+    package_name = module_name + "_pkg"
+    package = types.ModuleType(package_name)
+    package.__path__ = [str(module_path.parent)]
+    sys.modules[package_name] = package
+    module_name = package_name + ".serverless_config"
+    sys.modules.pop(module_name, None)
+    spec = importlib.util.spec_from_file_location(module_name, module_path)
+    assert spec is not None and spec.loader is not None
+    module = importlib.util.module_from_spec(spec)
+    sys.modules[module_name] = module
+    if without_fcntl:
+        with mock.patch.dict(sys.modules, {"fcntl": None}):
+            spec.loader.exec_module(module)
+    else:
+        spec.loader.exec_module(module)
+    return module
+
+
+serverless_config = _load_serverless_config_module()
+
+
+class ValidateServerlessWorkerTests(unittest.TestCase):
+    def test_returns_copy_with_runpod_defaults(self):
+        worker = {"id": "worker-1", "endpoint_id": "ep_123-abc", "name": "GPU"}
+
+        result = serverless_config.validate_serverless_worker(worker)
+
+        self.assertEqual(
+            result,
+            {
+                "id": "worker-1",
+                "endpoint_id": "ep_123-abc",
+                "name": "GPU",
+                "type": "serverless",
+                "provider": "runpod",
+                "jobs_per_run": 1,
+                "timeout_seconds": 1800,
+            },
+        )
+        self.assertIsNot(result, worker)
+        self.assertEqual(worker, {"id": "worker-1", "endpoint_id": "ep_123-abc", "name": "GPU"})
+
+    def test_accepts_inclusive_numeric_bounds(self):
+        for jobs, timeout in ((1, 30), (16, 86400)):
+            with self.subTest(jobs=jobs, timeout=timeout):
+                result = serverless_config.validate_serverless_worker(
+                    {
+                        "id": "worker-1",
+                        "endpoint_id": "ep-123",
+                        "jobs_per_run": jobs,
+                        "timeout_seconds": timeout,
+                    }
+                )
+                self.assertEqual(result["jobs_per_run"], jobs)
+                self.assertEqual(result["timeout_seconds"], timeout)
+
+    def test_legacy_concurrency_is_accepted_and_dropped(self):
+        # Configs saved before Images per run replaced the separate setting.
+        for legacy in (1, 2, 16, 17, True, "3"):
+            with self.subTest(legacy=legacy):
+                result = serverless_config.validate_serverless_worker(
+                    {"id": "worker-1", "endpoint_id": "ep-123", "jobs_per_run": 2, "concurrency": legacy}
+                )
+                self.assertNotIn("concurrency", result)
+                self.assertEqual(result["jobs_per_run"], 2)
+
+    def test_endpoint_url_is_rejected_with_a_plain_message(self):
+        with self.assertRaisesRegex(ValueError, "not a URL"):
+            serverless_config.validate_serverless_worker(
+                {"id": "worker-1", "endpoint_id": "https://api.runpod.ai/v2/abc123/run"}
+            )
+
+    def test_rejects_missing_or_empty_id_and_endpoint(self):
+        base: dict[str, object] = {"id": "worker-1", "endpoint_id": "ep-123"}
+        for field, value in (("id", None), ("id", "  "), ("endpoint_id", ""), ("endpoint_id", "https://api.runpod.io/ep-123")):
+            with self.subTest(field=field, value=value):
+                worker = dict(base)
+                worker[field] = value
+                with self.assertRaises(ValueError):
+                    serverless_config.validate_serverless_worker(worker)
+
+        worker = dict(base)
+        del worker["id"]
+        with self.assertRaises(ValueError):
+            serverless_config.validate_serverless_worker(worker)
+
+    def test_endpoint_id_must_be_ascii_opaque_identifier(self):
+        for endpoint_id in ("ep/123", "ep 123", "ép-123", "ep:123", "https://example.test"):
+            with self.subTest(endpoint_id=endpoint_id):
+                with self.assertRaises(ValueError):
+                    serverless_config.validate_serverless_worker(
+                        {"id": "worker-1", "endpoint_id": endpoint_id}
+                    )
+
+    def test_endpoint_id_matches_runpod_client_length_limit(self):
+        valid_id = "e" * 200
+        result = serverless_config.validate_serverless_worker(
+            {"id": "worker-1", "endpoint_id": valid_id}
+        )
+        self.assertEqual(result["endpoint_id"], valid_id)
+        with self.assertRaises(ValueError):
+            serverless_config.validate_serverless_worker(
+                {"id": "worker-1", "endpoint_id": "e" * 201}
+            )
+
+    def test_enabled_must_be_boolean_when_supplied(self):
+        base = {"id": "worker-1", "endpoint_id": "ep-123"}
+        for enabled in (True, False):
+            with self.subTest(enabled=enabled):
+                self.assertIs(
+                    serverless_config.validate_serverless_worker(
+                        {**base, "enabled": enabled}
+                    )["enabled"],
+                    enabled,
+                )
+        for enabled in ("false", 0, 1, None):
+            with self.subTest(enabled=enabled):
+                with self.assertRaises(ValueError):
+                    serverless_config.validate_serverless_worker(
+                        {**base, "enabled": enabled}
+                    )
+
+    def test_rejects_unknown_provider_and_non_serverless_type(self):
+        base = {"id": "worker-1", "endpoint_id": "ep-123"}
+        for extra in ({"provider": "other"}, {"type": "local"}):
+            with self.subTest(extra=extra):
+                with self.assertRaises(ValueError):
+                    serverless_config.validate_serverless_worker({**base, **extra})
+
+    def test_numeric_fields_reject_bool_float_and_out_of_range(self):
+        base = {"id": "worker-1", "endpoint_id": "ep-123"}
+        invalid_values = {
+            "jobs_per_run": (True, 1.0, 0, 17),
+            "timeout_seconds": (True, 30.0, 29, 86401),
+        }
+        for field, values in invalid_values.items():
+            for value in values:
+                with self.subTest(field=field, value=value):
+                    with self.assertRaises(ValueError):
+                        serverless_config.validate_serverless_worker({**base, field: value})
+
+    def test_requires_worker_object(self):
+        for worker in (None, [], "worker"):
+            with self.subTest(worker=worker):
+                with self.assertRaises(ValueError):
+                    serverless_config.validate_serverless_worker(worker)
+
+
+class SecretStoreTests(unittest.TestCase):
+    def setUp(self):
+        self.tempdir = tempfile.TemporaryDirectory()
+        self.root = Path(self.tempdir.name)
+        self.path = self.root / "private" / "runpod-secrets.json"
+
+    def tearDown(self):
+        self.tempdir.cleanup()
+
+    def test_set_get_has_delete_and_persists_as_json_mapping(self):
+        store = serverless_config.SecretStore(self.path)
+        store.set("worker-1", "secret-value")
+
+        self.assertEqual(store.get("worker-1"), "secret-value")
+        self.assertTrue(store.has("worker-1"))
+        self.assertIsNone(store.get("missing"))
+        self.assertFalse(store.has("missing"))
+        self.assertEqual(json.loads(self.path.read_text(encoding="utf-8")), {"worker-1": "secret-value"})
+        self.assertEqual(serverless_config.SecretStore(self.path).get("worker-1"), "secret-value")
+
+        store.delete("worker-1")
+        self.assertIsNone(store.get("worker-1"))
+        self.assertFalse(store.has("worker-1"))
+
+    def test_rejects_api_keys_with_newlines_or_over_4096_characters(self):
+        store = serverless_config.SecretStore(self.path)
+        for key in ("key\nwith-line-feed", "key\rwith-carriage-return", "k" * 4097):
+            with self.subTest(key_length=len(key)):
+                with self.assertRaises(serverless_config.SecretStoreError):
+                    store.set("worker-1", key)
+        store.set("worker-1", "k" * 4096)
+        self.assertEqual(store.get("worker-1"), "k" * 4096)
+
+    def test_new_secret_file_and_directory_have_restrictive_modes(self):
+        store = serverless_config.SecretStore(self.path)
+        store.set("worker-1", "secret-value")
+
+        self.assertEqual(stat.S_IMODE(self.path.stat().st_mode), 0o600)
+        self.assertEqual(stat.S_IMODE(self.path.parent.stat().st_mode), 0o700)
+
+    def test_missing_store_reads_as_empty_without_creating_files(self):
+        store = serverless_config.SecretStore(self.path)
+
+        self.assertIsNone(store.get("worker-1"))
+        self.assertFalse(store.has("worker-1"))
+        self.assertFalse(self.path.parent.exists())
+
+    def test_corrupt_store_fails_closed_without_overwriting_or_leaking_contents(self):
+        self.path.parent.mkdir()
+        corrupt = b'{"partial": "NEVER-LEAK-THIS-secret'
+        self.path.write_bytes(corrupt)
+        store = serverless_config.SecretStore(self.path)
+
+        for operation in (
+            lambda: store.get("worker-1"),
+            lambda: store.set("worker-1", "replacement-secret"),
+            lambda: store.delete("worker-1"),
+        ):
+            with self.subTest(operation=operation):
+                with self.assertRaises(Exception) as raised:
+                    operation()
+                self.assertNotIn("NEVER-LEAK-THIS", str(raised.exception))
+                self.assertNotIn("replacement-secret", str(raised.exception))
+                self.assertEqual(self.path.read_bytes(), corrupt)
+
+    def test_rejects_non_mapping_or_non_string_store_values_without_leaking_data(self):
+        for corrupt in (b'["opaque-stored-value"]', b'{"worker": 23}', b'{"": "opaque-stored-value"}'):
+            with self.subTest(corrupt=corrupt):
+                self.path.parent.mkdir(exist_ok=True)
+                self.path.write_bytes(corrupt)
+                with self.assertRaises(Exception) as raised:
+                    serverless_config.SecretStore(self.path).get("worker")
+                self.assertNotIn("opaque-stored-value", str(raised.exception))
+
+    def test_rejects_symlink_file_and_preserves_link_target(self):
+        target = self.root / "target.json"
+        target.write_text('{"worker-1": "target-secret"}', encoding="utf-8")
+        self.path.parent.mkdir()
+        self.path.symlink_to(target)
+        store = serverless_config.SecretStore(self.path)
+
+        with self.assertRaises(Exception):
+            store.get("worker-1")
+        with self.assertRaises(Exception):
+            store.set("worker-1", "replacement-secret")
+        self.assertEqual(target.read_text(encoding="utf-8"), '{"worker-1": "target-secret"}')
+
+    def test_rejects_symlinked_parent_directory(self):
+        real_dir = self.root / "real"
+        real_dir.mkdir()
+        link_dir = self.root / "linked"
+        link_dir.symlink_to(real_dir, target_is_directory=True)
+        store = serverless_config.SecretStore(link_dir / "secrets.json")
+
+        with self.assertRaises(Exception):
+            store.set("worker-1", "secret-value")
+        self.assertFalse((real_dir / "secrets.json").exists())
+
+    def test_rejects_parent_traversal_in_store_path(self):
+        store = serverless_config.SecretStore(self.root / "nested" / ".." / "secrets.json")
+
+        with self.assertRaises(Exception):
+            store.set("worker-1", "secret-value")
+        self.assertFalse((self.root / "secrets.json").exists())
+
+    def test_threaded_updates_from_independent_instances_are_not_lost(self):
+        workers = 12
+        barrier = threading.Barrier(workers)
+        errors = []
+
+        def write_one(index):
+            try:
+                barrier.wait(timeout=5)
+                serverless_config.SecretStore(self.path).set(f"worker-{index}", f"key-{index}")
+            except Exception as exc:  # collected to fail in the test thread
+                errors.append(exc)
+
+        threads = [threading.Thread(target=write_one, args=(i,)) for i in range(workers)]
+        for thread in threads:
+            thread.start()
+        for thread in threads:
+            thread.join(timeout=10)
+
+        self.assertFalse(any(thread.is_alive() for thread in threads), "writer thread did not finish")
+        self.assertEqual(errors, [])
+        saved = json.loads(self.path.read_text(encoding="utf-8"))
+        self.assertEqual(saved, {f"worker-{i}": f"key-{i}" for i in range(workers)})
+
+
+class PublicConfigTests(unittest.TestCase):
+    def test_redacts_credentials_preserves_other_fields_and_marks_only_serverless(self):
+        with tempfile.TemporaryDirectory() as tempdir:
+            store = serverless_config.SecretStore(Path(tempdir) / "private" / "keys.json")
+            store.set("serverless-1", "stored-api-key")
+            config = {
+                "workers": [
+                    {
+                        "id": "serverless-1",
+                        "type": "serverless",
+                        "provider": "runpod",
+                        "endpoint_id": "ep-123",
+                        "api_key": "inline-secret",
+                        "clear_api_key": "another-secret",
+                        "credential": "credential-secret",
+                        "nested": {"runpod_credential": "nested-secret", "safe": "kept"},
+                        "name": "remote GPU",
+                    },
+                    {"id": "serverless-2", "type": "serverless", "name": "not configured"},
+                    {"id": "local-1", "type": "local", "api_key": "local-secret"},
+                ],
+                "settings": {"mode": "preserved", "credentials_note": "remove-me"},
+            }
+            original = json.loads(json.dumps(config))
+
+            result = serverless_config.public_config(config, store)
+
+        first, second, local = result["workers"]
+        self.assertEqual(first["api_key_configured"], True)
+        self.assertEqual(second["api_key_configured"], False)
+        self.assertNotIn("api_key_configured", local)
+        self.assertNotIn("api_key", first)
+        self.assertNotIn("clear_api_key", first)
+        self.assertNotIn("credential", first)
+        self.assertNotIn("runpod_credential", first["nested"])
+        self.assertEqual(first["nested"]["safe"], "kept")
+        self.assertNotIn("api_key", local)
+        self.assertNotIn("credentials_note", result["settings"])
+        self.assertEqual(first["name"], "remote GPU")
+        self.assertEqual(config, original)
+        self.assertIsNot(result, config)
+        self.assertIsNot(result["workers"], config["workers"])
+
+    def test_redacts_normalized_secret_field_aliases(self):
+        config = {
+            "workers": [{
+                "id": "serverless-1",
+                "type": "serverless",
+                "apiKey": "camel-api-key",
+                "APIKEY": "upper-api-key",
+                "clearApiKey": "camel-clear-key",
+                "CLEAR_API_KEY": "upper-clear-key",
+                "runpod_CREDENTIAL": "provider-credential",
+                "nested": {"credential_note": "nested-credential"},
+                "safe": "preserved",
+            }]
+        }
+
+        result = serverless_config.public_config(
+            config, serverless_config.SecretStore(self.root_path())
+        )
+
+        worker = result["workers"][0]
+        self.assertEqual(worker, {
+            "id": "serverless-1",
+            "type": "serverless",
+            "nested": {},
+            "safe": "preserved",
+            "api_key_configured": False,
+        })
+
+    def test_handles_non_dict_config_without_mutating_it(self):
+        config = ["safe", {"api_key": "secret"}]
+        result = serverless_config.public_config(config, serverless_config.SecretStore(self.root_path()))
+        self.assertEqual(result, ["safe", {}])
+        self.assertEqual(config, ["safe", {"api_key": "secret"}])
+
+    def test_module_import_and_non_serverless_redaction_when_fcntl_unavailable(self):
+        module = _load_serverless_config_module(without_fcntl=True)
+        store = module.SecretStore(self.root_path())
+        config = {
+            "workers": [
+                {"id": "local-1", "type": "local", "api_key": "inline-secret"}
+            ]
+        }
+
+        result = module.public_config(config, store)
+
+        self.assertEqual(result, {"workers": [{"id": "local-1", "type": "local"}]})
+        self.assertEqual(config["workers"][0]["api_key"], "inline-secret")
+
+    def test_secret_operations_fail_clearly_without_fcntl(self):
+        module = _load_serverless_config_module(without_fcntl=True)
+        store = module.SecretStore(self.root_path())
+        unsupported_message = "Serverless credential storage is currently supported on POSIX masters only"
+
+        for operation in (
+            lambda: store.get("worker-1"),
+            lambda: store.set("worker-1", "api-key"),
+            lambda: store.delete("worker-1"),
+            lambda: store.has("worker-1"),
+        ):
+            with self.subTest(operation=operation):
+                with self.assertRaisesRegex(module.SecretStoreError, unsupported_message):
+                    operation()
+
+    @staticmethod
+    def root_path():
+        return Path(tempfile.gettempdir()) / "not-created-serverless-secret-store" / "secrets.json"
+
+
+if __name__ == "__main__":
+    unittest.main()

tests/test_serverless_integration.py

@@ -0,0 +1,183 @@
+"""Offline integration: real graph preparation + orchestration, fake provider."""
+import asyncio
+import aiohttp as real_aiohttp
+import importlib.util
+import json
+import sys
+import types
+import unittest
+from pathlib import Path
+from unittest.mock import AsyncMock, patch
+
+ROOT = Path(__file__).resolve().parents[1]
+PKG = "dist_serverless_integration"
+
+
+def module(name, **attrs):
+    value = types.ModuleType(name)
+    value.__dict__.update(attrs)
+    return value
+
+
+def load_modules():
+    modules = {}
+    for part, directory in [("", ROOT), (".api", ROOT / "api"), (".api.orchestration", ROOT / "api/orchestration"), (".utils", ROOT / "utils")]:
+        modules[PKG + part] = module(PKG + part, __path__=[str(directory)])
+    ps = types.SimpleNamespace(routes=types.SimpleNamespace(get=lambda _: lambda fn: fn, post=lambda _: lambda fn: fn))
+    modules["server"] = module("server", PromptServer=types.SimpleNamespace(instance=ps))
+    modules[PKG + ".utils.logging"] = module("logging", debug_log=lambda *a: None, log=lambda *a: None)
+    modules[PKG + ".utils.trace_logger"] = module("trace_logger", trace_debug=lambda *a: None)
+    modules[PKG + ".utils.config"] = module("config", load_config=lambda: {})
+    modules[PKG + ".utils.async_helpers"] = module("async_helpers", queue_prompt_payload=AsyncMock())
+    modules[PKG + ".utils.network"] = module("network", build_master_url=lambda **k: "http://master", build_master_callback_url=lambda *a, **k: "http://master")
+    modules[PKG + ".api.orchestration.dispatch"] = module("dispatch", dispatch_worker_prompt=AsyncMock(), select_active_workers=AsyncMock(), select_least_busy_worker=AsyncMock())
+    modules[PKG + ".api.orchestration.media_sync"] = module("media_sync", convert_paths_for_platform=lambda p, _: p, fetch_worker_path_separator=AsyncMock(), fetch_worker_has_node=AsyncMock(return_value=False), sync_worker_media=AsyncMock())
+    with patch.dict(sys.modules, modules):
+        spec = importlib.util.spec_from_file_location(PKG + ".api.queue_orchestration", ROOT / "api/queue_orchestration.py")
+        q = importlib.util.module_from_spec(spec)
+        spec.loader.exec_module(q)
+        # Keep imported package namespace only; restore shared Comfy runtime stub.
+        modules.update({k: v for k, v in sys.modules.items() if k.startswith(PKG)})
+    return q, modules, ps
+
+
+class IntegrationTests(unittest.IsolatedAsyncioTestCase):
+    async def asyncSetUp(self):
+        self.q, modules, self.ps = load_modules()
+        self.patch = patch.dict(sys.modules, modules)
+        self.patch.start()
+        self.addCleanup(self.patch.stop)
+        self.pool = {"id": "pool", "name": "Runpod", "type": "serverless", "provider": "runpod", "endpoint_id": "endpoint", "enabled": True, "jobs_per_run": 2, "concurrency": 1, "timeout_seconds": 30}
+        self.q.load_config = lambda: {"workers": [self.pool], "settings": {"master_delegate_only": True}}
+        self.q.select_active_workers = AsyncMock(side_effect=lambda workers, _ws, delegate, **kw: (workers, delegate))
+        self.q.queue_prompt_payload = AsyncMock(return_value={"prompt_id": "master-prompt", "number": 1})
+        self.manager = types.SimpleNamespace(start=AsyncMock(), cancel=AsyncMock(), ensure_capacity=lambda _: None)
+        sys.modules[PKG + ".api.orchestration.serverless_runtime"] = module("runtime", get_manager=lambda: self.manager)
+        sys.modules[PKG + ".api.orchestration.serverless_media"] = module("media", prepare_images=AsyncMock(return_value=[]))
+        self.prompt = {
+            "1": {"class_type": "EmptyImage", "inputs": {"width": 32, "height": 32, "batch_size": 1, "color": 0}},
+            "2": {"class_type": "DistributedCollector", "inputs": {"images": ["1", 0], "load_balance": False}},
+            "3": {"class_type": "SaveImage", "inputs": {"images": ["2", 0], "filename_prefix": "local"}},
+        }
+
+    async def test_real_compiler_slots_to_master_collector_without_callbacks(self):
+        result = await self.q.orchestrate_distributed_execution(self.prompt, None, "client")
+        self.assertEqual(result[2], 2)
+        self.q.dispatch_worker_prompt.assert_not_awaited()
+        self.manager.start.assert_awaited_once()
+        jobs = self.manager.start.call_args.args[2]
+        self.assertEqual([job["worker"]["id"] for job in jobs], ["serverless:pool:1", "serverless:pool:2"])
+        self.assertEqual(len({job["manifest"][0]["prefix"] for job in jobs}), 2)
+        for job in jobs:
+            graph = job["workflow"]
+            self.assertTrue(any(n["class_type"] == "SaveImage" for n in graph.values()))
+            self.assertFalse(any("Distributed" in n["class_type"] for n in graph.values()))
+            self.assertNotIn("http://master", json.dumps(graph))
+        master_graph = self.q.queue_prompt_payload.call_args.args[0]
+        self.assertEqual(json.loads(master_graph["2"]["inputs"]["enabled_worker_ids"]), ["serverless:pool:1", "serverless:pool:2"])
+
+    async def test_compile_pack_provider_decode_and_collect_real_components(self):
+        """Exercise the whole image path, mocking only the provider and Comfy queue."""
+        import base64
+        import io
+        import tempfile
+        import torch
+        from PIL import Image
+        from test_collector_list_inputs import _load_collector_module
+
+        sys.modules["aiohttp"] = real_aiohttp
+        for leaf in ("serverless_media", "serverless_runtime"):
+            name = PKG + ".api.orchestration." + leaf
+            spec = importlib.util.spec_from_file_location(name, ROOT / "api/orchestration" / (leaf + ".py"))
+            real_module = importlib.util.module_from_spec(spec)
+            sys.modules[name] = real_module
+            spec.loader.exec_module(real_module)
+        runtime = sys.modules[PKG + ".api.orchestration.serverless_runtime"]
+        with tempfile.TemporaryDirectory() as directory:
+            root = Path(directory)
+            image_buffer = io.BytesIO()
+            Image.new("RGB", (2, 3), color=(255, 0, 128)).save(image_buffer, format="PNG")
+            image_bytes = image_buffer.getvalue()
+            (root / "source.png").write_bytes(image_bytes)
+            paths = module("folder_paths", get_input_directory=lambda: directory,
+                           get_output_directory=lambda: directory, get_temp_directory=lambda: directory,
+                           get_annotated_filepath=lambda name: str(root / name))
+            submissions = []
+
+            class FakeProvider:
+                async def submit(self, graph, images, timeout_seconds):
+                    self.prefix = next(n["inputs"]["filename_prefix"] for n in graph.values() if n["class_type"] == "SaveImage")
+                    submissions.append((graph, images))
+                    self_image = next(n["inputs"]["image"] for n in graph.values() if n["class_type"] == "LoadImage")
+                    assert self_image == images[0]["name"]
+                    assert base64.b64decode(images[0]["image"]) == image_bytes
+                    return "provider-job-" + str(len(submissions))
+
+                async def status(self, _job_id):
+                    filename = self.prefix + "_00001_.png"
+                    return {"status": "COMPLETED", "output": {"images": [{
+                        "filename": filename, "artifact_path": filename, "artifact_type": "output",
+                        "type": "base64", "data": base64.b64encode(image_bytes).decode(),
+                    }]}}
+
+            manager = runtime.ServerlessManager(self.ps, None, root / "state" / "jobs.json", None)
+            manager._client = AsyncMock(side_effect=lambda _: FakeProvider())
+            self.ps.distributed_serverless = manager
+            self.prompt["1"] = {"class_type": "LoadImage", "inputs": {"image": "source.png"}}
+            collector_module = _load_collector_module()
+            collector_module.prompt_server = self.ps
+            sys.modules["aiohttp"] = real_aiohttp
+            with patch.object(runtime, "get_manager", return_value=manager), patch.dict(sys.modules, {"folder_paths": paths}):
+                result = await self.q.orchestrate_distributed_execution(self.prompt, None, "client")
+                master_graph = self.q.queue_prompt_payload.call_args.args[0]
+                inputs = master_graph["2"]["inputs"]
+                images, _audio = await asyncio.wait_for(collector_module.DistributedCollectorNode().execute(
+                    images=None, audio=None, multi_job_id=inputs["multi_job_id"],
+                    enabled_worker_ids=inputs["enabled_worker_ids"], delegate_only=True,
+                ), timeout=3)
+                await asyncio.gather(*manager.tasks.values())
+            self.assertEqual(result[2], 2)
+            self.assertEqual(len(submissions), 2)
+            self.assertEqual(tuple(images.shape), (2, 3, 2, 3))
+            self.assertEqual(images.dtype, torch.float32)
+            self.assertTrue(torch.equal(images[0], images[1]))
+            self.assertEqual(float(images[0, 0, 0, 0]), 1.0)
+            self.assertEqual([record["status"] for record in manager.ledger.all()], ["COMPLETED", "COMPLETED"])
+            self.assertEqual(self.ps.distributed_pending_jobs, {})
+            self.q.dispatch_worker_prompt.assert_not_awaited()
+
+    async def test_audio_rejected_before_any_dispatch_or_master_queue(self):
+        self.prompt["2"]["inputs"]["audio"] = ["9", 0]
+        self.prompt["9"] = {"class_type": "LoadAudio", "inputs": {"audio": "test.wav"}}
+        with self.assertRaises(ValueError):
+            await self.q.orchestrate_distributed_execution(self.prompt, None, "client")
+        self.manager.start.assert_not_awaited()
+        self.q.dispatch_worker_prompt.assert_not_awaited()
+        self.q.queue_prompt_payload.assert_not_awaited()
+
+    async def test_disabled_pool_excluded(self):
+        self.pool["enabled"] = False
+        self.assertEqual(self.q._resolve_enabled_workers({"workers": [self.pool]}), [])
+
+    async def test_master_validation_failure_submits_no_paid_job(self):
+        self.q.queue_prompt_payload.side_effect = ValueError("invalid local graph")
+        with self.assertRaisesRegex(ValueError, "invalid local graph"):
+            await self.q.orchestrate_distributed_execution(self.prompt, None, "client")
+        self.manager.start.assert_not_awaited()
+
+    async def test_oversized_serverless_request_fails_before_dispatch_or_master_queue(self):
+        media_module = sys.modules[PKG + ".api.orchestration.serverless_media"]
+        media_module.prepare_images.return_value = [{
+            "name": "private-image-name.png",
+            "image": "x" * 10_000_001,
+        }]
+
+        with self.assertRaisesRegex(ValueError, "10,000,") as ctx:
+            await self.q.orchestrate_distributed_execution(self.prompt, None, "client")
+
+        self.assertNotIn("private-image-name.png", str(ctx.exception))
+        self.assertNotIn("x" * 100, str(ctx.exception))
+        self.q.dispatch_worker_prompt.assert_not_awaited()
+        self.q.queue_prompt_payload.assert_not_awaited()
+        self.manager.start.assert_not_awaited()
+        self.assertEqual(self.ps.distributed_pending_jobs, {})

tests/test_serverless_lifecycle.py

@@ -0,0 +1,198 @@
+"""Billing-safe lifecycle regressions: local completion is not remote completion."""
+import asyncio
+import tempfile
+import types
+import unittest
+from pathlib import Path
+from unittest.mock import AsyncMock, patch
+
+from test_serverless_runtime import runtime, Secrets
+
+
+class LifecycleTests(unittest.IsolatedAsyncioTestCase):
+    async def asyncSetUp(self):
+        self.temp = tempfile.TemporaryDirectory()
+        self.addCleanup(self.temp.cleanup)
+        self.server = types.SimpleNamespace(distributed_pending_jobs={"collector": asyncio.Queue()}, distributed_jobs_lock=asyncio.Lock())
+        self.path = Path(self.temp.name) / "jobs.json"
+        self.manager = runtime.ServerlessManager(self.server, Secrets(), self.path, AsyncMock(return_value=object()))
+        self.worker = {"id": "serverless:pool:1", "pool_id": "pool", "endpoint_id": "ep", "timeout_seconds": 30, "type": "serverless"}
+        self.prepared = {"worker": self.worker, "workflow": {}, "images": [], "manifest": [{"job_id": "collector", "prefix": "x", "kind": "image"}]}
+        self.api = types.SimpleNamespace(submit=AsyncMock(return_value="job"), status=AsyncMock(), cancel=AsyncMock(return_value={"status": "CANCELLED"}))
+        self.client_patch = patch.object(runtime, "RunpodClient", return_value=self.api)
+        self.client_patch.start()
+        self.addCleanup(self.client_patch.stop)
+        self.decode_patch = patch.object(runtime, "decode_results", AsyncMock(return_value={"collector": ["tensor"]}))
+        self.decode_patch.start()
+        self.addCleanup(self.decode_patch.stop)
+        # These regressions exercise capacity holding, so use a limit of one.
+        self.limit_patch = patch.object(runtime, "PER_WORKER_JOB_LIMIT", 1)
+        self.limit_patch.start()
+        self.addCleanup(self.limit_patch.stop)
+
+    async def asyncTearDown(self):
+        await self.manager.cancel()
+
+    def second(self, **changes):
+        return dict(self.prepared, worker=dict(self.worker, id="serverless:pool:2", **changes))
+
+    def retained(self, status="CANCEL_REQUESTED", job_id: str | None = "old-job"):
+        self.manager.ledger.update("old", worker_id="pool", endpoint_id="ep", job_id=job_id,
+                                   status=status, created_at=1, updated_at=1)
+
+    async def test_capacity_is_held_until_slow_cancellation_is_confirmed(self):
+        cancel_started, release_cancel = asyncio.Event(), asyncio.Event()
+        self.api.submit.side_effect = ["job-1", "job-2"]
+        self.api.status.side_effect = [runtime.RunpodError("poll failed"), {"status": "COMPLETED", "output": {}}]
+        async def cancel(_job_id):
+            cancel_started.set()
+            await release_cancel.wait()
+            return {"status": "CANCELLED"}
+        self.api.cancel.side_effect = cancel
+        await self.manager.start("exec", "prompt", [self.prepared, self.second()])
+        try:
+            await asyncio.wait_for(cancel_started.wait(), 1)
+            await asyncio.sleep(0.01)
+            self.assertEqual(self.api.submit.await_count, 1)
+        finally:
+            release_cancel.set()
+            await self.manager.wait_for_execution("exec")
+        self.assertEqual(self.api.submit.await_count, 2)
+
+    async def test_unconfirmed_cancel_holds_capacity_until_reconciled(self):
+        self.api.status.side_effect = runtime.RunpodError("poll failed")
+        self.api.cancel.return_value = {"status": "IN_PROGRESS"}
+        await self.manager.start("first", "prompt", [self.prepared])
+        await self.manager.wait_for_execution("first")
+        self.assertEqual(self.manager.ledger.all()[0]["status"], "CANCEL_REQUESTED")
+        self.assertTrue(self.manager.pool_is_active("pool"))
+        await self.manager.start("second", "prompt", [self.second()])
+        try:
+            await asyncio.sleep(0.01)
+            self.assertEqual(self.api.submit.await_count, 1)
+            self.api.status.side_effect = None
+            self.api.status.return_value = {"status": "COMPLETED", "output": {}}
+            await self.manager.reconcile(worker_id="pool")
+            await asyncio.wait_for(self.manager.wait_for_execution("second"), 1)
+            self.assertEqual(self.api.submit.await_count, 2)
+        finally:
+            self.api.cancel.return_value = {"status": "CANCELLED"}
+            await self.manager.cancel()
+
+    async def test_restarted_manager_reserves_known_unresolved_jobs(self):
+        self.retained("IN_PROGRESS")
+        self.manager = runtime.ServerlessManager(self.server, Secrets(), self.path, AsyncMock(return_value=object()))
+        self.assertTrue(self.manager.pool_is_active("pool"))
+        self.assertFalse(self.manager.pool_is_active("other"))
+        await self.manager.start("exec", "prompt", [self.second(timeout_seconds=0.02)])
+        await self.manager.wait_for_execution("exec")
+        self.api.submit.assert_not_awaited()
+        self.assertEqual(self.manager.ledger.all()[-1]["status"], "TIMED_OUT")
+
+    async def test_recovery_closes_never_submitted_waiting_records(self):
+        self.retained("WAITING", job_id=None)
+        self.manager = runtime.ServerlessManager(self.server, Secrets(), self.path, AsyncMock(return_value=object()))
+        self.assertFalse(self.manager.pool_is_active("pool"))
+        self.assertEqual(self.manager.ledger.all()[0]["status"], "CANCELLED")
+        self.api.submit.assert_not_awaited()
+
+    async def test_recovery_keeps_interrupted_submission_unresolved(self):
+        self.retained("SUBMITTING", job_id=None)
+        self.manager = runtime.ServerlessManager(self.server, Secrets(), self.path, AsyncMock(return_value=object()))
+        self.assertTrue(self.manager.pool_is_active("pool"))
+        self.assertEqual(self.manager.ledger.all()[0]["status"], "UNKNOWN")
+        await self.manager.reconcile(worker_id="pool")
+        self.api.status.assert_not_awaited()
+        self.api.submit.assert_not_awaited()
+
+    async def test_ambiguous_submission_requires_explicit_recovery_acknowledgment(self):
+        self.api.submit.side_effect = runtime.AmbiguousSubmission("acceptance unknown")
+        await self.manager.start("exec", "prompt", [self.prepared])
+        await self.manager.wait_for_execution("exec")
+        record = self.manager.ledger.all()[0]
+        self.assertTrue(self.manager.pool_is_active("pool"))
+        with self.assertRaises(ValueError):
+            await self.manager.acknowledge_recovery("pool", record["record_id"], provider_checked=False)
+        with self.assertRaises(ValueError):
+            await self.manager.acknowledge_recovery("other", record["record_id"], provider_checked=True)
+        await self.manager.acknowledge_recovery("pool", record["record_id"], provider_checked=True)
+        self.assertFalse(self.manager.pool_is_active("pool"))
+        self.assertEqual(self.manager.ledger.all()[0]["status"], "RESOLVED")
+        self.api.submit.assert_awaited_once()
+
+    async def test_cancel_already_completed_provider_job_is_terminal(self):
+        self.retained()
+        self.api.cancel.return_value = {"status": "COMPLETED"}
+        await self.manager.cancel(worker_id="pool")
+        self.assertEqual(self.manager.ledger.all()[0]["status"], "COMPLETED")
+        self.assertFalse(self.manager.pool_is_active("pool"))
+
+    async def test_reconciliation_failure_never_releases_capacity(self):
+        self.retained()
+        self.api.status.side_effect = runtime.RunpodError("not reachable")
+        await self.manager.reconcile(worker_id="pool")
+        self.assertTrue(self.manager.pool_is_active("pool"))
+        self.assertEqual(self.manager.ledger.all()[0]["status"], "CANCEL_REQUESTED")
+
+    async def test_cancel_before_first_task_step_finalizes_local_record(self):
+        await self.manager.start("exec", "prompt", [self.prepared])
+        await self.manager.cancel(worker_id="pool")
+        self.assertEqual(self.manager.ledger.all()[0]["status"], "CANCELLED")
+        self.assertFalse(self.server.distributed_pending_jobs["collector"].empty())
+        self.assertFalse(self.manager.pool_is_active("pool"))
+        self.api.submit.assert_not_awaited()
+
+    async def test_live_record_cannot_be_acknowledged_or_reconciled(self):
+        polling = asyncio.Event()
+        async def status(_job_id):
+            polling.set()
+            await asyncio.Event().wait()
+        self.api.status.side_effect = status
+        await self.manager.start("exec", "prompt", [self.prepared])
+        await asyncio.wait_for(polling.wait(), 1)
+        record = self.manager.ledger.all()[0]
+        with self.assertRaises(ValueError):
+            await self.manager.acknowledge_recovery("pool", record["record_id"], provider_checked=True)
+        await self.manager.reconcile(worker_id="pool")
+        self.assertEqual(self.api.status.await_count, 1)
+        self.assertTrue(self.manager.pool_is_active("pool"))
+
+    async def test_repeated_cancel_does_not_interrupt_provider_cleanup(self):
+        polling, cancelling, release = asyncio.Event(), asyncio.Event(), asyncio.Event()
+        async def status(_job_id):
+            polling.set()
+            await asyncio.Event().wait()
+        async def cancel(_job_id):
+            cancelling.set()
+            await release.wait()
+            return {"status": "CANCELLED"}
+        self.api.status.side_effect = status
+        self.api.cancel.side_effect = cancel
+        await self.manager.start("exec", "prompt", [self.prepared])
+        await polling.wait()
+        first = asyncio.create_task(self.manager.cancel(worker_id="pool"))
+        await cancelling.wait()
+        second = asyncio.create_task(self.manager.cancel(worker_id="pool"))
+        await asyncio.sleep(0)
+        release.set()
+        await asyncio.gather(first, second)
+        self.api.cancel.assert_awaited_once_with("job")
+        self.assertEqual(self.manager.ledger.all()[0]["status"], "CANCELLED")
+
+    async def test_partial_start_cleanup_does_not_leave_waiting_protection(self):
+        broken = self.second()
+        del broken["worker"]["endpoint_id"]
+        with self.assertRaises(KeyError):
+            await self.manager.start("exec", "prompt", [self.prepared, broken])
+        await self.manager.cancel(execution_id="exec")
+        self.assertFalse(self.manager.pool_is_active("pool"))
+        self.api.submit.assert_not_awaited()
+
+    async def test_public_jobs_never_hides_unresolved_recovery_ids(self):
+        for index in range(22):
+            self.manager.ledger.update(str(index), worker_id="pool", endpoint_id="ep", status="UNKNOWN", updated_at=index)
+        for index in range(5):
+            self.manager.ledger.update("done-" + str(index), worker_id="pool", status="COMPLETED", updated_at=30 + index)
+        records = self.manager.public_jobs("pool")
+        self.assertEqual({record["record_id"] for record in records}, {str(index) for index in range(22)})
+        self.assertTrue(all(record["status"] == "UNKNOWN" for record in records))

tests/test_serverless_media.py

@@ -0,0 +1,447 @@
+import base64
+import importlib.util
+import io
+import sys
+import tempfile
+import types
+import unittest
+from pathlib import Path
+from unittest.mock import AsyncMock, patch
+
+from PIL import Image
+
+ROOT = Path(__file__).resolve().parents[1]
+MODULE_PATH = ROOT / "api" / "orchestration" / "serverless_media.py"
+
+
+def load_module():
+    spec = importlib.util.spec_from_file_location("dist_serverless_media_test", MODULE_PATH)
+    assert spec is not None and spec.loader is not None
+    module = importlib.util.module_from_spec(spec)
+    sys.modules[spec.name] = module
+    spec.loader.exec_module(module)
+    return module
+
+
+media = load_module()
+
+
+def load_runpod_module():
+    spec = importlib.util.spec_from_file_location(
+        "dist_serverless_media_runpod_test", ROOT / "api" / "orchestration" / "runpod_client.py"
+    )
+    assert spec is not None and spec.loader is not None
+    module = importlib.util.module_from_spec(spec)
+    sys.modules[spec.name] = module
+    spec.loader.exec_module(module)
+    return module
+
+
+runpod = load_runpod_module()
+
+
+def png_bytes(mode="RGB", size=(2, 1), color=None):
+    if color is None:
+        color = (10, 20, 30, 40) if mode == "RGBA" else (10, 20, 30)
+    buffer = io.BytesIO()
+    Image.new(mode, size, color).save(buffer, format="PNG")
+    return buffer.getvalue()
+
+
+class FolderPathsFixture:
+    def __init__(self, root):
+        self.input = root / "input"
+        self.output = root / "output"
+        self.temp = root / "temp"
+        for directory in (self.input, self.output, self.temp):
+            directory.mkdir(parents=True, exist_ok=True)
+
+    def get_input_directory(self):
+        return str(self.input)
+
+    def get_output_directory(self):
+        return str(self.output)
+
+    def get_temp_directory(self):
+        return str(self.temp)
+
+    def get_annotated_filepath(self, filename):
+        value = filename.replace("\\", "/")
+        # Match real ComfyUI folder_paths: root annotations are suffixes,
+        # not directory prefixes (output/foo.png is an input subdirectory).
+        for marker, root in (("input", self.input), ("output", self.output), ("temp", self.temp)):
+            suffix = f" [{marker}]"
+            if value.endswith(suffix):
+                return str(root / value[:-len(suffix)])
+        return str(self.input / value)
+
+
+class ServerlessMediaInputTests(unittest.IsolatedAsyncioTestCase):
+    async def asyncSetUp(self):
+        self.tempdir = tempfile.TemporaryDirectory()
+        self.paths = FolderPathsFixture(Path(self.tempdir.name))
+        self.folder_paths = types.ModuleType("folder_paths")
+        self.folder_paths.get_input_directory = self.paths.get_input_directory
+        self.folder_paths.get_output_directory = self.paths.get_output_directory
+        self.folder_paths.get_temp_directory = self.paths.get_temp_directory
+        self.folder_paths.get_annotated_filepath = self.paths.get_annotated_filepath
+        self.folder_patch = patch.dict(sys.modules, {"folder_paths": self.folder_paths})
+        self.folder_patch.start()
+        self.addCleanup(self.folder_patch.stop)
+        self.addCleanup(self.tempdir.cleanup)
+
+    async def test_packs_image_and_rewrites_duplicate_loadimage_inputs(self):
+        payload = png_bytes()
+        (self.paths.input / "cat.png").write_bytes(payload)
+        workflow = {
+            "1": {"class_type": "LoadImage", "inputs": {"image": "cat.png [input]", "other": "unchanged"}},
+            "2": {"class_type": "LoadImage", "inputs": {"image": "cat.png [input]"}},
+            "3": {"class_type": "SaveImage", "inputs": {"filename_prefix": "stable"}},
+        }
+
+        packed = await media.prepare_images(workflow)
+
+        self.assertEqual(len(packed), 1)
+        self.assertEqual(set(packed[0]), {"name", "image"})
+        self.assertRegex(packed[0]["name"], r"^[A-Za-z0-9_.-]+\.png$")
+        self.assertEqual(base64.b64decode(packed[0]["image"], validate=True), payload)
+        self.assertEqual(workflow["1"]["inputs"]["image"], packed[0]["name"])
+        self.assertEqual(workflow["2"]["inputs"]["image"], packed[0]["name"])
+        self.assertEqual(workflow["1"]["inputs"]["other"], "unchanged")
+        self.assertEqual(workflow["3"]["inputs"]["filename_prefix"], "stable")
+
+    async def test_resolves_annotated_input_output_and_temp_sources(self):
+        sources = ((self.paths.input, "one.png"), (self.paths.output, "two.jpg"), (self.paths.temp, "three.webp"))
+        workflow = {}
+        for index, (directory, filename) in enumerate(sources, 1):
+            (directory / filename).write_bytes(png_bytes())
+            root = directory.name
+            workflow[str(index)] = {"class_type": "LoadImage", "inputs": {"image": f"{filename} [{root}]"}}
+
+        packed = await media.prepare_images(workflow)
+
+        self.assertEqual(len(packed), 3)
+        self.assertEqual({base64.b64decode(item["image"]) for item in packed}, {png_bytes()})
+        self.assertEqual({node["inputs"]["image"] for node in workflow.values()}, {item["name"] for item in packed})
+
+    async def test_directory_prefix_is_not_a_root_annotation(self):
+        (self.paths.input / "output").mkdir()
+        payload = png_bytes(color=(100, 0, 0))
+        (self.paths.input / "output" / "same.png").write_bytes(payload)
+        (self.paths.output / "same.png").write_bytes(png_bytes())
+        workflow = {"1": {"class_type": "LoadImage", "inputs": {"image": "output/same.png"}}}
+        packed = await media.prepare_images(workflow)
+        self.assertEqual(base64.b64decode(packed[0]["image"]), payload)
+
+    async def test_rejects_unknown_root_annotation(self):
+        (self.paths.input / "cat.png").write_bytes(png_bytes())
+        workflow = {"1": {"class_type": "LoadImage", "inputs": {"image": "cat.png [abc123]"}}}
+        with self.assertRaisesRegex(media.ServerlessMediaError, "annotation"):
+            await media.prepare_images(workflow)
+
+    async def test_recognizes_custom_file_image_reference(self):
+        (self.paths.input / "source.bmp").write_bytes(png_bytes())
+        workflow = {"1": {"class_type": "CustomImageLoader", "inputs": {"file": "source.bmp"}}}
+
+        packed = await media.prepare_images(workflow)
+
+        self.assertEqual(len(packed), 1)
+        self.assertEqual(workflow["1"]["inputs"]["file"], packed[0]["name"])
+
+    async def test_rejects_missing_and_dynamic_loadimage_values(self):
+        cases = (
+            {"1": {"class_type": "LoadImage", "inputs": {}}},
+            {"1": {"class_type": "LoadImage"}},
+            {"1": {"class_type": "LoadImage", "inputs": None}},
+            {"1": {"class_type": "LoadImage", "inputs": {"image": ["2", 0]}}},
+        )
+        for workflow in cases:
+            with self.subTest(workflow=workflow):
+                with self.assertRaisesRegex(media.ServerlessMediaError, "LoadImage"):
+                    await media.prepare_images(workflow)
+
+    async def test_rejects_missing_source_and_unapproved_extension(self):
+        for value in ("absent.png", "animation.gif", "clip.mp4"):
+            with self.subTest(value=value):
+                workflow = {"1": {"class_type": "LoadImage", "inputs": {"image": value}}}
+                with self.assertRaises(media.ServerlessMediaError):
+                    await media.prepare_images(workflow)
+
+    async def test_rejects_unsupported_audio_or_video_references_without_reading(self):
+        for key, value in (("audio", "private.wav"), ("video", "private.mp4"), ("file", "private.wav")):
+            with self.subTest(key=key):
+                workflow = {"1": {"class_type": "CustomLoader", "inputs": {key: value}}}
+                with self.assertRaisesRegex(media.ServerlessMediaError, "audio|video|media"):
+                    await media.prepare_images(workflow)
+
+    async def test_rejects_parent_traversal_and_absolute_outside_roots(self):
+        outside = Path(self.tempdir.name).parent / "outside.png"
+        outside.write_bytes(png_bytes())
+        self.addCleanup(lambda: outside.unlink(missing_ok=True))
+        for value in ("../outside.png", str(outside)):
+            with self.subTest(value=value):
+                workflow = {"1": {"class_type": "LoadImage", "inputs": {"image": value}}}
+                with self.assertRaises(media.ServerlessMediaError):
+                    await media.prepare_images(workflow)
+
+    async def test_rejects_symlink_escape_from_allowed_root(self):
+        outside = Path(self.tempdir.name).parent / "linked-outside.png"
+        outside.write_bytes(png_bytes())
+        self.addCleanup(lambda: outside.unlink(missing_ok=True))
+        (self.paths.input / "link.png").symlink_to(outside)
+        workflow = {"1": {"class_type": "LoadImage", "inputs": {"image": "link.png"}}}
+
+        with self.assertRaises(media.ServerlessMediaError):
+            await media.prepare_images(workflow)
+
+    async def test_rejects_individual_and_aggregate_input_size_overages(self):
+        huge = self.paths.input / "large.jpg"
+        with huge.open("wb") as handle:
+            handle.truncate(media.MAX_INPUT_IMAGE_BYTES + 1)
+        workflow = {"1": {"class_type": "LoadImage", "inputs": {"image": "large.jpg"}}}
+        with self.assertRaisesRegex(media.ServerlessMediaError, "size"):
+            await media.prepare_images(workflow)
+
+        huge.unlink()
+        first = self.paths.input / "first.png"
+        second = self.paths.input / "second.png"
+        first.write_bytes(b"a" * (media.MAX_INPUT_TOTAL_BYTES // 2 + 1))
+        second.write_bytes(b"b" * (media.MAX_INPUT_TOTAL_BYTES // 2 + 1))
+        workflow = {
+            "1": {"class_type": "LoadImage", "inputs": {"image": "first.png"}},
+            "2": {"class_type": "LoadImage", "inputs": {"image": "second.png"}},
+        }
+        with self.assertRaisesRegex(media.ServerlessMediaError, "size"):
+            await media.prepare_images(workflow)
+
+
+    async def test_accepts_raw_image_over_old_7mib_when_complete_request_fits_10mb(self):
+        raw_size = 7 * 1024 * 1024 + 1
+        source = self.paths.input / "large-input.png"
+        source.write_bytes(b"x" * raw_size)
+        workflow = {"1": {"class_type": "LoadImage", "inputs": {"image": "large-input.png"}}}
+
+        packed = await media.prepare_images(workflow)
+        request_body = runpod.serialize_request(workflow, packed, 30)
+
+        self.assertGreater(raw_size, 7 * 1024 * 1024)
+        self.assertEqual(len(base64.b64decode(packed[0]["image"])), raw_size)
+        self.assertLessEqual(len(request_body), 10_000_000)
+
+
+class ServerlessMediaOutputTests(unittest.IsolatedAsyncioTestCase):
+    def manifest(self, prefix="render"):
+        return [{"collector_id": "collector-1", "job_id": "job-1", "node_id": "12", "kind": "image", "prefix": prefix}]
+
+    def artifact(self, filename, payload=None, **extra):
+        entry = {
+            "filename": filename,
+            "artifact_type": "output",
+            "artifact_path": f"/safe/output/{filename}",
+            "subfolder": "",
+            "type": "base64",
+            "data": base64.b64encode(payload if payload is not None else png_bytes()).decode("ascii"),
+        }
+        entry.update(extra)
+        return entry
+
+    async def test_decodes_rgb_to_normalized_float32_and_orders_by_counter(self):
+        output = {"images": [self.artifact("render_00009_.png"), self.artifact("render_00002_.png")]}
+
+        result = await media.collect_images(output, self.manifest())
+
+        self.assertEqual(list(result), ["job-1"])
+        self.assertEqual(len(result["job-1"]), 2)
+        self.assertTrue(all(image.dtype.name == "float32" for image in result["job-1"]))
+        self.assertEqual(result["job-1"][0].shape, (1, 2, 3))
+        self.assertAlmostEqual(float(result["job-1"][0][0, 0, 0]), 10 / 255)
+
+    async def test_groups_images_under_manifest_job_ids(self):
+        manifest = [
+            self.manifest("first")[0],
+            {"collector_id": "collector-2", "job_id": "job-2", "node_id": "14", "kind": "image", "prefix": "second"},
+        ]
+        output = {"images": [self.artifact("first_00001_.png"), self.artifact("second_00001_.png")]}
+
+        result = await media.collect_images(output, manifest)
+
+        self.assertEqual(set(result), {"job-1", "job-2"})
+        self.assertEqual(len(result["job-1"]), 1)
+        self.assertEqual(len(result["job-2"]), 1)
+
+    async def test_preserves_rgba_alpha(self):
+        output = {"images": [self.artifact("render_00001_.png", png_bytes(mode="RGBA"))]}
+
+        result = await media.collect_images(output, self.manifest())
+
+        self.assertEqual(result["job-1"][0].shape, (1, 2, 4))
+        self.assertAlmostEqual(float(result["job-1"][0][0, 0, 3]), 40 / 255)
+
+    async def test_signed_url_is_downloaded_only_through_injected_downloader(self):
+        output = {"images": [{
+            "filename": "render_00001_.png", "artifact_type": "output", "type": "gcs_url",
+            "url": "https://storage.example.test/signed",
+        }]}
+        fetch = AsyncMock(return_value=png_bytes())
+
+        result = await media.collect_images(output, self.manifest(), download=fetch)
+
+        self.assertEqual(result["job-1"][0].shape, (1, 2, 3))
+        fetch.assert_awaited_once_with("https://storage.example.test/signed")
+
+    async def test_ignores_unrelated_artifacts_but_requires_every_manifest_collector(self):
+        output = {"images": [
+            self.artifact("preview_00001_.png"),
+            self.artifact("render_00001_.png"),
+            {"filename": "mesh.obj", "type": "url", "url": "not a fetch target"},
+        ]}
+
+        result = await media.collect_images(output, self.manifest())
+
+        self.assertEqual(len(result["job-1"]), 1)
+        with self.assertRaisesRegex(media.ServerlessMediaError, "expected|missing"):
+            await media.collect_images({"images": [self.artifact("preview_00001_.png")]}, self.manifest())
+
+    async def test_accepts_compiler_length_flat_safe_prefix(self):
+        prefix = "serverless_" + "j" * 24 + "_" + "w" * 24 + "_" + "c" * 24 + "_image_" + "a" * 64
+        manifest = self.manifest(prefix)
+        output = {"images": [self.artifact(f"{prefix}_00001_.png")]}
+
+        result = await media.collect_images(output, manifest)
+
+        self.assertEqual(len(result["job-1"]), 1)
+
+    async def test_rejects_duplicate_manifest_prefix_and_unsafe_prefix(self):
+        duplicate = self.manifest() * 2
+        with self.assertRaises(media.ServerlessMediaError):
+            await media.collect_images({"images": []}, duplicate)
+        unsafe = self.manifest("../render")
+        with self.assertRaises(media.ServerlessMediaError):
+            await media.collect_images({"images": []}, unsafe)
+
+    async def test_rejects_duplicate_canonical_artifact_identity(self):
+        item = self.artifact("render_00001_.png")
+        with self.assertRaisesRegex(media.ServerlessMediaError, "[Dd]uplicate"):
+            await media.collect_images({"images": [item, dict(item)]}, self.manifest())
+
+    async def test_rejects_matching_non_output_artifact_and_non_numeric_counter(self):
+        wrong_type = self.artifact("render_00001_.png", artifact_type="temp")
+        with self.assertRaises(media.ServerlessMediaError):
+            await media.collect_images({"images": [wrong_type]}, self.manifest())
+        with self.assertRaises(media.ServerlessMediaError):
+            await media.collect_images({"images": [self.artifact("render_final.png")]}, self.manifest())
+
+    async def test_rejects_provider_errors_even_when_job_completed(self):
+        for output in (
+            {"error": "raw provider secret", "images": []},
+            {"errors": ["raw provider secret"], "images": []},
+            {"status": "COMPLETED", "output": {"error": "raw provider secret", "images": []}},
+        ):
+            with self.subTest(output=output):
+                with self.assertRaises(media.ServerlessMediaError) as ctx:
+                    await media.collect_images(output, self.manifest())
+                self.assertNotIn("raw provider secret", str(ctx.exception))
+
+    async def test_rejects_invalid_base64_and_malformed_image(self):
+        for item in (
+            self.artifact("render_00001_.png", data="!not base64!"),
+            self.artifact("render_00001_.png", data=base64.b64encode(b"not an image").decode()),
+        ):
+            with self.subTest(item=item):
+                with self.assertRaises(media.ServerlessMediaError):
+                    await media.collect_images({"images": [item]}, self.manifest())
+
+    async def test_validates_shape_consistency_within_collector(self):
+        output = {"images": [
+            self.artifact("render_00001_.png", png_bytes(size=(2, 1))),
+            self.artifact("render_00002_.png", png_bytes(size=(3, 1))),
+        ]}
+        with self.assertRaisesRegex(media.ServerlessMediaError, "shape|dimensions"):
+            await media.collect_images(output, self.manifest())
+
+    async def test_bounds_output_file_count_and_bytes(self):
+        too_many = {"images": [{}] * (media.MAX_OUTPUT_FILES + 1)}
+        with self.assertRaisesRegex(media.ServerlessMediaError, "files"):
+            await media.collect_images(too_many, self.manifest())
+
+        with patch.object(media, "MAX_OUTPUT_IMAGE_BYTES", 4):
+            output = {"images": [self.artifact("render_00001_.png", data=base64.b64encode(b"12345").decode())]}
+            with self.assertRaisesRegex(media.ServerlessMediaError, "size"):
+                await media.collect_images(output, self.manifest())
+
+    async def test_aggregate_payload_limit_is_checked_as_artifacts_are_read(self):
+        output = {"images": [
+            self.artifact("render_00001_.png", data=base64.b64encode(b"12").decode()),
+            self.artifact("render_00002_.png", data=base64.b64encode(b"34").decode()),
+        ]}
+        with patch.object(media, "MAX_OUTPUT_TOTAL_BYTES", 3):
+            with self.assertRaisesRegex(media.ServerlessMediaError, "size"):
+                await media.collect_images(output, self.manifest())
+
+    async def test_rejects_non_public_or_non_https_artifact_urls_before_downloading(self):
+        for url in ("http://example.test/a", "https://127.0.0.1/a", "https://user:pass@example.test/a"):
+            with self.subTest(url=url):
+                fetch = AsyncMock(return_value=png_bytes())
+                output = {"images": [{"filename": "render_00001_.png", "type": "url", "url": url}]}
+                with self.assertRaises(media.ServerlessMediaError):
+                    await media.collect_images(output, self.manifest(), download=fetch)
+                fetch.assert_not_awaited()
+
+    async def test_public_resolver_rejects_non_global_dns_answers(self):
+        resolver = media._PublicResolver()
+        resolver._getaddrinfo = AsyncMock(return_value=[(2, 1, 6, "", ("8.8.8.8", 443))])
+        self.assertEqual(len(await resolver.resolve("cdn.example.test", 443)), 1)
+        resolver._getaddrinfo = AsyncMock(return_value=[(2, 1, 6, "", ("10.0.0.5", 443))])
+        with self.assertRaises(OSError):
+            await resolver.resolve("cdn.example.test", 443)
+
+    async def test_default_download_revalidates_redirects_and_disables_environment_proxies(self):
+        class Content:
+            def __init__(self, chunks):
+                self.chunks = iter(chunks)
+            async def iter_chunked(self, _size):
+                for chunk in self.chunks:
+                    yield chunk
+
+        class Response:
+            def __init__(self, status, headers=None, chunks=()):
+                self.status, self.headers = status, headers or {}
+                self.content = Content(chunks)
+            async def __aenter__(self):
+                return self
+            async def __aexit__(self, *_args):
+                return False
+
+        class Session:
+            def __init__(self, responses):
+                self.responses, self.calls = list(responses), []
+            async def __aenter__(self):
+                return self
+            async def __aexit__(self, *_args):
+                return False
+            def get(self, url, **kwargs):
+                self.calls.append((url, kwargs))
+                return self.responses.pop(0)
+
+        session = Session([Response(302, {"Location": "https://cdn.example.test/final"}), Response(200, chunks=[b"abc", b"def"])])
+        with patch.object(media.aiohttp, "ClientSession", return_value=session) as create_session:
+            payload = await media.download_public_artifact("https://storage.example.test/signed")
+
+        self.assertEqual(payload, b"abcdef")
+        self.assertEqual([call[0] for call in session.calls], ["https://storage.example.test/signed", "https://cdn.example.test/final"])
+        self.assertTrue(all(call[1]["allow_redirects"] is False for call in session.calls))
+        self.assertFalse(create_session.call_args.kwargs["trust_env"])
+        self.assertIsInstance(create_session.call_args.kwargs["connector"]._resolver, media._PublicResolver)
+        self.assertNotIn("Authorization", session.calls[0][1].get("headers", {}))
+        await create_session.call_args.kwargs["connector"].close()
+
+        blocked = Session([Response(302, {"Location": "https://127.0.0.1/metadata"})])
+        with patch.object(media.aiohttp, "ClientSession", return_value=blocked) as blocked_session:
+            with self.assertRaises(media.ServerlessMediaError):
+                await media.download_public_artifact("https://storage.example.test/signed")
+        self.assertEqual(len(blocked.calls), 1)
+        await blocked_session.call_args.kwargs["connector"].close()
+
+
+if __name__ == "__main__":
+    unittest.main()

tests/test_serverless_prompt.py

@@ -0,0 +1,392 @@
+import importlib.util
+import json
+import sys
+import types
+from pathlib import Path
+
+import pytest
+
+
+MODULE_PATH = (
+    Path(__file__).resolve().parents[1]
+    / "api"
+    / "orchestration"
+    / "serverless_prompt.py"
+)
+_spec = importlib.util.spec_from_file_location("serverless_prompt_under_test", MODULE_PATH)
+assert _spec is not None and _spec.loader is not None
+_serverless_prompt = importlib.util.module_from_spec(_spec)
+_spec.loader.exec_module(_serverless_prompt)
+compile_serverless_prompt = _serverless_prompt.compile_serverless_prompt
+
+
+def _prepared_prompt():
+    return {
+        "1": {"class_type": "CheckpointLoaderSimple", "inputs": {}, "_meta": {"title": "source"}},
+        "2": {"class_type": "KSampler", "inputs": {"model": ["1", 0], "seed": ["3", 0]}},
+        "3": {
+            "class_type": "DistributedSeed",
+            "inputs": {"seed": 40, "is_worker": True, "worker_id": "worker_0"},
+        },
+        "4": {
+            "class_type": "DistributedCollector",
+            "inputs": {"images": ["2", 0], "multi_job_id": "job/42", "worker_id": "worker_0", "is_worker": True},
+        },
+        "5": {"class_type": "VAEDecode", "inputs": {"samples": ["4", 0]}},
+        "6": {"class_type": "SaveImage", "inputs": {"images": ["5", 0]}},
+        "7": {"class_type": "PreviewImage", "inputs": {"images": ["4", 0]}, "_meta": {"title": "Preview Image (auto-added)"}},
+        "8": {"class_type": "UnrelatedNode", "inputs": {}},
+    }
+
+
+def _run(prompt):
+    return compile_serverless_prompt(prompt)
+
+
+def _load_prompt_transform():
+    module_path = MODULE_PATH.with_name("prompt_transform.py")
+    package_name = "serverless_prompt_transform_testpkg"
+    root_pkg = types.ModuleType(package_name)
+    root_pkg.__path__ = []
+    sys.modules[package_name] = root_pkg
+    for suffix in ("api", "api.orchestration", "utils"):
+        pkg = types.ModuleType(f"{package_name}.{suffix}")
+        pkg.__path__ = []
+        sys.modules[f"{package_name}.{suffix}"] = pkg
+    logging_module = types.ModuleType(f"{package_name}.utils.logging")
+    setattr(logging_module, "debug_log", lambda *_args, **_kwargs: None)
+    setattr(logging_module, "log", lambda *_args, **_kwargs: None)
+    sys.modules[f"{package_name}.utils.logging"] = logging_module
+    spec = importlib.util.spec_from_file_location(
+        f"{package_name}.api.orchestration.prompt_transform", module_path
+    )
+    assert spec is not None and spec.loader is not None
+    module = importlib.util.module_from_spec(spec)
+    spec.loader.exec_module(module)
+    return module
+
+
+def test_compiles_prompt_prepared_by_existing_worker_helpers():
+    prompt_transform = _load_prompt_transform()
+    original = {
+        "1": {"class_type": "CheckpointLoaderSimple", "inputs": {}},
+        "2": {"class_type": "KSampler", "inputs": {"model": ["1", 0], "seed": ["3", 0]}},
+        "3": {"class_type": "DistributedSeed", "inputs": {"seed": 100}},
+        "4": {"class_type": "DistributedCollector", "inputs": {"images": ["2", 0]}},
+        "5": {"class_type": "SaveImage", "inputs": {"images": ["4", 0]}},
+    }
+    pruned = prompt_transform.prune_prompt_for_worker(original)
+    prompt_index = prompt_transform.PromptIndex(pruned)
+    prepared = prompt_transform.apply_participant_overrides(
+        pruned,
+        participant_id="worker-a",
+        enabled_worker_ids=["worker-a"],
+        job_id_map=prompt_transform.generate_job_id_map(prompt_index, "run"),
+        master_url="http://master.invalid",
+        delegate_master=False,
+        prompt_index=prompt_index,
+    )
+
+    graph, manifest = _run(prepared)
+
+    assert graph["2"]["inputs"]["seed"] == 101
+    assert set(graph) == {"1", "2", "7"}
+    assert graph["7"]["class_type"] == "SaveImage"
+    assert manifest[0]["job_id"] == "run_4"
+    assert manifest[0]["collector_id"] == "4"
+
+
+def test_compiles_collector_input_to_flat_saveimage_and_prunes_downstream():
+    original = _prepared_prompt()
+
+    graph, manifest = _run(original)
+
+    assert manifest == [
+        {
+            "collector_id": "4",
+            "job_id": "job/42",
+            "node_id": "9",
+            "kind": "image",
+            "prefix": graph["9"]["inputs"]["filename_prefix"],
+        }
+    ]
+    prefix = manifest[0]["prefix"]
+    assert graph["9"] == {
+        "class_type": "SaveImage",
+        "inputs": {"images": ["2", 0], "filename_prefix": prefix},
+        "_meta": {"title": "Serverless output: collector 4 (image)"},
+    }
+    assert "/" not in prefix and "\\" not in prefix
+    assert graph["2"]["inputs"]["seed"] == 41
+    assert set(graph) == {"1", "2", "9"}
+    assert all("Distributed" not in node["class_type"] for node in graph.values())
+    assert original["3"]["inputs"]["seed"] == 40
+    assert original["4"]["inputs"]["images"] == ["2", 0]
+
+
+def test_manifest_and_prefix_are_repeatable_and_safe_for_untrusted_identity_parts():
+    prompt = _prepared_prompt()
+    prompt["4"]["inputs"].update(multi_job_id="../run/a", worker_id="worker/unsafe")
+
+    first_graph, first_manifest = _run(prompt)
+    second_graph, second_manifest = _run(prompt)
+
+    assert first_manifest == second_manifest
+    assert first_graph == second_graph
+    prefix = first_manifest[0]["prefix"]
+    assert prefix == first_graph[first_manifest[0]["node_id"]]["inputs"]["filename_prefix"]
+    assert not any(char in prefix for char in ("/", "\\", ":"))
+    assert first_manifest[0]["job_id"] == "../run/a"
+
+
+def test_compiles_multiple_disconnected_collectors_in_stable_order():
+    prompt = {
+        "10": {"class_type": "LoadImage", "inputs": {}},
+        "20": {"class_type": "LoadImage", "inputs": {}},
+        "2": {"class_type": "DistributedCollector", "inputs": {"images": ["20", 0], "multi_job_id": "b", "worker_id": "worker_1"}},
+        "1": {"class_type": "DistributedCollector", "inputs": {"images": ["10", 0], "multi_job_id": "a", "worker_id": "worker_0"}},
+        "30": {"class_type": "PreviewImage", "inputs": {"images": ["1", 0]}},
+    }
+
+    graph, manifest = _run(prompt)
+
+    assert [item["collector_id"] for item in manifest] == ["1", "2"]
+    assert [item["node_id"] for item in manifest] == ["31", "32"]
+    assert graph["31"]["inputs"]["images"] == ["10", 0]
+    assert graph["32"]["inputs"]["images"] == ["20", 0]
+    assert set(graph) == {"10", "20", "31", "32"}
+
+
+def test_rejects_audio_input_instead_of_emitting_audio_saver():
+    prompt = {
+        "1": {"class_type": "LoadAudio", "inputs": {}},
+        "2": {"class_type": "DistributedCollector", "inputs": {"audio": ["1", 0]}},
+    }
+
+    with pytest.raises(ValueError, match="audio.*unsupported"):
+        _run(prompt)
+
+
+def test_rejects_collector_without_image_input():
+    with pytest.raises(ValueError, match="collector.*image"):
+        _run({"1": {"class_type": "DistributedCollector", "inputs": {}}})
+
+
+@pytest.mark.parametrize(
+    "class_type",
+    ["UltimateSDUpscaleDistributed", "DistributedEmptyImage", "ImageBatchDivider", "AudioBatchDivider"],
+)
+def test_rejects_unsupported_distributed_and_batch_nodes(class_type):
+    prompt = {
+        "1": {"class_type": class_type, "inputs": {}},
+        "2": {"class_type": "DistributedCollector", "inputs": {"images": ["3", 0]}},
+        "3": {"class_type": "LoadImage", "inputs": {}},
+    }
+
+    with pytest.raises(ValueError, match="unsupported"):
+        _run(prompt)
+
+
+def test_rejects_collector_to_collector_dependency_through_processing_node():
+    prompt = {
+        "1": {"class_type": "LoadImage", "inputs": {}},
+        "2": {"class_type": "DistributedCollector", "inputs": {"images": ["1", 0]}},
+        "3": {"class_type": "ImageScale", "inputs": {"image": ["2", 0]}},
+        "4": {"class_type": "DistributedCollector", "inputs": {"images": ["3", 0]}},
+    }
+
+    with pytest.raises(ValueError, match="collector-to-collector"):
+        _run(prompt)
+
+
+@pytest.mark.parametrize(
+    "link",
+    [["missing", 0], ["1", -1], ["1", "0"], ["1", True]],
+)
+def test_rejects_malformed_api_links(link):
+    prompt = {
+        "1": {"class_type": "LoadImage", "inputs": {}},
+        "2": {"class_type": "DistributedCollector", "inputs": {"images": link}},
+    }
+
+    with pytest.raises(ValueError, match="link"):
+        _run(prompt)
+
+
+def test_rejects_unexpected_output_slot_from_removed_distributed_node():
+    prompt = {
+        "1": {"class_type": "DistributedSeed", "inputs": {"seed": 1}},
+        "2": {"class_type": "KSampler", "inputs": {"seed": ["1", 1]}},
+        "3": {"class_type": "DistributedCollector", "inputs": {"images": ["2", 0]}},
+    }
+
+    with pytest.raises(ValueError, match="output slot"):
+        _run(prompt)
+
+
+def test_distributed_seed_matches_worker_offset_and_master_passthrough():
+    prompt = {
+        "1": {"class_type": "DistributedSeed", "inputs": {"seed": 10, "is_worker": True, "worker_id": "worker_1"}},
+        "2": {"class_type": "DistributedSeed", "inputs": {"seed": 7, "is_worker": False}},
+        "3": {"class_type": "KSampler", "inputs": {"seed": ["1", 0], "steps": ["2", 0]}},
+        "4": {"class_type": "DistributedCollector", "inputs": {"images": ["3", 0]}},
+    }
+
+    graph, _manifest = _run(prompt)
+
+    assert graph["3"]["inputs"] == {"seed": 12, "steps": 7}
+    assert "1" not in graph and "2" not in graph
+
+
+def test_distributed_value_uses_one_based_worker_values_and_type_coercion():
+    prompt = {
+        "1": {"class_type": "DistributedValue", "inputs": {"default_value": "3.9", "worker_values": json.dumps({"_type": "INT", "1": "8.7"}), "is_worker": True, "worker_id": "worker_0"}},
+        "2": {"class_type": "DistributedValue", "inputs": {"default_value": "3.9", "worker_values": json.dumps({"_type": "INT", "2": ""}), "is_worker": True, "worker_id": "worker_1"}},
+        "3": {"class_type": "KSampler", "inputs": {"steps": ["1", 0], "seed": ["2", 0]}},
+        "4": {"class_type": "DistributedCollector", "inputs": {"images": ["3", 0]}},
+    }
+
+    graph, _manifest = _run(prompt)
+
+    assert graph["3"]["inputs"] == {"steps": 8, "seed": 3}
+    assert "1" not in graph and "2" not in graph
+
+
+def test_resolves_stock_primitive_links_for_distributed_seed_and_value():
+    prompt = {
+        "1": {"class_type": "PrimitiveInt", "inputs": {"value": 25}},
+        "2": {"class_type": "DistributedSeed", "inputs": {"seed": ["1", 0], "is_worker": True, "worker_id": "worker_0"}},
+        "3": {"class_type": "PrimitiveString", "inputs": {"value": "4.8"}},
+        "4": {"class_type": "PrimitiveString", "inputs": {"value": '{"_type":"FLOAT","1":"2.75"}'}},
+        "5": {"class_type": "DistributedValue", "inputs": {"default_value": ["3", 0], "worker_values": ["4", 0], "is_worker": True, "worker_id": "worker_0"}},
+        "6": {"class_type": "KSampler", "inputs": {"seed": ["2", 0], "cfg": ["5", 0]}},
+        "7": {"class_type": "DistributedCollector", "inputs": {"images": ["6", 0]}},
+    }
+
+    graph, _manifest = _run(prompt)
+
+    assert graph["6"]["inputs"] == {"seed": 26, "cfg": 2.75}
+    assert not {"1", "2", "3", "4", "5"}.intersection(graph)
+
+
+def test_rejects_dynamic_linked_seed_or_value_without_executing_it():
+    prompt = {
+        "1": {"class_type": "ArbitraryNode", "inputs": {}},
+        "2": {"class_type": "DistributedSeed", "inputs": {"seed": ["1", 0], "is_worker": True, "worker_id": "worker_0"}},
+        "3": {"class_type": "KSampler", "inputs": {"seed": ["2", 0]}},
+        "4": {"class_type": "DistributedCollector", "inputs": {"images": ["3", 0]}},
+    }
+
+    with pytest.raises(ValueError, match="literal or supported Primitive"):
+        _run(prompt)
+
+
+def test_primitive_resolution_detects_cycles():
+    prompt = {
+        "1": {"class_type": "PrimitiveInt", "inputs": {"value": ["2", 0]}},
+        "2": {"class_type": "PrimitiveInt", "inputs": {"value": ["1", 0]}},
+        "3": {"class_type": "DistributedSeed", "inputs": {"seed": ["1", 0]}},
+        "4": {"class_type": "KSampler", "inputs": {"seed": ["3", 0]}},
+        "5": {"class_type": "DistributedCollector", "inputs": {"images": ["4", 0]}},
+    }
+
+    with pytest.raises(ValueError, match="cycle"):
+        _run(prompt)
+
+
+def test_model_name_trivial_text_passthrough_is_inlined():
+    prompt = {
+        "1": {"class_type": "DistributedModelName", "inputs": {"text": "model.safetensors"}},
+        "2": {"class_type": "KSampler", "inputs": {"model_name": ["1", 0]}},
+        "3": {"class_type": "DistributedCollector", "inputs": {"images": ["2", 0]}},
+    }
+
+    graph, _manifest = _run(prompt)
+
+    assert graph["2"]["inputs"]["model_name"] == "model.safetensors"
+    assert "1" not in graph
+
+
+def test_rejects_dynamic_linked_model_name_text():
+    prompt = {
+        "1": {"class_type": "ArbitraryNode", "inputs": {}},
+        "2": {"class_type": "DistributedModelName", "inputs": {"text": ["1", 0]}},
+        "3": {"class_type": "KSampler", "inputs": {"model_name": ["2", 0]}},
+        "4": {"class_type": "DistributedCollector", "inputs": {"images": ["3", 0]}},
+    }
+
+    with pytest.raises(ValueError, match="DistributedModelName.*literal or supported Primitive"):
+        _run(prompt)
+
+
+def test_resolves_boolean_and_float_primitive_links():
+    prompt = {
+        "1": {"class_type": "PrimitiveBoolean", "inputs": {"value": True}},
+        "2": {"class_type": "PrimitiveFloat", "inputs": {"value": 1.25}},
+        "3": {"class_type": "DistributedValue", "inputs": {"default_value": ["1", 0], "is_worker": False}},
+        "4": {"class_type": "DistributedValue", "inputs": {"default_value": ["2", 0], "worker_values": '{"_type":"FLOAT","1":"2.5"}', "is_worker": True, "worker_id": "worker_0"}},
+        "5": {"class_type": "KSampler", "inputs": {"enabled": ["3", 0], "cfg": ["4", 0]}},
+        "6": {"class_type": "DistributedCollector", "inputs": {"images": ["5", 0]}},
+    }
+
+    graph, _manifest = _run(prompt)
+
+    assert graph["5"]["inputs"] == {"enabled": True, "cfg": 2.5}
+    assert not {"1", "2", "3", "4"}.intersection(graph)
+
+
+def test_compiled_graph_matches_golden_prompt_and_manifest():
+    prompt = _prepared_prompt()
+    prompt["3"]["inputs"]["seed"] = ["10", 0]
+    prompt["10"] = {"class_type": "PrimitiveInt", "inputs": {"value": 40}}
+    prompt["11"] = {"class_type": "PrimitiveFloat", "inputs": {"value": 1.25}}
+    prompt["12"] = {
+        "class_type": "DistributedValue",
+        "inputs": {
+            "default_value": ["11", 0],
+            "worker_values": json.dumps({"_type": "FLOAT", "1": "2.5"}),
+            "is_worker": True,
+            "worker_id": "worker_0",
+        },
+    }
+    prompt["13"] = {"class_type": "PrimitiveString", "inputs": {"value": "model.safetensors"}}
+    prompt["14"] = {"class_type": "DistributedModelName", "inputs": {"text": ["13", 0]}}
+    prompt["2"]["inputs"].update(cfg=["12", 0], model_name=["14", 0])
+
+    graph, manifest = _run(prompt)
+
+    expected_prefix = (
+        "serverless_job_42_worker_0_4_image_"
+        "1c81da108a2eb60282bd436512acfc59903aba73e49b19b6f47bbdcafd30d244"
+    )
+    assert list(graph) == ["1", "2", "15"]
+    assert graph == {
+        "1": {
+            "class_type": "CheckpointLoaderSimple",
+            "inputs": {},
+            "_meta": {"title": "source"},
+        },
+        "2": {
+            "class_type": "KSampler",
+            "inputs": {
+                "model": ["1", 0],
+                "seed": 41,
+                "cfg": 2.5,
+                "model_name": "model.safetensors",
+            },
+        },
+        "15": {
+            "class_type": "SaveImage",
+            "inputs": {"images": ["2", 0], "filename_prefix": expected_prefix},
+            "_meta": {"title": "Serverless output: collector 4 (image)"},
+        },
+    }
+    assert manifest == [
+        {
+            "collector_id": "4",
+            "job_id": "job/42",
+            "node_id": "15",
+            "kind": "image",
+            "prefix": expected_prefix,
+        }
+    ]

tests/test_serverless_routes.py

@@ -0,0 +1,624 @@
+import copy
+import importlib.util
+import json
+import sys
+import tempfile
+import types
+import unittest
+from pathlib import Path
+from unittest.mock import patch
+
+
+class _FakeResponse:
+    def __init__(self, payload, status=200):
+        self.payload = copy.deepcopy(payload)
+        self.status = status
+
+
+class _FakeRequest:
+    def __init__(self, payload=None, error=None):
+        self.payload = payload
+        self.error = error
+
+    async def json(self):
+        if self.error is not None:
+            raise self.error
+        return self.payload
+
+
+class _Routes:
+    def get(self, _path):
+        return lambda handler: handler
+
+    def post(self, _path):
+        return lambda handler: handler
+
+
+def _load_modules():
+    repo = Path(__file__).resolve().parents[1]
+    package_name = "dist_serverless_routes_testpkg"
+    for name in list(sys.modules):
+        if name == package_name or name.startswith(f"{package_name}."):
+            del sys.modules[name]
+
+    root = types.ModuleType(package_name)
+    root.__path__ = [str(repo)]
+    sys.modules[package_name] = root
+    api_pkg = types.ModuleType(f"{package_name}.api")
+    api_pkg.__path__ = [str(repo / "api")]
+    sys.modules[f"{package_name}.api"] = api_pkg
+    utils_pkg = types.ModuleType(f"{package_name}.utils")
+    utils_pkg.__path__ = [str(repo / "utils")]
+    sys.modules[f"{package_name}.utils"] = utils_pkg
+    orchestration_pkg = types.ModuleType(f"{package_name}.api.orchestration")
+    orchestration_pkg.__path__ = [str(repo / "api" / "orchestration")]
+    sys.modules[f"{package_name}.api.orchestration"] = orchestration_pkg
+
+    logging_module = types.ModuleType(f"{package_name}.utils.logging")
+    logging_module.log = lambda *_args, **_kwargs: None
+    logging_module.debug_log = lambda *_args, **_kwargs: None
+    sys.modules[logging_module.__name__] = logging_module
+    constants_module = types.ModuleType(f"{package_name}.utils.constants")
+    constants_module.HEARTBEAT_TIMEOUT = 30
+    sys.modules[constants_module.__name__] = constants_module
+
+    def load_file(module_name, path):
+        spec = importlib.util.spec_from_file_location(module_name, path)
+        assert spec is not None and spec.loader is not None
+        module = importlib.util.module_from_spec(spec)
+        sys.modules[module_name] = module
+        spec.loader.exec_module(module)
+        return module
+
+    config_module = load_file(f"{package_name}.utils.config", repo / "utils" / "config.py")
+    serverless_config = load_file(
+        f"{package_name}.utils.serverless_config", repo / "utils" / "serverless_config.py"
+    )
+
+    runtime = types.ModuleType(f"{package_name}.api.orchestration.serverless_runtime")
+    runtime.secret_store = None
+    runtime.manager = types.SimpleNamespace(tasks={}, runs={}, pool_is_active=lambda _: False)
+    runtime.get_secret_store = lambda: runtime.secret_store
+    runtime.get_manager = lambda: runtime.manager
+    sys.modules[runtime.__name__] = runtime
+
+    import aiohttp  # Ensure the real dependency is loaded; never replace global aiohttp.
+    previous_server = sys.modules.get("server")
+    server = types.ModuleType("server")
+    server.PromptServer = types.SimpleNamespace(instance=types.SimpleNamespace(routes=_Routes()))
+    sys.modules["server"] = server
+
+    network = types.ModuleType(f"{package_name}.utils.network")
+
+    async def handle_api_error(_request, error, status=500):
+        return _FakeResponse({"status": "error", "message": str(error)}, status)
+
+    network.handle_api_error = handle_api_error
+    network.normalize_host = lambda value: value
+    sys.modules[network.__name__] = network
+
+    routes = load_file(f"{package_name}.api.config_routes", repo / "api" / "config_routes.py")
+    routes.web = types.SimpleNamespace(
+        json_response=lambda payload, status=200: _FakeResponse(payload, status)
+    )
+
+    if previous_server is None:
+        sys.modules.pop("server", None)
+    else:
+        sys.modules["server"] = previous_server
+    return config_module, serverless_config, runtime, routes
+
+
+config_module, serverless_config, runtime_module, config_routes = _load_modules()
+
+
+class _RunningTask:
+    def done(self):
+        return False
+
+
+class _ConfigRouteFixture(unittest.IsolatedAsyncioTestCase):
+    def setUp(self):
+        self.tempdir = tempfile.TemporaryDirectory()
+        self.root = Path(self.tempdir.name)
+        config_module.CONFIG_FILE = str(self.root / "gpu_config.json")
+        config_module.invalidate_config_cache()
+        self.config = config_module.get_default_config()
+        self.config["workers"] = []
+        self.assertTrue(config_module.save_config(self.config))
+        self.secrets = serverless_config.SecretStore(self.root / "private" / "credentials.json")
+        runtime_module.secret_store = self.secrets
+        runtime_module.manager = types.SimpleNamespace(tasks={}, runs={}, pool_is_active=lambda _: False)
+
+    def tearDown(self):
+        config_module.invalidate_config_cache()
+        self.tempdir.cleanup()
+
+    def read_config_file(self):
+        return json.loads(Path(config_module.CONFIG_FILE).read_text(encoding="utf-8"))
+
+
+class ServerlessConfigRouteTests(_ConfigRouteFixture):
+    async def test_get_config_redacts_keys_and_reports_only_configured_boolean(self):
+        self.secrets.set("pool-1", "private-api-key")
+        self.config["workers"] = [
+            {"id": "pool-1", "type": "serverless", "provider": "runpod", "endpoint_id": "ep-1",
+             "api_key": "inline-api-key", "name": "GPU"}
+        ]
+        Path(config_module.CONFIG_FILE).write_text(json.dumps(self.config), encoding="utf-8")
+        config_module.invalidate_config_cache()
+
+        response = await config_routes.get_config_endpoint(_FakeRequest())
+
+        self.assertEqual(response.status, 200)
+        worker = response.payload["workers"][0]
+        self.assertTrue(worker["api_key_configured"])
+        self.assertNotIn("api_key", worker)
+        self.assertNotIn("private-api-key", json.dumps(response.payload))
+        self.assertNotIn("inline-api-key", json.dumps(response.payload))
+
+    async def test_get_config_redacts_normalized_secret_field_aliases(self):
+        aliases = {
+            "apiKey": "camel-api-key",
+            "APIKEY": "upper-api-key",
+            "clearApiKey": "camel-clear-key",
+            "CLEAR_API_KEY": "upper-clear-key",
+            "runpod_CREDENTIAL": "provider-credential",
+        }
+        self.config["workers"] = [{
+            "id": "pool-1", "type": "serverless", "endpoint_id": "ep-123",
+            **aliases,
+            "nested": {"credential_note": "nested-credential"},
+        }]
+        Path(config_module.CONFIG_FILE).write_text(json.dumps(self.config), encoding="utf-8")
+        config_module.invalidate_config_cache()
+
+        response = await config_routes.get_config_endpoint(_FakeRequest())
+
+        self.assertEqual(response.status, 200)
+        worker = response.payload["workers"][0]
+        for alias, value in aliases.items():
+            self.assertNotIn(alias, worker)
+            self.assertNotIn(value, json.dumps(response.payload))
+        self.assertNotIn("credential_note", worker["nested"])
+        self.assertNotIn("nested-credential", json.dumps(response.payload))
+
+    async def test_bulk_config_rejects_normalized_secret_field_aliases(self):
+        for secret_field in ("apiKey", "APIKEY", "clearApiKey", "RUNPOD_CREDENTIAL"):
+            with self.subTest(secret_field=secret_field):
+                secret = f"private-{secret_field}"
+                response = await config_routes.update_config_endpoint(_FakeRequest({
+                    "workers": [{"id": "pool-1", "type": "local", secret_field: secret}]
+                }))
+                self.assertEqual(response.status, 400)
+                self.assertNotIn(secret, json.dumps(response.payload))
+        self.assertEqual(self.read_config_file()["workers"], [])
+
+    async def test_create_serverless_worker_without_local_fields_and_store_key_privately(self):
+        secret = "runpod-secret-never-returned"
+        payload = {
+            "worker_id": "pool-1", "name": "GPU pool", "type": "serverless", "provider": "runpod",
+            "endpoint_id": "ep-123", "jobs_per_run": 3, "concurrency": 2,
+            "timeout_seconds": 600, "enabled": True, "api_key": secret,
+        }
+
+        response = await config_routes.update_worker_endpoint(_FakeRequest(payload))
+
+        self.assertEqual(response.status, 200)
+        self.assertTrue(response.payload["api_key_configured"])
+        self.assertNotIn(secret, json.dumps(response.payload))
+        saved = self.read_config_file()["workers"][0]
+        self.assertEqual(saved["endpoint_id"], "ep-123")
+        self.assertEqual(saved["jobs_per_run"], 3)
+        # Legacy field from older browser tabs is accepted but not persisted.
+        self.assertNotIn("concurrency", saved)
+        self.assertEqual(saved["timeout_seconds"], 600)
+        for obsolete in ("host", "port", "cuda_device", "extra_args", "api_key", "clear_api_key"):
+            self.assertNotIn(obsolete, saved)
+        self.assertEqual(self.secrets.get("pool-1"), secret)
+
+    async def test_enable_only_update_preserves_serverless_settings_and_saved_key(self):
+        self.secrets.set("pool-1", "saved-secret")
+        self.config["workers"] = [{
+            "id": "pool-1", "type": "serverless", "provider": "runpod", "name": "Pool",
+            "endpoint_id": "ep-123", "jobs_per_run": 4, "concurrency": 3,
+            "timeout_seconds": 900, "enabled": False,
+        }]
+        self.assertTrue(config_module.save_config(self.config))
+
+        response = await config_routes.update_worker_endpoint(
+            _FakeRequest({"worker_id": "pool-1", "enabled": True})
+        )
+
+        worker = self.read_config_file()["workers"][0]
+        self.assertTrue(worker["enabled"])
+        self.assertEqual(worker["endpoint_id"], "ep-123")
+        self.assertEqual(worker["jobs_per_run"], 4)
+        self.assertNotIn("concurrency", worker)
+        self.assertEqual(worker["timeout_seconds"], 900)
+        self.assertEqual(self.secrets.get("pool-1"), "saved-secret")
+        self.assertTrue(response.payload["api_key_configured"])
+
+    async def test_invalid_serverless_record_is_not_persisted_or_secret_written(self):
+        secret = "must-not-leak"
+        response = await config_routes.update_worker_endpoint(_FakeRequest({
+            "worker_id": "pool-1", "type": "serverless", "provider": "runpod",
+            "endpoint_id": "ep-123", "jobs_per_run": True, "api_key": secret,
+        }))
+
+        self.assertEqual(response.status, 400)
+        self.assertNotIn(secret, json.dumps(response.payload))
+        self.assertEqual(self.read_config_file()["workers"], [])
+        self.assertIsNone(self.secrets.get("pool-1"))
+
+    async def test_json_decode_error_is_generic_and_does_not_echo_body(self):
+        secret = "body-secret-value"
+        response = await config_routes.update_worker_endpoint(
+            _FakeRequest(error=ValueError(f"bad json near {secret}"))
+        )
+        self.assertEqual(response.status, 400)
+        self.assertNotIn(secret, json.dumps(response.payload))
+
+    async def test_bulk_config_rejects_api_keys_at_any_depth_without_persisting(self):
+        secret = "bulk-secret-never-write"
+        response = await config_routes.update_config_endpoint(_FakeRequest({
+            "workers": [{
+                "id": "pool-1", "type": "serverless", "provider": "runpod",
+                "endpoint_id": "ep-123", "nested": {"api_key": secret},
+            }]
+        }))
+
+        self.assertEqual(response.status, 400)
+        self.assertNotIn(secret, json.dumps(response.payload))
+        self.assertEqual(self.read_config_file()["workers"], [])
+        self.assertFalse(self.secrets.path.exists())
+
+    async def test_bulk_update_validates_and_returns_redacted_serverless_config(self):
+        self.secrets.set("pool-1", "saved-secret")
+        response = await config_routes.update_config_endpoint(_FakeRequest({
+            "workers": [{
+                "id": "pool-1", "type": "serverless", "provider": "runpod",
+                "endpoint_id": "ep-123", "name": "Pool", "enabled": True,
+                "host": "obsolete-host", "port": 8188, "cuda_device": 0,
+            }]
+        }))
+
+        self.assertEqual(response.status, 200)
+        self.assertTrue(response.payload["config"]["workers"][0]["api_key_configured"])
+        saved = self.read_config_file()["workers"][0]
+        for obsolete in ("host", "port", "cuda_device"):
+            self.assertNotIn(obsolete, saved)
+        self.assertNotIn("api_key", response.payload["config"]["workers"][0])
+        self.assertEqual(self.secrets.get("pool-1"), "saved-secret")
+
+    async def test_bulk_type_conversion_clears_secret_and_serverless_fields(self):
+        self.secrets.set("pool-1", "bulk-clear-key")
+        self.config["workers"] = [{
+            "id": "pool-1", "type": "serverless", "provider": "runpod", "endpoint_id": "ep-123",
+        }]
+        self.assertTrue(config_module.save_config(self.config))
+
+        response = await config_routes.update_config_endpoint(_FakeRequest({
+            "workers": [{
+                "id": "pool-1", "type": "local", "port": 8188,
+                "provider": "runpod", "endpoint_id": "legacy-ep", "api_key_configured": True,
+            }]
+        }))
+
+        self.assertEqual(response.status, 200)
+        self.assertIsNone(self.secrets.get("pool-1"))
+        saved = self.read_config_file()["workers"][0]
+        for field in ("provider", "endpoint_id", "api_key_configured"):
+            self.assertNotIn(field, saved)
+
+    async def test_bulk_invalid_serverless_record_does_not_replace_configuration(self):
+        existing = {"id": "local-1", "type": "local", "port": 8188}
+        self.config["workers"] = [existing]
+        self.assertTrue(config_module.save_config(self.config))
+
+        response = await config_routes.update_config_endpoint(_FakeRequest({
+            "workers": [{"id": "pool-1", "type": "serverless", "endpoint_id": "bad/id"}]
+        }))
+
+        self.assertEqual(response.status, 400)
+        self.assertEqual(self.read_config_file()["workers"], [existing])
+
+    async def test_delete_serverless_worker_clears_saved_key(self):
+        self.secrets.set("pool-1", "delete-me")
+        self.config["workers"] = [{
+            "id": "pool-1", "type": "serverless", "provider": "runpod", "endpoint_id": "ep-123"
+        }]
+        self.assertTrue(config_module.save_config(self.config))
+
+        response = await config_routes.delete_worker_endpoint(_FakeRequest({"worker_id": "pool-1"}))
+
+        self.assertEqual(response.status, 200)
+        self.assertEqual(self.read_config_file()["workers"], [])
+        self.assertIsNone(self.secrets.get("pool-1"))
+
+    async def test_type_conversion_clears_secret_and_removes_serverless_fields(self):
+        self.secrets.set("pool-1", "old-key")
+        self.config["workers"] = [{
+            "id": "pool-1", "name": "Pool", "type": "serverless", "provider": "runpod",
+            "endpoint_id": "ep-123", "jobs_per_run": 2, "concurrency": 2, "timeout_seconds": 600,
+        }]
+        self.assertTrue(config_module.save_config(self.config))
+
+        response = await config_routes.update_worker_endpoint(_FakeRequest({
+            "worker_id": "pool-1", "type": "local", "name": "Local", "port": 8188,
+            "cuda_device": 0, "enabled": False,
+        }))
+
+        self.assertEqual(response.status, 200)
+        self.assertIsNone(self.secrets.get("pool-1"))
+        worker = self.read_config_file()["workers"][0]
+        self.assertEqual(worker["type"], "local")
+        for serverless_field in ("provider", "endpoint_id", "jobs_per_run", "concurrency", "timeout_seconds"):
+            self.assertNotIn(serverless_field, worker)
+
+    async def test_enabled_toggle_allowed_during_active_run_but_endpoint_change_is_rejected(self):
+        self.secrets.set("pool-1", "saved-key")
+        self.config["workers"] = [{
+            "id": "pool-1", "type": "serverless", "provider": "runpod", "endpoint_id": "ep-123",
+            "enabled": False,
+        }]
+        self.assertTrue(config_module.save_config(self.config))
+        runtime_module.manager = types.SimpleNamespace(
+            tasks={"run-1": _RunningTask()},
+            runs={"run-1": {"worker": {"id": "serverless:pool-1:1", "pool_id": "pool-1"}}},
+            pool_is_active=lambda worker_id: worker_id == "pool-1",
+        )
+
+        enabled = await config_routes.update_worker_endpoint(
+            _FakeRequest({"worker_id": "pool-1", "enabled": True})
+        )
+        blocked = await config_routes.update_worker_endpoint(_FakeRequest({
+            "worker_id": "pool-1", "endpoint_id": "ep-456",
+        }))
+
+        self.assertEqual(enabled.status, 200)
+        self.assertEqual(blocked.status, 409)
+        self.assertEqual(self.read_config_file()["workers"][0]["endpoint_id"], "ep-123")
+
+    async def test_blank_api_key_keeps_saved_key_and_clear_api_key_deletes_it(self):
+        self.secrets.set("pool-1", "saved-key")
+        self.config["workers"] = [{
+            "id": "pool-1", "type": "serverless", "provider": "runpod", "endpoint_id": "ep-123",
+        }]
+        self.assertTrue(config_module.save_config(self.config))
+
+        keep = await config_routes.update_worker_endpoint(_FakeRequest({
+            "worker_id": "pool-1", "api_key": "",
+        }))
+        clear = await config_routes.update_worker_endpoint(_FakeRequest({
+            "worker_id": "pool-1", "clear_api_key": True,
+        }))
+
+        self.assertTrue(keep.payload["api_key_configured"])
+        self.assertFalse(clear.payload["api_key_configured"])
+        self.assertIsNone(self.secrets.get("pool-1"))
+
+    async def test_config_save_refuses_inline_api_keys_and_invalid_serverless_records(self):
+        with self.subTest(case="inline key"):
+            config = config_module.get_default_config()
+            config["workers"] = [{"id": "pool-1", "type": "local", "api_key": "private"}]
+            self.assertFalse(config_module.save_config(config))
+        with self.subTest(case="invalid serverless record"):
+            config = config_module.get_default_config()
+            config["workers"] = [{"id": "pool-1", "type": "serverless", "endpoint_id": "bad/id"}]
+            self.assertFalse(config_module.save_config(config))
+
+    async def test_active_pool_blocks_credential_changes_type_conversion_and_deletion(self):
+        self.secrets.set("pool-1", "saved-key")
+        self.config["workers"] = [{
+            "id": "pool-1", "type": "serverless", "provider": "runpod", "endpoint_id": "ep-123",
+        }]
+        self.assertTrue(config_module.save_config(self.config))
+        runtime_module.manager = types.SimpleNamespace(
+            tasks={"run-1": _RunningTask()},
+            runs={"run-1": {"worker": {"id": "serverless:pool-1:1", "pool_id": "pool-1"}}},
+            pool_is_active=lambda worker_id: worker_id == "pool-1",
+        )
+
+        credential_change = await config_routes.update_worker_endpoint(_FakeRequest({
+            "worker_id": "pool-1", "api_key": "new-key",
+        }))
+        type_change = await config_routes.update_worker_endpoint(_FakeRequest({
+            "worker_id": "pool-1", "type": "local", "port": 8188, "cuda_device": 0,
+        }))
+        deletion = await config_routes.delete_worker_endpoint(_FakeRequest({"worker_id": "pool-1"}))
+
+        self.assertEqual(credential_change.status, 409)
+        self.assertEqual(type_change.status, 409)
+        self.assertEqual(deletion.status, 409)
+        self.assertEqual(self.secrets.get("pool-1"), "saved-key")
+        self.assertEqual(self.read_config_file()["workers"][0]["type"], "serverless")
+
+    async def test_secret_write_is_rolled_back_when_config_persistence_fails(self):
+        secret = "write-then-rollback"
+        with patch.object(config_module, "save_config", return_value=False):
+            response = await config_routes.update_worker_endpoint(_FakeRequest({
+                "worker_id": "pool-1", "type": "serverless", "endpoint_id": "ep-123",
+                "api_key": secret,
+            }))
+
+        self.assertEqual(response.status, 500)
+        self.assertIsNone(self.secrets.get("pool-1"))
+        self.assertEqual(self.read_config_file()["workers"], [])
+        self.assertEqual(config_module.load_config()["workers"], [])
+
+    async def test_bulk_secret_delete_is_rolled_back_when_config_persistence_fails(self):
+        self.secrets.set("pool-1", "bulk-restore-key")
+        self.config["workers"] = [{
+            "id": "pool-1", "type": "serverless", "endpoint_id": "ep-123",
+        }]
+        self.assertTrue(config_module.save_config(self.config))
+
+        with patch.object(config_module, "save_config", return_value=False):
+            response = await config_routes.update_config_endpoint(_FakeRequest({
+                "workers": [{"id": "pool-1", "type": "local", "port": 8188}]
+            }))
+
+        self.assertEqual(response.status, 500)
+        self.assertEqual(self.secrets.get("pool-1"), "bulk-restore-key")
+        self.assertEqual(self.read_config_file()["workers"][0]["type"], "serverless")
+
+    async def test_secret_replacement_is_rolled_back_when_config_persistence_fails(self):
+        self.secrets.set("pool-1", "prior-key")
+        self.config["workers"] = [{
+            "id": "pool-1", "type": "serverless", "endpoint_id": "ep-123",
+        }]
+        self.assertTrue(config_module.save_config(self.config))
+
+        with patch.object(config_module, "save_config", return_value=False):
+            response = await config_routes.update_worker_endpoint(_FakeRequest({
+                "worker_id": "pool-1", "api_key": "replacement-key",
+            }))
+
+        self.assertEqual(response.status, 500)
+        self.assertEqual(self.secrets.get("pool-1"), "prior-key")
+        self.assertEqual(self.read_config_file()["workers"][0]["type"], "serverless")
+
+    async def test_delete_secret_is_rolled_back_when_config_persistence_fails(self):
+        self.secrets.set("pool-1", "delete-restore-key")
+        self.config["workers"] = [{
+            "id": "pool-1", "type": "serverless", "endpoint_id": "ep-123",
+        }]
+        self.assertTrue(config_module.save_config(self.config))
+
+        with patch.object(config_module, "save_config", return_value=False):
+            response = await config_routes.delete_worker_endpoint(_FakeRequest({"worker_id": "pool-1"}))
+
+        self.assertEqual(response.status, 500)
+        self.assertEqual(self.secrets.get("pool-1"), "delete-restore-key")
+        self.assertEqual(self.read_config_file()["workers"][0]["id"], "pool-1")
+
+    async def test_regular_worker_delete_does_not_require_posix_secret_storage(self):
+        self.config["workers"] = [{"id": "local-1", "type": "local", "port": 8188}]
+        self.assertTrue(config_module.save_config(self.config))
+        with patch.object(config_routes, "_serverless_secret_store", side_effect=RuntimeError("POSIX only")):
+            response = await config_routes.delete_worker_endpoint(_FakeRequest({"worker_id": "local-1"}))
+        self.assertEqual(response.status, 200)
+        self.assertEqual(self.read_config_file()["workers"], [])
+
+    async def test_enabling_serverless_without_key_is_rejected(self):
+        response = await config_routes.update_worker_endpoint(_FakeRequest({
+            "worker_id": "pool-1", "type": "serverless", "endpoint_id": "ep-123", "enabled": True,
+        }))
+        self.assertEqual(response.status, 400)
+        self.assertEqual(self.read_config_file()["workers"], [])
+
+    async def test_bulk_endpoint_change_is_blocked_during_active_run(self):
+        self.config["workers"] = [{"id": "pool-1", "type": "serverless", "endpoint_id": "ep-123"}]
+        self.assertTrue(config_module.save_config(self.config))
+        runtime_module.manager = types.SimpleNamespace(
+            tasks={"run-1": _RunningTask()},
+            runs={"run-1": {"worker": {"id": "serverless:pool-1:1", "pool_id": "pool-1"}}},
+            pool_is_active=lambda worker_id: worker_id == "pool-1",
+        )
+        updated = copy.deepcopy(self.config["workers"])
+        updated[0]["endpoint_id"] = "ep-other"
+        response = await config_routes.update_config_endpoint(_FakeRequest({"workers": updated}))
+        self.assertEqual(response.status, 409)
+        self.assertEqual(self.read_config_file()["workers"][0]["endpoint_id"], "ep-123")
+
+    async def test_non_serverless_update_behavior_is_preserved(self):
+        self.config["workers"] = [{"id": "local-1", "name": "Local", "type": "local", "port": 8188}]
+        self.assertTrue(config_module.save_config(self.config))
+
+        response = await config_routes.update_worker_endpoint(_FakeRequest({
+            "worker_id": "local-1", "name": "Renamed", "enabled": True,
+        }))
+
+        self.assertEqual(response.status, 200)
+        worker = self.read_config_file()["workers"][0]
+        self.assertEqual(worker["name"], "Renamed")
+        self.assertTrue(worker["enabled"])
+
+    async def test_config_normalization_removes_legacy_local_fields_from_serverless_records(self):
+        raw = {
+            "workers": [{
+                "id": "pool-1", "type": "serverless", "endpoint_id": "ep-123",
+                "host": "localhost", "port": 8188, "cuda_device": 2, "extra_args": "--old",
+            }]
+        }
+        normalized = config_module._merge_with_defaults(raw, config_module.get_default_config())
+        worker = normalized["workers"][0]
+        for obsolete in ("host", "port", "cuda_device", "extra_args"):
+            self.assertNotIn(obsolete, worker)
+
+
+class PersistedPoolGuardTests(_ConfigRouteFixture):
+    """Use the actual manager/ledger across restart, not a mocked idle result."""
+
+    def setUp(self):
+        super().setUp()
+        from test_serverless_runtime import runtime
+        from unittest.mock import AsyncMock
+        self.runtime = runtime
+        self.session_factory = AsyncMock()
+        self.ledger_path = self.root / "jobs.json"
+        self.manager = runtime.ServerlessManager(types.SimpleNamespace(), self.secrets, self.ledger_path, self.session_factory)
+        runtime_module.manager = self.manager
+        self.secrets.set("pool-1", "saved-key")
+        self.config["workers"] = [{"id": "pool-1", "type": "serverless", "endpoint_id": "ep-123", "concurrency": 1}]
+        self.assertTrue(config_module.save_config(self.config))
+
+    async def test_retained_jobs_block_destructive_changes_after_restart(self):
+        original = self.read_config_file()
+        for status in ("UNKNOWN", "CANCEL_REQUESTED", "IN_QUEUE", "IN_PROGRESS", "DOWNLOADING", "SUBMITTING"):
+            for restart in (False, True):
+                with self.subTest(status=status, restart=restart):
+                    self.manager.ledger.update("retained", worker_id="pool-1", endpoint_id="ep-123", status=status, job_id=None if status in {"UNKNOWN", "SUBMITTING"} else "owned-id")
+                    if restart:
+                        self.manager = self.runtime.ServerlessManager(types.SimpleNamespace(), self.secrets, self.ledger_path, self.session_factory)
+                        runtime_module.manager = self.manager
+                    else:
+                        self.manager.tasks["retained"] = types.SimpleNamespace(done=lambda: True)
+                    for fields in ({"api_key": "new-key"}, {"clear_api_key": True}, {"endpoint_id": "ep-other"}, {"type": "local", "port": 8188}):
+                        response = await config_routes.update_worker_endpoint(_FakeRequest(dict(fields, worker_id="pool-1")))
+                        self.assertEqual(response.status, 409, fields)
+                    response = await config_routes.delete_worker_endpoint(_FakeRequest({"worker_id": "pool-1"}))
+                    self.assertEqual(response.status, 409)
+                    worker = original["workers"][0]
+                    for workers in ([], [dict(worker, type="local")], [dict(worker, endpoint_id="ep-other")]):
+                        response = await config_routes.update_config_endpoint(_FakeRequest({"workers": workers}))
+                        self.assertEqual(response.status, 409, workers)
+                    self.assertEqual(self.read_config_file(), original)
+                    self.assertEqual(self.secrets.get("pool-1"), "saved-key")
+        self.session_factory.assert_not_awaited()
+
+    async def test_retained_jobs_allow_images_per_run_and_legacy_concurrency_saves(self):
+        # Upgrading from a config with concurrency=1 must not trip the busy guard,
+        # and the image count stays editable while old jobs are unresolved.
+        self.manager.ledger.update("retained", worker_id="pool-1", endpoint_id="ep-123", status="UNKNOWN")
+        response = await config_routes.update_worker_endpoint(_FakeRequest({
+            "worker_id": "pool-1", "endpoint_id": "ep-123", "jobs_per_run": 2, "concurrency": 2,
+        }))
+        self.assertEqual(response.status, 200)
+        saved = self.read_config_file()["workers"][0]
+        self.assertEqual(saved["jobs_per_run"], 2)
+        self.assertNotIn("concurrency", saved)
+        response = await config_routes.update_config_endpoint(_FakeRequest({"workers": [dict(saved, jobs_per_run=3, concurrency=5)]}))
+        self.assertEqual(response.status, 200)
+        self.assertEqual(self.read_config_file()["workers"][0]["jobs_per_run"], 3)
+
+    async def test_retained_job_allows_disable_and_rename_but_not_key_clear(self):
+        self.manager.ledger.update("retained", worker_id="pool-1", status="UNKNOWN")
+        response = await config_routes.update_worker_endpoint(_FakeRequest({"worker_id": "pool-1", "enabled": False, "name": "Paused"}))
+        self.assertEqual(response.status, 200)
+        self.assertEqual(self.read_config_file()["workers"][0]["name"], "Paused")
+        response = await config_routes.update_worker_endpoint(_FakeRequest({"worker_id": "pool-1", "clear_api_key": True}))
+        self.assertEqual(response.status, 409)
+        self.assertEqual(self.secrets.get("pool-1"), "saved-key")
+
+    async def test_terminal_or_other_pool_records_do_not_block_deletion(self):
+        self.manager.ledger.update("done", worker_id="pool-1", status="RESOLVED")
+        self.manager.ledger.update("other", worker_id="other", status="UNKNOWN")
+        response = await config_routes.delete_worker_endpoint(_FakeRequest({"worker_id": "pool-1"}))
+        self.assertEqual(response.status, 200)
+        self.assertIsNone(self.secrets.get("pool-1"))
+
+
+if __name__ == "__main__":
+    unittest.main()

tests/test_serverless_runtime.py

@@ -0,0 +1,170 @@
+import asyncio
+import importlib.util
+import sys
+import tempfile
+import types
+import unittest
+from pathlib import Path
+from unittest.mock import AsyncMock, patch
+
+ROOT = Path(__file__).resolve().parents[1]
+PACKAGE = "dist_serverless_runtime_tests"
+for name, path in [(PACKAGE, ROOT), (PACKAGE + ".api", ROOT / "api"), (PACKAGE + ".api.orchestration", ROOT / "api/orchestration")]:
+    module = types.ModuleType(name)
+    module.__path__ = [str(path)]
+    sys.modules[name] = module
+
+def load(name):
+    spec = importlib.util.spec_from_file_location(PACKAGE + ".api.orchestration." + name, ROOT / "api/orchestration" / (name + ".py"))
+    assert spec and spec.loader
+    module = importlib.util.module_from_spec(spec)
+    sys.modules[spec.name] = module
+    spec.loader.exec_module(module)
+    return module
+
+runtime = load("serverless_runtime")
+
+class Secrets:
+    def get(self, worker_id):
+        return "private-test-key"
+
+class RuntimeTests(unittest.IsolatedAsyncioTestCase):
+    async def asyncSetUp(self):
+        self.temp = tempfile.TemporaryDirectory()
+        self.server = types.SimpleNamespace(distributed_pending_jobs={"collector-job": asyncio.Queue()}, distributed_jobs_lock=asyncio.Lock())
+        self.manager = runtime.ServerlessManager(self.server, Secrets(), Path(self.temp.name) / "jobs.json", AsyncMock(return_value=object()))
+        self.manager.poll_seconds = 0
+        self.worker = {"id": "pool:1", "pool_id": "pool", "endpoint_id": "ep1", "timeout_seconds": 30, "type": "serverless"}
+        self.prepared = {"worker": self.worker, "workflow": {"1": {}}, "images": [], "manifest": [{"job_id": "collector-job", "prefix": "dist_x", "kind": "image"}]}
+
+    async def asyncTearDown(self):
+        await self.manager.cancel()
+        self.temp.cleanup()
+
+    async def test_job_id_persisted_before_status_and_results_injected(self):
+        api = types.SimpleNamespace(submit=AsyncMock(return_value="provider-job"), cancel=AsyncMock())
+        async def status(job_id):
+            self.assertEqual(self.manager.ledger.all()[0]["job_id"], "provider-job")
+            return {"status": "COMPLETED", "output": {"images": []}}
+        api.status = status
+        with patch.object(runtime, "RunpodClient", return_value=api), patch.object(runtime, "decode_results", AsyncMock(return_value={"collector-job": ["tensor"]})):
+            await self.manager.start("execution", "prompt", [self.prepared])
+            await self.manager.wait_for_execution("execution")
+        self.assertEqual(api.submit.await_count, 1)
+        item = self.server.distributed_pending_jobs["collector-job"].get_nowait()
+        self.assertEqual(item["worker_id"], "pool:1")
+        self.assertEqual(item["tensor"], "tensor")
+        self.assertTrue(item["is_last"])
+        self.assertEqual(self.manager.ledger.all()[0]["status"], "COMPLETED")
+
+    async def test_output_error_marks_failed_and_delivers_explicit_error(self):
+        api = types.SimpleNamespace(submit=AsyncMock(return_value="provider-job"), status=AsyncMock(return_value={"status": "COMPLETED", "output": {"error": "private-test-key"}}), cancel=AsyncMock())
+        with patch.object(runtime, "RunpodClient", return_value=api):
+            await self.manager.start("execution", "prompt", [self.prepared])
+            await self.manager.wait_for_execution("execution")
+        record = self.manager.ledger.all()[0]
+        self.assertEqual(record["status"], "FAILED")
+        item = self.server.distributed_pending_jobs["collector-job"].get_nowait()
+        self.assertIn("serverless_error", item)
+        self.assertNotIn("private-test-key", str(record) + str(item))
+
+    async def test_ambiguous_submit_never_retries(self):
+        api = types.SimpleNamespace(submit=AsyncMock(side_effect=runtime.AmbiguousSubmission("Unknown submission")), cancel=AsyncMock())
+        with patch.object(runtime, "RunpodClient", return_value=api):
+            await self.manager.start("execution", "prompt", [self.prepared])
+            await self.manager.wait_for_execution("execution")
+        self.assertEqual(api.submit.await_count, 1)
+        self.assertEqual(self.manager.ledger.all()[0]["status"], "UNKNOWN")
+
+    async def test_cancel_targets_owned_job_only(self):
+        polled = asyncio.Event()
+        async def status(_job):
+            polled.set()
+            await asyncio.Event().wait()
+        api = types.SimpleNamespace(submit=AsyncMock(return_value="owned-job"), status=status, cancel=AsyncMock(return_value={"status": "CANCELLED"}))
+        with patch.object(runtime, "RunpodClient", return_value=api):
+            await self.manager.start("execution", "prompt", [self.prepared])
+            await polled.wait()
+            await self.manager.cancel(worker_id="other-pool")
+            api.cancel.assert_not_awaited()
+            await self.manager.cancel(worker_id="pool")
+        api.cancel.assert_awaited_once_with("owned-job")
+
+    async def test_all_images_of_a_run_submit_at_once_ignoring_legacy_concurrency(self):
+        self.assertEqual(runtime.PER_WORKER_JOB_LIMIT, 16)
+        gate = asyncio.Event()
+        submitted = []
+        async def submit(*args):
+            submitted.append(args)
+            return f"provider-{len(submitted)}"
+        async def status(_job):
+            await gate.wait()
+            return {"status": "COMPLETED", "output": {"images": []}}
+        api = types.SimpleNamespace(submit=submit, status=status, cancel=AsyncMock())
+        # A config saved before the setting was removed still carries concurrency=1.
+        legacy = dict(self.worker, concurrency=1)
+        jobs = [dict(self.prepared, worker=dict(legacy, id=f"pool:{i}")) for i in range(1, 4)]
+        with patch.object(runtime, "RunpodClient", return_value=api), patch.object(runtime, "decode_results", AsyncMock(return_value={"collector-job": ["tensor"]})):
+            await self.manager.start("execution", "prompt", jobs)
+            for _ in range(50):
+                if len(submitted) == 3:
+                    break
+                await asyncio.sleep(0)
+            self.assertEqual(len(submitted), 3)
+            gate.set()
+            await self.manager.wait_for_execution("execution")
+
+    async def test_per_pool_job_limit_bounds_submission(self):
+        patcher = patch.object(runtime, "PER_WORKER_JOB_LIMIT", 1)
+        patcher.start()
+        self.addCleanup(patcher.stop)
+        gate = asyncio.Event()
+        reached = asyncio.Event()
+        count = 0
+        async def submit(*args):
+            nonlocal count
+            count += 1
+            reached.set()
+            return f"provider-{count}"
+        async def status(_job):
+            await gate.wait()
+            return {"status": "COMPLETED", "output": {"images": []}}
+        api = types.SimpleNamespace(submit=submit, status=status, cancel=AsyncMock())
+        second = dict(self.prepared, worker=dict(self.worker, id="pool:2"))
+        with patch.object(runtime, "RunpodClient", return_value=api), patch.object(runtime, "decode_results", AsyncMock(return_value={"collector-job": ["tensor"]})):
+            await self.manager.start("execution", "prompt", [self.prepared, second])
+            await reached.wait()
+            await asyncio.sleep(0)
+            self.assertEqual(count, 1)
+            gate.set()
+            await self.manager.wait_for_execution("execution")
+        self.assertEqual(count, 2)
+
+    async def test_cancel_persisted_job_after_master_restart(self):
+        self.manager.ledger.update("old", worker_id="pool", endpoint_id="old-endpoint", job_id="old-job", status="IN_PROGRESS", created_at=1, updated_at=1)
+        api = types.SimpleNamespace(cancel=AsyncMock(return_value={"status": "CANCELLED"}))
+        with patch.object(runtime, "RunpodClient", return_value=api) as client:
+            await self.manager.cancel(worker_id="pool")
+        api.cancel.assert_awaited_once_with("old-job")
+        self.assertEqual(client.call_args.args[1], "old-endpoint")
+        self.assertEqual(self.manager.ledger.all()[0]["status"], "CANCELLED")
+
+    async def test_master_failure_cancels_job_without_partial_success(self):
+        self.server.prompt_queue = types.SimpleNamespace(get_history=lambda _id: {"prompt": {"status": {"status_str": "error"}}})
+        api = types.SimpleNamespace(submit=AsyncMock(return_value="job"), cancel=AsyncMock(return_value={"status": "CANCELLED"}))
+        with patch.object(runtime, "RunpodClient", return_value=api):
+            await self.manager.start("execution", "prompt", [self.prepared])
+            await self.manager.wait_for_execution("execution")
+        api.submit.assert_not_awaited()
+        self.assertEqual(self.manager.ledger.all()[0]["status"], "FAILED")
+
+    async def test_deadline_includes_local_slot_wait(self):
+        self.prepared["worker"] = dict(self.worker, timeout_seconds=0.01)
+        api = types.SimpleNamespace(submit=AsyncMock(return_value="job"), status=AsyncMock(side_effect=lambda _: asyncio.sleep(5)), cancel=AsyncMock(return_value={"status": "CANCELLED"}))
+        # A blocked slot expires without a billable submission.
+        self.manager.pool_limits["pool"] = asyncio.Semaphore(0)
+        with patch.object(runtime, "RunpodClient", return_value=api):
+            await self.manager.start("execution", "prompt", [self.prepared])
+            await self.manager.wait_for_execution("execution")
+        api.submit.assert_not_awaited()
+        self.assertEqual(self.manager.ledger.all()[0]["status"], "TIMED_OUT")

tests/test_serverless_status.py

@@ -0,0 +1,98 @@
+import importlib.util
+import json
+import sys
+import types
+import unittest
+from pathlib import Path
+from unittest.mock import AsyncMock, patch
+
+ROOT = Path(__file__).resolve().parents[1]
+PKG = "dist_serverless_status_tests"
+
+
+class StatusTests(unittest.IsolatedAsyncioTestCase):
+    async def asyncSetUp(self):
+        def mod(name, **kwargs):
+            result = types.ModuleType(name)
+            result.__dict__.update(kwargs)
+            return result
+        self.manager = types.SimpleNamespace(health=AsyncMock(return_value={"ok": True, "queueRemaining": 0, "message": "Ready (scales from zero)"}), public_jobs=lambda _: [], cancel=AsyncMock(return_value=1))
+        self.pool = {"id": "pool", "type": "serverless", "endpoint_id": "ep"}
+        modules = {PKG: mod(PKG, __path__=[str(ROOT)]), PKG + ".api": mod("api", __path__=[str(ROOT/'api')]),
+                   PKG + ".utils": mod("utils", __path__=[]),
+                   PKG + ".utils.config": mod("config", load_config=lambda: {"workers": [self.pool]}),
+                   PKG + ".api.orchestration": mod("orchestration", __path__=[str(ROOT/'api/orchestration')]),
+                   PKG + ".api.orchestration.serverless_runtime": mod("runtime", get_manager=lambda: self.manager),
+                   "server": mod("server", PromptServer=types.SimpleNamespace(instance=types.SimpleNamespace(routes=types.SimpleNamespace(get=lambda _: lambda f: f, post=lambda _: lambda f: f))))}
+        with patch.dict(sys.modules, modules):
+            spec = importlib.util.spec_from_file_location(PKG+'.api.serverless_routes', ROOT/'api/serverless_routes.py')
+            self.routes = importlib.util.module_from_spec(spec)
+            spec.loader.exec_module(self.routes)
+
+    async def test_health_only_never_submits_and_supports_scale_to_zero(self):
+        request = types.SimpleNamespace(json=AsyncMock(return_value={"worker_id": "pool"}))
+        result = await self.routes.test_serverless_endpoint(request)
+        self.assertEqual(result.status, 200)
+        self.assertTrue(json.loads(result.text)["ok"])
+        self.manager.health.assert_awaited_once_with(self.pool, fresh=True)
+        self.manager.cancel.assert_not_awaited()
+
+    async def test_unknown_pool_cannot_cancel_other_jobs(self):
+        request = types.SimpleNamespace(json=AsyncMock(return_value={"worker_id": "other"}))
+        result = await self.routes.cancel_serverless_endpoint(request)
+        self.assertEqual(result.status, 404)
+        self.manager.cancel.assert_not_awaited()
+
+    async def test_transport_error_does_not_leak_credentials(self):
+        self.manager.health.side_effect = RuntimeError("Bearer secret-token https://signed.invalid/?token=value")
+        request = types.SimpleNamespace(match_info={"worker_id": "pool"})
+        result = await self.routes.serverless_status_endpoint(request)
+        self.assertFalse(json.loads(result.text)["ok"])
+        self.assertNotIn("secret-token", result.text)
+        self.assertNotIn("signed.invalid", result.text)
+
+    async def test_cancel_uses_only_requested_pool(self):
+        request = types.SimpleNamespace(json=AsyncMock(return_value={"worker_id": "pool"}))
+        result = await self.routes.cancel_serverless_endpoint(request)
+        self.assertEqual(result.status, 200)
+        self.manager.cancel.assert_awaited_once_with(worker_id="pool")
+
+    async def test_reconcile_only_reads_the_requested_pools_jobs(self):
+        self.manager.reconcile = AsyncMock(return_value=2)
+        request = types.SimpleNamespace(json=AsyncMock(return_value={"worker_id": "pool"}))
+        result = await self.routes.reconcile_serverless_endpoint(request)
+        self.assertEqual(result.status, 200)
+        self.assertEqual(json.loads(result.text)["resolved"], 2)
+        self.manager.reconcile.assert_awaited_once_with(worker_id="pool")
+        self.manager.cancel.assert_not_awaited()
+
+    async def test_resolve_requires_explicit_boolean_confirmation_and_record_id(self):
+        self.manager.acknowledge_recovery = AsyncMock()
+        for payload in ({"worker_id": "pool", "record_id": "record"},
+                        {"worker_id": "pool", "record_id": "record", "provider_checked": "true"},
+                        {"worker_id": "pool", "provider_checked": True}):
+            with self.subTest(payload=payload):
+                result = await self.routes.resolve_serverless_endpoint(types.SimpleNamespace(json=AsyncMock(return_value=payload)))
+                self.assertEqual(result.status, 400)
+        self.manager.acknowledge_recovery.assert_not_awaited()
+
+    async def test_resolve_is_scoped_and_does_not_claim_provider_cancellation(self):
+        self.manager.acknowledge_recovery = AsyncMock()
+        request = types.SimpleNamespace(json=AsyncMock(return_value={"worker_id": "pool", "record_id": "record", "provider_checked": True}))
+        result = await self.routes.resolve_serverless_endpoint(request)
+        self.assertEqual(result.status, 200)
+        self.manager.acknowledge_recovery.assert_awaited_once_with("pool", "record", provider_checked=True)
+        self.assertIn("not provider-confirmed", json.loads(result.text)["message"])
+        self.manager.cancel.assert_not_awaited()
+
+    async def test_live_or_mismatched_record_refuses_manual_resolution(self):
+        self.manager.acknowledge_recovery = AsyncMock(side_effect=ValueError("Unresolved inactive job not found for this pool"))
+        request = types.SimpleNamespace(json=AsyncMock(return_value={"worker_id": "pool", "record_id": "record", "provider_checked": True}))
+        result = await self.routes.resolve_serverless_endpoint(request)
+        self.assertEqual(result.status, 409)
+
+    async def test_failed_health_still_exposes_recovery_ids(self):
+        self.manager.health.side_effect = RuntimeError("private transport error")
+        self.manager.public_jobs = lambda _: [{"record_id": "record", "status": "UNKNOWN"}]
+        result = await self.routes.serverless_status_endpoint(types.SimpleNamespace(match_info={"worker_id": "pool"}))
+        self.assertEqual(json.loads(result.text)["jobs"][0]["record_id"], "record")

tests/test_transfer_codec.py

@@ -0,0 +1,219 @@
+import importlib.util
+import io
+import sys
+from pathlib import Path
+
+import numpy as np
+import pytest
+import torch
+from PIL import Image
+
+
+def _load_codec():
+    path = Path(__file__).resolve().parents[1] / "utils" / "transfer_codec.py"
+    spec = importlib.util.spec_from_file_location("dist_transfer_codec_test", path)
+    module = importlib.util.module_from_spec(spec)
+    sys.modules["dist_transfer_codec_test"] = module
+    spec.loader.exec_module(module)
+    return module
+
+
+tc = _load_codec()
+
+
+def _smooth_frames(count=4, height=67, width=91):
+    """Smooth moving gradient, closer to generated content than random noise."""
+    yy, xx = np.mgrid[0:height, 0:width].astype(np.float32)
+    frames = []
+    for i in range(count):
+        r = 0.5 + 0.5 * np.sin((xx + 3 * i) / 13.0)
+        g = 0.5 + 0.5 * np.cos((yy - 2 * i) / 11.0)
+        b = (xx + yy + 5 * i) / (width + height + 5 * count)
+        frames.append(np.stack([r, g, b], axis=-1))
+    return torch.from_numpy(np.stack(frames)).float()
+
+
+def _legacy_master_tensor(frame_tensor):
+    """What the unmodified pipeline delivered: tensor_to_pil -> PNG -> pil_to_tensor."""
+    img = Image.fromarray((255 * frame_tensor.numpy()).astype(np.uint8))
+    buf = io.BytesIO()
+    img.save(buf, format="PNG", compress_level=0)
+    with Image.open(io.BytesIO(buf.getvalue())) as decoded:
+        return np.array(decoded.convert("RGB")).astype(np.float32) / 255.0
+
+
+def _round_trip(frames_u8, fmt, quality=90, max_chunk_bytes=10**9):
+    out = []
+    chunks = list(tc.encode_chunks(frames_u8, fmt, quality, max_chunk_bytes))
+    for chunk in chunks:
+        envelope = {k: v for k, v in chunk.items() if k != "parts"}
+        out.extend(tc.decode_chunk(envelope, chunk["parts"]))
+    return chunks, out
+
+
+def _psnr(a, b):
+    mse = np.mean((a.astype(np.float64) - b.astype(np.float64)) ** 2)
+    return float("inf") if mse == 0 else 10 * np.log10(255.0**2 / mse)
+
+
+@pytest.mark.parametrize("fmt", ["png", "ffv1"])
+def test_lossless_formats_reproduce_legacy_master_tensors_exactly(fmt):
+    images = _smooth_frames()
+    frames = tc.tensor_batch_to_uint8(images)
+    _, decoded = _round_trip(frames, fmt)
+
+    assert len(decoded) == images.shape[0]
+    for i, frame in enumerate(decoded):
+        got = tc.uint8_frame_to_tensor_array(frame)[0]
+        assert np.array_equal(got, _legacy_master_tensor(images[i]))
+
+
+@pytest.mark.parametrize("fmt", ["jpeg", "webp", "h264", "h265", "av1"])
+def test_lossy_formats_round_trip_odd_sizes_with_reasonable_quality(fmt):
+    if fmt in tc.VIDEO_FORMATS and not tc.video_codec_available(fmt):
+        pytest.skip(f"{fmt} encoder not available in this PyAV build")
+    frames = tc.tensor_batch_to_uint8(_smooth_frames())
+    _, decoded = _round_trip(frames, fmt, quality=90)
+
+    assert len(decoded) == frames.shape[0]
+    for i, frame in enumerate(decoded):
+        assert frame.shape == frames[i].shape
+        assert frame.dtype == np.uint8
+        assert _psnr(frame, frames[i]) > 30
+
+
+def test_h265_handles_frames_smaller_than_ctu():
+    if not tc.video_codec_available("h265"):
+        pytest.skip("h265 encoder not available")
+    frames = tc.tensor_batch_to_uint8(_smooth_frames(count=3, height=17, width=23))
+    _, decoded = _round_trip(frames, "h265")
+    assert [f.shape for f in decoded] == [(17, 23, 3)] * 3
+
+
+def test_image_formats_split_chunks_by_byte_cap_and_keep_order():
+    frames = tc.tensor_batch_to_uint8(_smooth_frames(count=5))
+    one = len(tc.encode_image_frame(frames[0], "png", 90))
+    chunks, decoded = _round_trip(frames, "png", max_chunk_bytes=one * 2 + 1)
+
+    assert len(chunks) >= 3
+    assert [c["start_index"] for c in chunks] == sorted(c["start_index"] for c in chunks)
+    assert sum(c["count"] for c in chunks) == 5
+    assert all(len(c["parts"]) == c["count"] for c in chunks)
+    assert np.array_equal(np.stack(decoded), frames)
+
+
+def test_video_formats_split_chunks_by_frame_cap(monkeypatch):
+    monkeypatch.setattr(tc, "MAX_VIDEO_CHUNK_FRAMES", 2)
+    frames = tc.tensor_batch_to_uint8(_smooth_frames(count=5))
+    chunks, decoded = _round_trip(frames, "ffv1")
+
+    assert [(c["start_index"], c["count"]) for c in chunks] == [(0, 2), (2, 2), (4, 1)]
+    assert all(len(c["parts"]) == 1 for c in chunks)
+    assert np.array_equal(np.stack(decoded), frames)
+
+
+def test_tensor_batch_to_uint8_clips_and_normalizes_channels():
+    rgba = torch.tensor([[[[1.5, -0.2, 0.5, 0.3]]]])
+    assert tc.tensor_batch_to_uint8(rgba).tolist() == [[[[255, 0, 127]]]]
+
+    gray = torch.full((1, 2, 2, 1), 0.5)
+    out = tc.tensor_batch_to_uint8(gray)
+    assert out.shape == (1, 2, 2, 3)
+    assert (out == 127).all()
+
+
+def test_quality_to_crf_mapping():
+    assert tc.quality_to_crf(100, 51) == 0
+    assert tc.quality_to_crf(90, 51) == 13
+    assert tc.quality_to_crf(80, 51) == 19
+    assert tc.quality_to_crf(90, 63) == 16
+    assert tc.quality_to_crf(1, 51) == 51
+    assert tc.quality_to_crf("bogus", 51) == tc.quality_to_crf(tc.DEFAULT_TRANSFER_QUALITY, 51)
+
+
+def test_normalize_format_rejects_unknown_values():
+    assert tc.normalize_format(" H264 ") == "h264"
+    assert tc.normalize_format(None) == tc.DEFAULT_TRANSFER_FORMAT
+    with pytest.raises(tc.TransferCodecError):
+        tc.normalize_format("gif")
+
+
+def test_decode_chunk_validates_envelope_against_payload():
+    frames = tc.tensor_batch_to_uint8(_smooth_frames(count=2))
+    chunk = next(tc.encode_chunks(frames, "png", 90, 10**9))
+    envelope = {k: v for k, v in chunk.items() if k != "parts"}
+
+    with pytest.raises(tc.TransferCodecError, match="image parts"):
+        tc.decode_chunk({**envelope, "count": 3}, chunk["parts"])
+    with pytest.raises(tc.TransferCodecError, match="expected"):
+        tc.decode_chunk({**envelope, "width": 10}, chunk["parts"])
+    with pytest.raises(tc.TransferCodecError, match="count"):
+        tc.decode_chunk({**envelope, "count": 0}, chunk["parts"])
+    with pytest.raises(tc.TransferCodecError):
+        tc.decode_chunk(envelope, [b"not an image", b"nope"])
+
+    video = next(tc.encode_chunks(frames, "ffv1", 90, 10**9))
+    video_env = {k: v for k, v in video.items() if k != "parts"}
+    with pytest.raises(tc.TransferCodecError, match="frames"):
+        tc.decode_chunk({**video_env, "count": 5}, video["parts"])
+
+
+def test_legacy_format_is_not_chunk_encoded():
+    frames = tc.tensor_batch_to_uint8(_smooth_frames(count=1))
+    with pytest.raises(tc.TransferCodecError):
+        list(tc.encode_chunks(frames, "legacy_png", 90, 10**9))
+
+
+# --------------------------------------------------------------------------- #
+# Size bounds on finalized payloads
+# --------------------------------------------------------------------------- #
+
+def _noise_frames(count=30, height=360, width=640, seed=97):
+    """High-entropy frames: worst case for every codec, and enough encoder
+    lookahead that pre-flush buffer sizes badly underestimate final sizes."""
+    return np.random.default_rng(seed).integers(0, 256, size=(count, height, width, 3), dtype=np.uint8)
+
+
+@pytest.mark.parametrize("fmt", ["h264", "ffv1"])
+def test_video_chunks_are_bounded_after_encoder_flush(fmt):
+    frames = _noise_frames()
+    limit = 1024 * 1024
+    # Sanity: one unconstrained encode of this batch is far above the limit,
+    # so the bound below is actually being enforced.
+    unbounded = next(tc.encode_chunks(frames, fmt, 90, 10**12))
+    assert len(unbounded["parts"][0]) > 3 * limit
+
+    chunks = list(tc.encode_chunks(frames, fmt, 90, limit))
+
+    assert all(len(c["parts"]) == 1 and len(c["parts"][0]) <= limit for c in chunks)
+    assert [c["start_index"] for c in chunks] == list(np.cumsum([0] + [c["count"] for c in chunks[:-1]]))
+    assert sum(c["count"] for c in chunks) == len(frames)
+    decoded = [f for c in chunks for f in tc.decode_chunk(c, c["parts"])]
+    assert len(decoded) == len(frames)
+    if fmt == "ffv1":
+        assert np.array_equal(np.stack(decoded), frames)
+
+
+def test_single_video_frame_may_exceed_chunk_target_up_to_frame_limit():
+    frames = _noise_frames(count=3)
+    one_frame = len(next(tc.encode_chunks(frames[:1], "ffv1", 90, 10**12))["parts"][0])
+
+    chunks = list(tc.encode_chunks(frames, "ffv1", 90, one_frame // 2, one_frame * 2))
+
+    assert [c["count"] for c in chunks] == [1, 1, 1]
+    assert all(one_frame // 2 < len(c["parts"][0]) <= one_frame * 2 for c in chunks)
+
+
+@pytest.mark.parametrize("fmt", ["ffv1", "h264", "png"])
+def test_frame_that_cannot_fit_alone_raises(fmt):
+    frames = _noise_frames(count=2)
+    with pytest.raises(tc.FrameTooLargeError, match="request limit"):
+        list(tc.encode_chunks(frames, fmt, 90, 64 * 1024, 64 * 1024))
+
+
+def test_still_chunks_are_bounded():
+    frames = _noise_frames(count=10)
+    limit = 1024 * 1024
+    chunks = list(tc.encode_chunks(frames, "jpeg", 90, limit))
+    assert all(sum(len(p) for p in c["parts"]) <= limit for c in chunks)
+    assert sum(c["count"] for c in chunks) == 10

tests/test_v3_collector_transfer.py

@@ -0,0 +1,125 @@
+"""Registered V3 DistributedCollector: transfer options in the public schema and forwarded to the runtime.
+
+Runs without a ComfyUI checkout by loading nodes/v3.py against a recording
+stand-in for comfy_api's io module. tests/test_v3_migration.py covers the same
+boundary against the real framework when COMFYUI_SOURCE_ROOT is set.
+"""
+import importlib.util
+import sys
+import types
+from pathlib import Path
+
+import pytest
+
+ROOT = Path(__file__).resolve().parents[1]
+PKG = "dist_v3_transfer_testpkg"
+
+
+class _Field:
+    def __init__(self, kind, id=None, **kwargs):
+        self.kind = kind
+        self.id = id
+        self.kwargs = kwargs
+
+
+def _io_type(kind):
+    return types.SimpleNamespace(
+        Input=lambda id, **kw: _Field(kind, id, **kw),
+        Output=lambda id=None, **kw: _Field(kind, id, **kw),
+    )
+
+
+def _fake_io():
+    io = types.ModuleType("io")
+
+    class ComfyNode:
+        pass
+
+    io.ComfyNode = ComfyNode
+    io.Schema = lambda **kw: types.SimpleNamespace(**kw)
+    io.NodeOutput = lambda *values, **kw: ("NodeOutput", values, kw)
+    io.NumberDisplay = types.SimpleNamespace(number="number")
+    io.Hidden = types.SimpleNamespace(unique_id="unique_id", extra_pnginfo="extra_pnginfo")
+    for name in ("Int", "Float", "String", "Boolean", "Combo", "Image", "Audio",
+                 "AnyType", "Model", "Conditioning", "Vae"):
+        setattr(io, name, _io_type(name))
+    return io
+
+
+@pytest.fixture
+def v3(monkeypatch):
+    calls = []
+
+    class CollectorRuntime:
+        def run(self, **kwargs):
+            calls.append(kwargs)
+            return (kwargs["images"], kwargs["audio"])
+
+    def module(name, **attrs):
+        mod = types.ModuleType(name)
+        mod.__dict__.update(attrs)
+        monkeypatch.setitem(sys.modules, name, mod)
+        return mod
+
+    for name in [n for n in sys.modules if n == PKG or n.startswith(PKG + ".")]:
+        monkeypatch.delitem(sys.modules, name)
+    module(PKG, __path__=[])
+    module(f"{PKG}.nodes", __path__=[])
+    module(f"{PKG}.utils", __path__=[])
+    module(f"{PKG}.nodes.utilities")
+    module(f"{PKG}.nodes.distributed_upscale", UltimateSDUpscaleDistributed=object)
+    module(f"{PKG}.nodes.collector", DistributedCollectorNode=CollectorRuntime)
+    module("comfy", __path__=[])
+    module("comfy.samplers", KSampler=types.SimpleNamespace(SAMPLERS=["euler"], SCHEDULERS=["normal"]))
+    module("comfy_api", __path__=[])
+    module("comfy_api.v0_0_2", io=_fake_io())
+
+    codec_spec = importlib.util.spec_from_file_location(f"{PKG}.utils.transfer_codec", ROOT / "utils" / "transfer_codec.py")
+    codec = importlib.util.module_from_spec(codec_spec)
+    monkeypatch.setitem(sys.modules, f"{PKG}.utils.transfer_codec", codec)
+    codec_spec.loader.exec_module(codec)
+
+    spec = importlib.util.spec_from_file_location(f"{PKG}.nodes.v3", ROOT / "nodes" / "v3.py")
+    mod = importlib.util.module_from_spec(spec)
+    monkeypatch.setitem(sys.modules, f"{PKG}.nodes.v3", mod)
+    spec.loader.exec_module(mod)
+    return mod, codec, calls
+
+
+def test_registered_collector_schema_exposes_optional_transfer_inputs(v3):
+    mod, codec, _ = v3
+    schema = mod.DistributedCollector.define_schema()
+    inputs = {field.id: field for field in schema.inputs}
+
+    assert [field.id for field in schema.inputs] == [
+        "load_balance", "images", "audio", "transfer_format", "transfer_quality"]
+    fmt = inputs["transfer_format"]
+    assert fmt.kind == "Combo"
+    assert fmt.kwargs["options"] == list(codec.TRANSFER_FORMATS)
+    assert fmt.kwargs["default"] == "legacy_png"
+    assert fmt.kwargs["optional"] is True
+    quality = inputs["transfer_quality"]
+    assert quality.kind == "Int"
+    assert (quality.kwargs["default"], quality.kwargs["min"], quality.kwargs["max"]) == (90, 1, 100)
+    assert quality.kwargs["optional"] is True
+    assert schema.is_input_list is True
+
+
+def test_registered_collector_forwards_transfer_options(v3):
+    mod, _, calls = v3
+
+    mod.DistributedCollector.execute(images=["img"], audio=[None], transfer_format=["av1"], transfer_quality=[70],
+                                     multi_job_id=["job"], is_worker=[True])
+
+    assert calls[-1]["transfer_format"] == ["av1"]
+    assert calls[-1]["transfer_quality"] == [70]
+    assert calls[-1]["multi_job_id"] == ["job"]
+
+
+def test_registered_collector_defaults_to_legacy_transfer(v3):
+    mod, _, calls = v3
+
+    mod.DistributedCollector.execute(images=["img"])
+
+    assert calls[-1]["transfer_format"] == "legacy_png"
+    assert calls[-1]["transfer_quality"] == 90

tests/test_v3_migration.py

@@ -0,0 +1,21 @@
+"""Real-framework acceptance; opt in with COMFYUI_SOURCE_ROOT."""
+import os
+from pathlib import Path
+import subprocess
+import sys
+
+import pytest
+
+
+def test_native_v3_runtime():
+    comfy_root = os.environ.get('COMFYUI_SOURCE_ROOT')
+    if not comfy_root:
+        pytest.skip('Set COMFYUI_SOURCE_ROOT to run native ComfyUI V3 acceptance')
+    helper = Path(__file__).parent / 'helpers' / 'v3_runtime_check.py'
+    result = subprocess.run(
+        [sys.executable, str(helper), str(Path(comfy_root).resolve())],
+        capture_output=True, text=True, timeout=120,
+        env={**os.environ, 'COMFYUI_IS_WORKER': '1'},
+    )
+    assert result.returncode == 0, result.stdout + '\n' + result.stderr
+    assert 'V3_ACCEPTANCE_OK' in result.stdout

tests/test_worker_ports.py

@@ -0,0 +1,113 @@
+import importlib.util
+import os
+import socket
+import unittest
+from pathlib import Path
+from unittest.mock import patch
+
+
+def load_ports():
+    path = Path(__file__).resolve().parents[1] / "workers" / "ports.py"
+    spec = importlib.util.spec_from_file_location("worker_ports_test", path)
+    module = importlib.util.module_from_spec(spec)
+    spec.loader.exec_module(module)
+    return module
+
+
+class WorkerPortTests(unittest.TestCase):
+    def setUp(self):
+        self.ports = load_ports()
+
+    def test_allocation_starts_above_actual_master_and_skips_assigned_and_occupied(self):
+        workers = [
+            {"id": "existing", "host": "localhost", "port": 8190, "enabled": False},
+            {"id": "remote", "host": "remote.example", "port": 8192},
+        ]
+        with patch.object(self.ports, "is_port_available", side_effect=lambda port: port != 8191):
+            self.assertEqual(self.ports.allocate_worker_ports(8189, workers, 3), [8192, 8193, 8194])
+
+    def test_local_host_forms_reserve_ports(self):
+        for host in ["::1", "[::1]", "http://localhost/", "HTTPS://LOCALHOST", "0.0.0.0", None]:
+            with self.subTest(host=host), patch.object(self.ports, "is_port_available", return_value=True):
+                self.assertEqual(self.ports.allocate_worker_ports(8189, [{"id": "local", "host": host, "port": 8190}], 1), [8191])
+
+    def test_exhaustion_is_explicit_not_a_partial_allocation(self):
+        with patch.object(self.ports, "is_port_available", return_value=True):
+            with self.assertRaisesRegex(ValueError, "available.*ports"):
+                self.ports.allocate_worker_ports(65534, [], 2)
+
+    def test_launch_rejects_master_port_without_reassigning_configuration(self):
+        worker = {"id": "manual", "port": 8189}
+        with self.assertRaisesRegex(ValueError, "master.*8189"):
+            self.ports.validate_worker_port(worker, 8189, [])
+        self.assertEqual(worker["port"], 8189)
+
+    def test_launch_rejects_another_local_workers_reserved_port(self):
+        worker = {"id": "manual", "port": 8190}
+        other = {"id": "other", "host": None, "port": 8190, "enabled": False}
+        with self.assertRaisesRegex(ValueError, "other"):
+            self.ports.validate_worker_port(worker, 8189, [worker, other])
+
+    def test_launch_ignores_itself_and_remote_workers_with_same_port(self):
+        worker = {"id": "manual", "port": 8190}
+        other = {"id": "remote", "host": "example.com", "port": 8190}
+        with patch.object(self.ports, "is_port_available", return_value=True):
+            self.ports.validate_worker_port(worker, 8189, [worker, other])
+
+    def test_launch_rejects_an_occupied_port(self):
+        with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as listener:
+            listener.bind(("127.0.0.1", 0))
+            listener.listen()
+            port = listener.getsockname()[1]
+            self.assertFalse(self.ports.is_port_available(port))
+            with self.assertRaisesRegex(ValueError, "already in use"):
+                self.ports.validate_worker_port({"id": "manual", "port": port}, 8189, [])
+
+    @unittest.skipIf(os.name == "nt", "asyncio does not reuse addresses on Windows")
+    def test_recently_closed_connection_does_not_block_worker_restart(self):
+        with socket.socket() as listener:
+            listener.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
+            listener.bind(("127.0.0.1", 0))
+            listener.listen(1)
+            port = listener.getsockname()[1]
+            with socket.create_connection(("127.0.0.1", port), timeout=2) as client:
+                accepted, _ = listener.accept()
+                with accepted:
+                    accepted.settimeout(2)
+                    accepted.shutdown(socket.SHUT_WR)
+                    self.assertEqual(client.recv(1), b"")
+                    client.shutdown(socket.SHUT_WR)
+                    self.assertEqual(accepted.recv(1), b"")
+        self.assertTrue(self.ports.is_port_available(port))
+        self.ports.validate_worker_port({"id": "restart", "port": port}, 1, [])
+        with socket.socket() as restarted:
+            restarted.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
+            restarted.bind(("127.0.0.1", port))
+            restarted.listen(1)
+
+    def test_active_listener_with_reuseaddr_is_still_a_conflict(self):
+        with socket.socket() as listener:
+            listener.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
+            listener.bind(("127.0.0.1", 0))
+            listener.listen(1)
+            self.assertFalse(self.ports.is_port_available(listener.getsockname()[1]))
+
+    @unittest.skipUnless(socket.has_ipv6, "IPv6 unavailable")
+    def test_ipv6_only_listener_is_still_a_conflict(self):
+        with socket.socket(socket.AF_INET6, socket.SOCK_STREAM) as listener:
+            listener.setsockopt(socket.IPPROTO_IPV6, socket.IPV6_V6ONLY, 1)
+            try:
+                listener.bind(("::1", 0))
+            except OSError as exc:
+                self.skipTest(f"IPv6 loopback unavailable: {exc}")
+            listener.listen(1)
+            self.assertFalse(self.ports.is_port_available(listener.getsockname()[1]))
+
+    def test_invalid_ports_fail_clearly(self):
+        for port in [0, 65536, "not-a-port", None, True, 8190.5]:
+            with self.subTest(port=port), self.assertRaisesRegex(ValueError, "port"):
+                self.ports.validate_worker_port({"id": "manual", "port": port}, 8189, [])
+
+
+if __name__ == "__main__":
+    unittest.main()

tests/test_worker_process_runtime.py

@@ -1,11 +1,16 @@
 import importlib.util
+import os
 import sys
+import tempfile
 import types
 import unittest
 from argparse import Namespace
 from pathlib import Path
 from unittest.mock import patch
 
+from sqlalchemy import create_engine
+from sqlalchemy.engine import URL, make_url
+
 
 def _load_process_module(module_filename: str):
     module_path = Path(__file__).resolve().parents[1] / "workers" / "process" / module_filename
@@ -21,7 +26,7 @@ def _load_process_module(module_filename: str):
     sys.modules[package_name] = root_pkg
 
     workers_pkg = types.ModuleType(f"{package_name}.workers")
-    workers_pkg.__path__ = []
+    workers_pkg.__path__ = [str(module_path.parents[1])]
     sys.modules[f"{package_name}.workers"] = workers_pkg
 
     process_pkg = types.ModuleType(f"{package_name}.workers.process")
@@ -39,8 +44,23 @@ def _load_process_module(module_filename: str):
 
     process_module = types.ModuleType(f"{package_name}.utils.process")
     process_module.get_python_executable = lambda: "/usr/bin/test-python"
+    process_module.is_process_alive = lambda _pid: False
+    process_module.terminate_process = lambda *_args, **_kwargs: None
     sys.modules[f"{package_name}.utils.process"] = process_module
 
+    config_module = types.ModuleType(f"{package_name}.utils.config")
+    config_module.load_config = lambda: {"workers": [], "settings": {"stop_workers_on_master_exit": False}}
+    config_module.save_config = lambda _config: None
+    sys.modules[f"{package_name}.utils.config"] = config_module
+    constants_module = types.ModuleType(f"{package_name}.utils.constants")
+    constants_module.PROCESS_TERMINATION_TIMEOUT = 1
+    constants_module.PROCESS_WAIT_TIMEOUT = 1
+    constants_module.WORKER_CHECK_INTERVAL = 0.01
+    sys.modules[f"{package_name}.utils.constants"] = constants_module
+    network_module = types.ModuleType(f"{package_name}.utils.network")
+    network_module.get_server_port = lambda: 8189
+    sys.modules[f"{package_name}.utils.network"] = network_module
+
     spec = importlib.util.spec_from_file_location(
         f"{package_name}.workers.process.{module_name}",
         module_path,
@@ -70,6 +90,145 @@ class ComfyRootDiscoveryTests(unittest.TestCase):
 
 
 class LaunchCommandBuilderTests(unittest.TestCase):
+    def build_command(self, root, worker=None, runtime=None):
+        builder = launch_builder_module.LaunchCommandBuilder()
+        worker = worker or {"id": "worker-a", "port": 8190}
+        runtime = runtime if runtime is not None else Namespace(database_url=None)
+        with patch.object(builder, "_get_runtime_args", return_value=runtime):
+            return builder.build_launch_command(worker, str(root))
+
+    def test_database_is_unique_and_stable_by_worker_id(self):
+        with tempfile.TemporaryDirectory() as directory:
+            root = Path(directory)
+            (root / "main.py").touch()
+            first = self.build_command(root, {"id": "worker-a", "port": 8190})
+            renamed = self.build_command(root, {
+                "id": "worker-a", "port": 9001, "name": "Renamed", "cuda_device": 3,
+            })
+            second = self.build_command(root, {"id": "worker-b", "port": 8191})
+            database = first[first.index("--database-url") + 1]
+            self.assertEqual(database, renamed[renamed.index("--database-url") + 1])
+            self.assertNotEqual(database, second[second.index("--database-url") + 1])
+            self.assertTrue(database.startswith("sqlite:///" + root.as_posix() + "/"))
+            self.assertTrue(Path(database.removeprefix("sqlite:///")).parent.is_dir())
+            self.assertNotIn("--disable-assets", first)
+
+    def test_database_uses_effective_user_or_base_directory(self):
+        with tempfile.TemporaryDirectory() as directory:
+            root = Path(directory)
+            (root / "main.py").touch()
+            for extra_args, expected in [
+                (f'--user-directory "{root / "custom user"}"', root / "custom user"),
+                (f'--base-directory "{root / "custom base"}"', root / "custom base" / "user"),
+            ]:
+                with self.subTest(extra_args=extra_args):
+                    cmd = self.build_command(root, {
+                        "id": "worker-a", "port": 8190, "extra_args": extra_args,
+                    })
+                    database = cmd[cmd.index("--database-url") + 1]
+                    self.assertTrue(database.startswith("sqlite:///" + expected.as_posix() + "/"))
+            cmd = self.build_command(root, runtime=Namespace(
+                database_url="sqlite:///master.db", user_directory=str(root / "runtime user"),
+            ))
+            database = cmd[cmd.index("--database-url") + 1]
+            self.assertTrue(database.startswith("sqlite:///" + (root / "runtime user").as_posix() + "/"))
+            self.assertNotEqual(database, "sqlite:///master.db")
+
+    def test_relative_database_directories_use_worker_cwd(self):
+        with tempfile.TemporaryDirectory() as directory:
+            root = Path(directory) / "ComfyUI"
+            root.mkdir()
+            (root / "main.py").touch()
+            launcher = Path(directory) / "launcher"
+            launcher.mkdir()
+            cases = [
+                (Namespace(database_url=None, user_directory="profiles"), "", root / "profiles"),
+                (Namespace(database_url=None, base_directory="data"), "", root / "data/user"),
+                (Namespace(database_url=None), "--user-directory=profiles", root / "profiles"),
+                (Namespace(database_url=None), "--base-directory data", root / "data/user"),
+            ]
+            for runtime, extra, expected in cases:
+                with self.subTest(runtime=runtime, extra=extra), \
+                     patch.object(os, "getcwd", return_value=str(launcher)):
+                    cmd = self.build_command(root, {
+                        "id": "worker-a", "port": 8190, "extra_args": extra,
+                    }, runtime)
+                    database = make_url(cmd[cmd.index("--database-url") + 1]).database
+                    self.assertEqual(Path(database).parent, expected / "distributed/workers")
+            self.assertFalse((launcher / "profiles").exists())
+            self.assertFalse((launcher / "data").exists())
+
+    def test_database_url_round_trips_special_characters_without_collisions(self):
+        with tempfile.TemporaryDirectory() as directory:
+            root = Path(directory)
+            (root / "main.py").touch()
+            for name in ["user?profile", "user%3Fprofile"]:
+                with self.subTest(name=name):
+                    user = root / name
+                    runtime = Namespace(database_url=None, user_directory=str(user))
+                    # SQLAlchemy 2.0 cannot round-trip '?' in a filename. Fail
+                    # clearly on those versions rather than silently sharing a DB.
+                    sample = (user / "test.db").as_posix()
+                    serialized = URL.create("sqlite", database=sample).render_as_string()
+                    if make_url(serialized).database != sample:
+                        with self.assertRaisesRegex(ValueError, "SQLAlchemy.*database path"):
+                            self.build_command(root, runtime=runtime)
+                        self.assertFalse(user.exists())
+                        continue
+                    databases = []
+                    for worker_id in ["worker-a", "worker-b"]:
+                        cmd = self.build_command(root, {"id": worker_id, "port": 8190}, runtime)
+                        url = cmd[cmd.index("--database-url") + 1]
+                        database = make_url(url).database
+                        self.assertEqual(Path(database).parent, user / "distributed/workers")
+                        engine = create_engine(url)
+                        try:
+                            with engine.connect() as connection:
+                                actual = connection.exec_driver_sql("PRAGMA database_list").one()[2]
+                                self.assertEqual(Path(actual), Path(database))
+                        finally:
+                            engine.dispose()
+                        databases.append(database)
+                    self.assertNotEqual(*databases)
+
+    def test_explicit_database_and_disabled_assets_are_preserved(self):
+        with tempfile.TemporaryDirectory() as directory:
+            root = Path(directory)
+            (root / "main.py").touch()
+            for extra in ["--database-url sqlite:///explicit.db", "--database-url=sqlite:///explicit.db", "--disable-assets"]:
+                with self.subTest(extra=extra):
+                    cmd = self.build_command(root, {"id": "worker-a", "port": 8190, "extra_args": extra})
+                    self.assertEqual(sum(arg.split("=")[0] == "--database-url" for arg in cmd), 0 if extra == "--disable-assets" else 1)
+                    self.assertFalse((root / "user").exists())
+
+    def test_older_comfyui_without_database_flag_keeps_existing_command(self):
+        with tempfile.TemporaryDirectory() as directory:
+            root = Path(directory)
+            (root / "main.py").touch()
+            cmd = self.build_command(root, runtime=Namespace())
+            self.assertNotIn("--database-url", cmd)
+            self.assertFalse((root / "user").exists())
+
+    def test_worker_id_cannot_escape_database_directory(self):
+        with tempfile.TemporaryDirectory() as directory:
+            root = Path(directory)
+            (root / "main.py").touch()
+            databases = []
+            for worker_id in ["../outside", "a/b", "a_b"]:
+                cmd = self.build_command(root, {"id": worker_id, "port": 8190})
+                path = Path(cmd[cmd.index("--database-url") + 1].removeprefix("sqlite:///"))
+                self.assertTrue(path.is_relative_to(root / "user"))
+                databases.append(path)
+            self.assertEqual(len(set(databases)), 3)
+
+    def test_extra_args_cannot_silently_override_the_configured_port(self):
+        with tempfile.TemporaryDirectory() as directory:
+            root = Path(directory)
+            (root / "main.py").touch()
+            for extra in ["--port 8189", "--port=8189"]:
+                with self.subTest(extra=extra), self.assertRaisesRegex(ValueError, "configured worker port"):
+                    self.build_command(root, {"id": "worker-a", "port": 8190, "extra_args": extra})
+
     def test_inherits_runtime_layout_args_for_desktop(self):
         builder = launch_builder_module.LaunchCommandBuilder()
         runtime_args = Namespace(
@@ -130,5 +289,64 @@ class LaunchCommandBuilderTests(unittest.TestCase):
         self.assertNotIn("--auto-launch", cmd)
 
 
+class ProcessLaunchPortTests(unittest.TestCase):
+    def test_launch_before_master_listens_uses_configured_master_port(self):
+        lifecycle_module = _load_process_module("lifecycle.py")
+        cli_args = types.ModuleType("comfy.cli_args")
+        cli_args.args = Namespace(port=8189)
+        for missing in [AttributeError("PromptServer has no port"), None]:
+            with self.subTest(missing=missing), tempfile.TemporaryDirectory() as directory:
+                manager = types.SimpleNamespace(
+                    find_comfy_root=lambda: directory,
+                    build_launch_command=lambda _worker, _root: ["python", "main.py"],
+                    processes={}, save_processes=lambda: None,
+                )
+                with patch.dict(sys.modules, {"comfy": types.ModuleType("comfy"), "comfy.cli_args": cli_args}), \
+                     patch.object(lifecycle_module, "get_server_port", side_effect=missing if isinstance(missing, Exception) else None, return_value=None), \
+                     patch.object(lifecycle_module, "validate_worker_port") as validate, \
+                     patch.object(lifecycle_module.subprocess, "Popen", return_value=types.SimpleNamespace(pid=1234)) as spawn:
+                    pid = lifecycle_module.ProcessLifecycle(manager).launch_worker({"id": "manual", "port": 8190})
+                validate.assert_called_once_with({"id": "manual", "port": 8190}, 8189, [])
+                spawn.assert_called_once()
+                self.assertEqual(pid, 1234)
+
+    def test_pre_listen_launch_still_rejects_the_configured_master_port(self):
+        lifecycle_module = _load_process_module("lifecycle.py")
+        cli_args = types.ModuleType("comfy.cli_args")
+        cli_args.args = Namespace(port=8189)
+        manager = types.SimpleNamespace(find_comfy_root=lambda: "/ComfyUI", processes={})
+        with patch.dict(sys.modules, {"comfy": types.ModuleType("comfy"), "comfy.cli_args": cli_args}), \
+             patch.object(lifecycle_module, "get_server_port", side_effect=AttributeError("port")), \
+             patch.object(lifecycle_module.subprocess, "Popen") as spawn:
+            with self.assertRaisesRegex(ValueError, "master port 8189"):
+                lifecycle_module.ProcessLifecycle(manager).launch_worker({"id": "manual", "port": 8189})
+        spawn.assert_not_called()
+
+    def test_conflict_is_rejected_before_building_or_spawning(self):
+        lifecycle_module = _load_process_module("lifecycle.py")
+        manager = types.SimpleNamespace(find_comfy_root=lambda: "/ComfyUI", processes={})
+        with patch.object(lifecycle_module.subprocess, "Popen") as spawn:
+            with self.assertRaisesRegex(ValueError, "master port 8189"):
+                lifecycle_module.ProcessLifecycle(manager).launch_worker({"id": "manual", "port": 8189})
+        spawn.assert_not_called()
+        self.assertEqual(manager.processes, {})
+
+    def test_available_port_reaches_existing_launch_path(self):
+        lifecycle_module = _load_process_module("lifecycle.py")
+        with tempfile.TemporaryDirectory() as directory:
+            manager = types.SimpleNamespace(
+                find_comfy_root=lambda: directory,
+                build_launch_command=lambda _worker, _root: ["python", "main.py", "--port", "8190"],
+                processes={}, save_processes=lambda: None,
+            )
+            with patch.object(lifecycle_module, "validate_worker_port") as validate, \
+                 patch.object(lifecycle_module.subprocess, "Popen", return_value=types.SimpleNamespace(pid=1234)) as spawn:
+                pid = lifecycle_module.ProcessLifecycle(manager).launch_worker({"id": "manual", "port": 8190})
+            validate.assert_called_once_with({"id": "manual", "port": 8190}, 8189, [])
+            spawn.assert_called_once()
+            self.assertEqual(pid, 1234)
+            self.assertEqual(manager.processes["manual"]["pid"], 1234)
+
+
 if __name__ == "__main__":
     unittest.main()

utils/config.py

@@ -2,10 +2,12 @@
 Configuration management for ComfyUI-Distributed.
 """
 import asyncio
+import copy
 import os
 import json
 from contextlib import asynccontextmanager
 from .logging import log
+from .secret_fields import is_secret_field_name as _is_secret_field_name
 
 # Import defaults for timeout fallbacks
 from .constants import HEARTBEAT_TIMEOUT
@@ -15,6 +17,52 @@ _config_cache = None
 _config_mtime = 0.0
 _config_lock = asyncio.Lock()
 
+_SERVERLESS_OBSOLETE_WORKER_FIELDS = {"host", "port", "listen_port", "cuda_device", "extra_args"}
+
+
+def _contains_serverless_secret(value):
+    if isinstance(value, dict):
+        return any(
+            (isinstance(key, str) and _is_secret_field_name(key))
+            or _contains_serverless_secret(item)
+            for key, item in value.items()
+        )
+    if isinstance(value, (list, tuple)):
+        return any(_contains_serverless_secret(item) for item in value)
+    return False
+
+
+def _normalize_serverless_workers(config):
+    """Remove obsolete local-worker fields without adding local defaults."""
+    if not isinstance(config, dict):
+        return config
+    workers = config.get("workers")
+    if isinstance(workers, list):
+        for worker in workers:
+            if isinstance(worker, dict) and worker.get("type") == "serverless":
+                for field in _SERVERLESS_OBSOLETE_WORKER_FIELDS:
+                    worker.pop(field, None)
+    return config
+
+
+def _validated_config_for_save(config):
+    """Return a safe normalized copy ready for gpu_config.json."""
+    if _contains_serverless_secret(config):
+        raise ValueError("API keys must be stored outside the config file")
+    saved = _normalize_serverless_workers(copy.deepcopy(config))
+    workers = saved.get("workers") if isinstance(saved, dict) else None
+    if isinstance(workers, list) and any(
+        isinstance(worker, dict) and worker.get("type") == "serverless" for worker in workers
+    ):
+        from .serverless_config import validate_serverless_worker
+        for index, worker in enumerate(workers):
+            if isinstance(worker, dict) and worker.get("type") == "serverless":
+                saved_worker = validate_serverless_worker(worker)
+                for field in _SERVERLESS_OBSOLETE_WORKER_FIELDS:
+                    saved_worker.pop(field, None)
+                workers[index] = saved_worker
+    return saved
+
 
 def _config_path():
     return CONFIG_FILE
@@ -62,7 +110,7 @@ def _merge_with_defaults(data, defaults):
         if key not in merged:
             merged[key] = value
 
-    return merged
+    return _normalize_serverless_workers(merged)
 
 
 def invalidate_config_cache():
@@ -97,11 +145,12 @@ def load_config():
     return _config_cache
 
 def save_config(config):
-    """Saves the configuration to file."""
+    """Saves normalized configuration without allowing API keys in the config file."""
     tmp_path = f"{_config_path()}.tmp"
     try:
+        saved_config = _validated_config_for_save(config)
         with open(tmp_path, 'w', encoding='utf-8') as f:
-            json.dump(config, f, indent=2)
+            json.dump(saved_config, f, indent=2)
             f.flush()
             os.fsync(f.fileno())
         os.replace(tmp_path, _config_path())
@@ -121,12 +170,21 @@ async def config_transaction():
     """Acquire config lock, yield loaded config, and save if changed."""
     async with _config_lock:
         config = load_config()
+        original_config = copy.deepcopy(config)
         original_snapshot = json.dumps(config, sort_keys=True)
-        yield config
+        try:
+            yield config
+        except BaseException:
+            if isinstance(config, dict):
+                config.clear()
+                config.update(original_config)
+            raise
         updated_snapshot = json.dumps(config, sort_keys=True)
-        if updated_snapshot != original_snapshot:
-            if not save_config(config):
-                raise RuntimeError("Failed to save config")
+        if updated_snapshot != original_snapshot and not save_config(config):
+            if isinstance(config, dict):
+                config.clear()
+                config.update(original_config)
+            raise RuntimeError("Failed to save config")
 
 def ensure_config_exists():
     """Creates default config file if it doesn't exist. Used by __init__.py"""

utils/constants.py

@@ -42,6 +42,17 @@ MEMORY_CLEAR_DELAY = 0.5
 # Batch processing
 MAX_BATCH = int(os.environ.get('COMFYUI_MAX_BATCH', '20'))  # Maximum items per batch to prevent timeouts/OOM (~100MB chunks for 512x512 PNGs)
 
+# Compressed worker -> master result transfer (DistributedCollector)
+# Hard cap on one multipart request body. Must not exceed the master's
+# --max-upload-size (ComfyUI default: 100 MiB), which rejects larger requests.
+TRANSFER_MAX_REQUEST_BYTES = int(os.environ.get('COMFYUI_DISTRIBUTED_TRANSFER_MAX_REQUEST_BYTES', str(96 * 1024 * 1024)))
+# Target media bytes per request when batching several frames into one
+# request; a single frame may exceed this up to the hard cap above.
+TRANSFER_MAX_CHUNK_BYTES = min(
+    int(os.environ.get('COMFYUI_DISTRIBUTED_TRANSFER_CHUNK_BYTES', str(32 * 1024 * 1024))),
+    TRANSFER_MAX_REQUEST_BYTES,
+)
+
 # Heartbeat monitoring
 HEARTBEAT_INTERVAL = float(os.environ.get('COMFYUI_HEARTBEAT_INTERVAL', '10'))  # Heartbeat/check interval in seconds
 HEARTBEAT_TIMEOUT = int(os.environ.get('COMFYUI_HEARTBEAT_TIMEOUT', '60'))  # Worker heartbeat timeout in seconds (default 60s)

utils/network.py

@@ -87,6 +87,8 @@ def _split_host_and_port(host):
 
 def build_worker_url(worker, endpoint=""):
     """Construct the worker base URL with optional endpoint."""
+    if worker.get("type") == "serverless":
+        raise ValueError("Serverless workers have no ComfyUI worker URL")
     host = (worker.get("host") or "").strip()
     port = int(worker.get("port", worker.get("listen_port", 8188)) or 8188)
 

utils/secret_fields.py

@@ -0,0 +1,9 @@
+"""Shared classification for credential-bearing configuration fields."""
+
+
+def is_secret_field_name(key: object) -> bool:
+    """Return whether a field name identifies an API key or credential."""
+    if not isinstance(key, str):
+        return False
+    normalized = "".join(character for character in key.casefold() if character.isalnum())
+    return normalized in {"apikey", "clearapikey"} or "credential" in normalized

utils/serverless_config.py

@@ -0,0 +1,451 @@
+"""Validation and private storage for Runpod serverless worker settings.
+
+Secret storage is supported only on POSIX masters. The module remains
+importable elsewhere so ordinary worker configuration and redaction continue
+to work, but secret-store operations fail explicitly without POSIX locking.
+"""
+
+from __future__ import annotations
+
+import copy
+import json
+import os
+import re
+import secrets
+import stat
+import threading
+from contextlib import contextmanager
+from pathlib import Path
+from typing import Iterator
+
+from .secret_fields import is_secret_field_name
+
+try:
+    import fcntl
+except ImportError:  # Windows and other platforms without POSIX file locking.
+    fcntl = None
+
+
+class ServerlessConfigError(ValueError):
+    """A serverless worker configuration is invalid."""
+
+
+class SecretStoreError(RuntimeError):
+    """The secret store could not be accessed safely."""
+
+
+_ENDPOINT_ID_RE = re.compile(r"[A-Za-z0-9_-]{1,200}", re.ASCII)
+_UNSUPPORTED_SECRET_STORE_MESSAGE = (
+    "Serverless credential storage is currently supported on POSIX masters only"
+)
+# Images per run is also this worker's effective parallelism: every image job
+# is submitted at once (the runtime's fixed PER_WORKER_JOB_LIMIT equals this),
+# and the Runpod endpoint's max workers decides how many actually run together.
+MAX_JOBS_PER_RUN = 16
+_NUMERIC_FIELDS = {
+    "jobs_per_run": (1, MAX_JOBS_PER_RUN, 1),
+    "timeout_seconds": (30, 86400, 1800),
+}
+# Older configs saved a separate concurrency setting. It is accepted so they
+# still load, then dropped: PER_WORKER_JOB_LIMIT replaces it.
+_LEGACY_IGNORED_FIELDS = ("concurrency",)
+_THREAD_LOCKS: dict[str, threading.Lock] = {}
+_THREAD_LOCKS_GUARD = threading.Lock()
+
+
+def validate_serverless_worker(worker: dict) -> dict:
+    """Return a validated copy of a Runpod serverless worker record.
+
+    Provider credentials are intentionally not required here; they are stored
+    separately by :class:`SecretStore`.
+    """
+    if not isinstance(worker, dict):
+        raise ServerlessConfigError("worker must be an object")
+
+    try:
+        result = copy.deepcopy(worker)
+    except Exception:
+        raise ServerlessConfigError("worker must be copyable") from None
+
+    worker_id = result.get("id")
+    if not isinstance(worker_id, str) or not worker_id.strip():
+        raise ServerlessConfigError("id must be a non-empty string")
+
+    endpoint_id = result.get("endpoint_id")
+    if not isinstance(endpoint_id, str) or not _ENDPOINT_ID_RE.fullmatch(endpoint_id):
+        raise ServerlessConfigError(
+            "Endpoint ID must be just the Runpod endpoint ID (letters, numbers, - or _), not a URL"
+        )
+
+    if result.get("type", "serverless") != "serverless":
+        raise ServerlessConfigError("type must be serverless")
+    if result.get("provider", "runpod") != "runpod":
+        raise ServerlessConfigError("provider is not supported")
+    if "enabled" in result and type(result["enabled"]) is not bool:
+        raise ServerlessConfigError("enabled must be a boolean")
+
+    for field, (minimum, maximum, default) in _NUMERIC_FIELDS.items():
+        value = result.get(field, default)
+        if type(value) is not int or not minimum <= value <= maximum:
+            raise ServerlessConfigError(f"{field} must be an integer from {minimum} to {maximum}")
+        result[field] = value
+    for field in _LEGACY_IGNORED_FIELDS:
+        result.pop(field, None)
+
+    result["type"] = "serverless"
+    result["provider"] = "runpod"
+    return result
+
+
+def _thread_lock_for(path: str) -> threading.Lock:
+    with _THREAD_LOCKS_GUARD:
+        lock = _THREAD_LOCKS.get(path)
+        if lock is None:
+            lock = threading.Lock()
+            _THREAD_LOCKS[path] = lock
+        return lock
+
+
+class SecretStore:
+    """Atomically persist worker-id to API-key mappings in a private JSON file."""
+
+    def __init__(self, path: Path):
+        self.path = Path(path)
+
+    def get(self, worker_id: str) -> str | None:
+        self._require_supported()
+        worker_id = self._validate_worker_id(worker_id)
+        try:
+            with self._locked(create_parent=False) as (parent_fd, filename):
+                data = self._read_mapping(parent_fd, filename)
+                return data.get(worker_id)
+        except FileNotFoundError:
+            return None
+        except SecretStoreError:
+            raise
+        except Exception:
+            raise SecretStoreError("Unable to access secret store") from None
+
+    def set(self, worker_id: str, key: str) -> None:
+        self._require_supported()
+        worker_id = self._validate_worker_id(worker_id)
+        if (
+            not isinstance(key, str)
+            or not key
+            or len(key) > 4096
+            or "\r" in key
+            or "\n" in key
+        ):
+            raise SecretStoreError("secret must be 1 to 4096 characters and contain no CR or LF")
+        try:
+            with self._locked(create_parent=True) as (parent_fd, filename):
+                data = self._read_mapping(parent_fd, filename)
+                data[worker_id] = key
+                self._write_mapping(parent_fd, filename, data)
+        except SecretStoreError:
+            raise
+        except Exception:
+            raise SecretStoreError("Unable to access secret store") from None
+
+    def delete(self, worker_id: str) -> None:
+        self._require_supported()
+        worker_id = self._validate_worker_id(worker_id)
+        try:
+            with self._locked(create_parent=False) as (parent_fd, filename):
+                data = self._read_mapping(parent_fd, filename)
+                if worker_id in data:
+                    del data[worker_id]
+                    self._write_mapping(parent_fd, filename, data)
+        except FileNotFoundError:
+            return
+        except SecretStoreError:
+            raise
+        except Exception:
+            raise SecretStoreError("Unable to access secret store") from None
+
+    def has(self, worker_id: str) -> bool:
+        return self.get(worker_id) is not None
+
+    @staticmethod
+    def _require_supported() -> None:
+        # Never substitute a weaker Windows store: all operations retain the
+        # dir_fd/O_NOFOLLOW and flock protections implemented below.
+        if os.name != "posix" or fcntl is None:
+            raise SecretStoreError(_UNSUPPORTED_SECRET_STORE_MESSAGE)
+
+    @staticmethod
+    def _validate_worker_id(worker_id: str) -> str:
+        if not isinstance(worker_id, str) or not worker_id.strip():
+            raise SecretStoreError("worker_id must be a non-empty string")
+        return worker_id
+
+    def _absolute_path(self) -> Path:
+        path = self.path
+        if ".." in path.parts:
+            raise SecretStoreError("unsafe secret store path")
+        if not path.is_absolute():
+            path = Path.cwd() / path
+        if len(path.parts) < 2 or path.name in ("", ".", ".."):
+            raise SecretStoreError("unsafe secret store path")
+        return path
+
+    @contextmanager
+    def _locked(self, create_parent: bool) -> Iterator[tuple[int, str]]:
+        lock_api = fcntl
+        if os.name != "posix" or lock_api is None:
+            raise SecretStoreError(_UNSUPPORTED_SECRET_STORE_MESSAGE)
+        path = self._absolute_path()
+        filename = path.name
+        lock_name = f".{filename}.lock"
+        thread_lock = _thread_lock_for(str(path))
+
+        with thread_lock:
+            parent_fd = self._open_parent(path, create=create_parent)
+            lock_fd = None
+            try:
+                flags = os.O_RDWR | os.O_CREAT | os.O_CLOEXEC | os.O_NOFOLLOW
+                lock_fd = os.open(lock_name, flags, 0o600, dir_fd=parent_fd)
+                lock_stat = os.fstat(lock_fd)
+                if not stat.S_ISREG(lock_stat.st_mode):
+                    raise SecretStoreError("unsafe secret store lock")
+                os.fchmod(lock_fd, 0o600)
+                lock_api.flock(lock_fd, lock_api.LOCK_EX)
+                self._check_target(parent_fd, filename)
+                yield parent_fd, filename
+            except SecretStoreError:
+                raise
+            except Exception:
+                raise SecretStoreError("Unable to access secret store") from None
+            finally:
+                if lock_fd is not None:
+                    try:
+                        lock_api.flock(lock_fd, lock_api.LOCK_UN)
+                    except OSError:
+                        pass
+                    os.close(lock_fd)
+                os.close(parent_fd)
+
+    @staticmethod
+    def _open_parent(path: Path, create: bool) -> int:
+        parts = path.parts
+        current_fd = os.open(path.anchor, os.O_RDONLY | os.O_DIRECTORY | os.O_CLOEXEC)
+        try:
+            for part in parts[1:-1]:
+                created = False
+                try:
+                    next_fd = os.open(
+                        part,
+                        os.O_RDONLY | os.O_DIRECTORY | os.O_CLOEXEC | os.O_NOFOLLOW,
+                        dir_fd=current_fd,
+                    )
+                except FileNotFoundError:
+                    if not create:
+                        raise
+                    try:
+                        os.mkdir(part, 0o700, dir_fd=current_fd)
+                        created = True
+                    except FileExistsError:
+                        pass
+                    next_fd = os.open(
+                        part,
+                        os.O_RDONLY | os.O_DIRECTORY | os.O_CLOEXEC | os.O_NOFOLLOW,
+                        dir_fd=current_fd,
+                    )
+                if created:
+                    os.fchmod(next_fd, 0o700)
+                os.close(current_fd)
+                current_fd = next_fd
+            return current_fd
+        except Exception:
+            os.close(current_fd)
+            raise
+
+    @staticmethod
+    def _check_target(parent_fd: int, filename: str) -> None:
+        try:
+            target_stat = os.stat(filename, dir_fd=parent_fd, follow_symlinks=False)
+        except FileNotFoundError:
+            return
+        if not stat.S_ISREG(target_stat.st_mode):
+            raise SecretStoreError("unsafe secret store file")
+
+    @classmethod
+    def _read_mapping(cls, parent_fd: int, filename: str) -> dict[str, str]:
+        cls._check_target(parent_fd, filename)
+        try:
+            fd = os.open(
+                filename,
+                os.O_RDONLY | os.O_CLOEXEC | os.O_NOFOLLOW,
+                dir_fd=parent_fd,
+            )
+        except FileNotFoundError:
+            return {}
+        except Exception:
+            raise SecretStoreError("Unable to access secret store") from None
+
+        try:
+            file_stat = os.fstat(fd)
+            if not stat.S_ISREG(file_stat.st_mode):
+                raise SecretStoreError("unsafe secret store file")
+            os.fchmod(fd, 0o600)
+            with os.fdopen(fd, "rb") as stream:
+                raw = stream.read()
+            try:
+                mapping = json.loads(raw.decode("utf-8"), object_pairs_hook=cls._unique_object)
+            except Exception:
+                raise SecretStoreError("secret store is corrupt") from None
+            if not isinstance(mapping, dict) or any(
+                not isinstance(worker_id, str)
+                or not worker_id.strip()
+                or not isinstance(key, str)
+                or not key
+                for worker_id, key in mapping.items()
+            ):
+                raise SecretStoreError("secret store is corrupt")
+            return mapping
+        except SecretStoreError:
+            raise
+        except Exception:
+            raise SecretStoreError("Unable to access secret store") from None
+        finally:
+            try:
+                os.close(fd)
+            except OSError:
+                pass
+
+    @staticmethod
+    def _unique_object(pairs: list[tuple[str, object]]) -> dict[str, object]:
+        result: dict[str, object] = {}
+        for key, value in pairs:
+            if key in result:
+                raise ValueError("duplicate key")
+            result[key] = value
+        return result
+
+    @staticmethod
+    def _write_mapping(parent_fd: int, filename: str, mapping: dict[str, str]) -> None:
+        payload = json.dumps(mapping, ensure_ascii=False, sort_keys=True, separators=(",", ":")).encode("utf-8")
+        temp_name = f".{filename}.{secrets.token_hex(12)}.tmp"
+        temp_fd = None
+        try:
+            flags = os.O_WRONLY | os.O_CREAT | os.O_EXCL | os.O_CLOEXEC | os.O_NOFOLLOW
+            temp_fd = os.open(temp_name, flags, 0o600, dir_fd=parent_fd)
+            os.fchmod(temp_fd, 0o600)
+            with os.fdopen(temp_fd, "wb") as stream:
+                temp_fd = None
+                stream.write(payload)
+                stream.flush()
+                os.fsync(stream.fileno())
+            SecretStore._check_target(parent_fd, filename)
+            os.replace(temp_name, filename, src_dir_fd=parent_fd, dst_dir_fd=parent_fd)
+            os.fsync(parent_fd)
+        except SecretStoreError:
+            raise
+        except Exception:
+            raise SecretStoreError("Unable to access secret store") from None
+        finally:
+            if temp_fd is not None:
+                try:
+                    os.close(temp_fd)
+                except OSError:
+                    pass
+            try:
+                os.unlink(temp_name, dir_fd=parent_fd)
+            except OSError:
+                pass
+
+
+class ServerlessSecretChanges:
+    """Apply serverless secret changes and restore them unless committed.
+
+    Use this around the associated config transaction so a failed config save
+    compensates any secret-store writes or deletions made along the way.
+    """
+
+    def __init__(self):
+        self._originals: dict[tuple[int, str], tuple[SecretStore, str, str | None]] = {}
+        self._mutations: list[tuple[int, str]] = []
+        self._committed = False
+
+    def __enter__(self) -> "ServerlessSecretChanges":
+        return self
+
+    def __exit__(self, _exc_type, _exc_value, _traceback) -> bool:
+        if not self._committed:
+            self.rollback()
+        return False
+
+    def capture(self, store: SecretStore, worker_id: str) -> str | None:
+        """Capture and return the original key once per store/worker pair."""
+        mutation_id = (id(store), worker_id)
+        if mutation_id not in self._originals:
+            self._originals[mutation_id] = (store, worker_id, store.get(worker_id))
+        return self._originals[mutation_id][2]
+
+    def set(self, store: SecretStore, worker_id: str, key: str) -> None:
+        self._prepare_mutation(store, worker_id)
+        store.set(worker_id, key)
+
+    def delete(self, store: SecretStore, worker_id: str) -> None:
+        self._prepare_mutation(store, worker_id)
+        store.delete(worker_id)
+
+    def commit(self) -> None:
+        """Keep the secret changes after the corresponding config save."""
+        self._committed = True
+
+    def rollback(self) -> None:
+        """Best-effort restoration without masking the original route error."""
+        for mutation_id in reversed(self._mutations):
+            store, worker_id, prior_secret = self._originals[mutation_id]
+            try:
+                if prior_secret is None:
+                    store.delete(worker_id)
+                else:
+                    store.set(worker_id, prior_secret)
+            except Exception:
+                pass
+        self._mutations.clear()
+
+    def _prepare_mutation(self, store: SecretStore, worker_id: str) -> None:
+        self.capture(store, worker_id)
+        mutation_id = (id(store), worker_id)
+        if mutation_id not in self._mutations:
+            # Record before applying: a store operation may fail after replacing
+            # its file, so the exception path must still attempt compensation.
+            self._mutations.append(mutation_id)
+
+
+def _redact_credentials(value):
+    if isinstance(value, dict):
+        redacted = {}
+        for key, item in value.items():
+            if is_secret_field_name(key):
+                continue
+            redacted[key] = _redact_credentials(item)
+        return redacted
+    if isinstance(value, list):
+        return [_redact_credentials(item) for item in value]
+    if isinstance(value, tuple):
+        return tuple(_redact_credentials(item) for item in value)
+    return value
+
+
+def public_config(config, store: SecretStore):
+    """Return a deep-copied public configuration with credentials removed."""
+    result = _redact_credentials(copy.deepcopy(config))
+    if not isinstance(result, dict):
+        return result
+
+    workers = result.get("workers")
+    if isinstance(workers, list):
+        for worker in workers:
+            if isinstance(worker, dict) and worker.get("type") == "serverless":
+                worker_id = worker.get("id")
+                configured = (
+                    store.has(worker_id)
+                    if isinstance(worker_id, str) and worker_id.strip()
+                    else False
+                )
+                worker["api_key_configured"] = configured
+    return result

utils/transfer_codec.py

@@ -0,0 +1,411 @@
+"""
+Compressed worker -> master image transfer.
+
+Workers encode their IMAGE batch with one of the formats below and POST it to
+the master as multipart/form-data chunks; the master decodes each chunk back
+into per-frame tensors. The goal is to cut network egress (e.g. cloud workers
+returning results to a local master), so formats range from bit-exact
+lossless to strongly compressed video.
+
+Formats
+-------
+legacy_png  Original behaviour: one JSON request per frame, uncompressed PNG
+            in base64. Kept for compatibility with unmodified masters.
+png         Lossless PNG per frame, sent as binary.
+ffv1        Lossless FFV1 video for the whole batch (good for frame sequences).
+jpeg, webp  Lossy per-frame stills.
+h264, h265, av1
+            Lossy video for the whole batch. Smallest by far for video
+            frame batches, where consecutive frames are similar.
+
+All formats quantize to 8-bit exactly like the legacy path did, so the
+lossless formats reproduce the legacy master tensors bit-for-bit.
+"""
+import io
+import math
+import os
+
+import numpy as np
+from PIL import Image
+
+LEGACY_FORMAT = "legacy_png"
+IMAGE_FORMATS = ("png", "jpeg", "webp")
+VIDEO_FORMATS = ("ffv1", "h264", "h265", "av1")
+LOSSLESS_FORMATS = (LEGACY_FORMAT, "png", "ffv1")
+TRANSFER_FORMATS = (LEGACY_FORMAT, "png", "ffv1", "jpeg", "webp", "h264", "h265", "av1")
+
+DEFAULT_TRANSFER_FORMAT = LEGACY_FORMAT
+DEFAULT_TRANSFER_QUALITY = 90
+
+TRANSFER_FORMAT_TOOLTIP = (
+    "How workers send images back to the master. "
+    "legacy_png: original uncompressed PNG (largest). "
+    "png / ffv1: lossless, identical result. "
+    "jpeg / webp: lossy stills. "
+    "h264 / h265 / av1: lossy video of the whole batch, smallest for frame sequences."
+)
+TRANSFER_QUALITY_TOOLTIP = (
+    "Quality for lossy transfer formats (ignored by lossless ones). "
+    "JPEG/WebP use it directly; video codecs map it to CRF "
+    "(90 -> h264/h265 CRF 13, av1 CRF 16)."
+)
+
+# encoder name, max CRF, container-friendly pixel format
+_VIDEO_CODECS = {
+    "ffv1": ("ffv1", None, "bgr0"),
+    "h264": ("libx264", 51, "yuv420p"),
+    "h265": ("libx265", 51, "yuv420p"),
+    "av1": ("libsvtav1", 63, "yuv420p"),
+}
+_VIDEO_RATE = 24
+# Upper bound on frames per video chunk, so one request never holds an
+# unbounded batch even when frames compress extremely well.
+MAX_VIDEO_CHUNK_FRAMES = 240
+# When sizing the next video chunk from observed bytes/frame, aim this far
+# below the limit so ordinary variation does not force a re-encode.
+VIDEO_CHUNK_SIZE_HEADROOM = 0.85
+
+
+class TransferCodecError(ValueError):
+    """Raised when a transfer payload cannot be encoded or decoded."""
+
+
+class FrameTooLargeError(TransferCodecError):
+    """A single encoded frame does not fit in one request.
+
+    Raised by encode_chunks before anything has been yielded for that frame;
+    callers that materialize all chunks first can therefore fail without
+    having delivered a partial batch.
+    """
+
+
+def normalize_format(value):
+    fmt = str(value or DEFAULT_TRANSFER_FORMAT).strip().lower()
+    if fmt not in TRANSFER_FORMATS:
+        raise TransferCodecError(
+            f"Unknown transfer format '{value}'. Expected one of: {', '.join(TRANSFER_FORMATS)}"
+        )
+    return fmt
+
+
+def normalize_quality(value):
+    try:
+        quality = int(value)
+    except (TypeError, ValueError):
+        quality = DEFAULT_TRANSFER_QUALITY
+    return max(1, min(100, quality))
+
+
+def quality_to_crf(quality, max_crf):
+    """Map 1-100 quality onto a codec CRF scale (0 = lossless/best).
+
+    The curve is chosen so the same quality number looks roughly the same
+    across JPEG/WebP and video codecs: 90 -> CRF 13 (h264/h265), 16 (av1);
+    80 -> 19 / 24; 100 -> 0.
+    """
+    quality = normalize_quality(quality)
+    return int(round(max_crf * (1.0 - quality / 100.0) ** 0.6))
+
+
+def tensor_batch_to_uint8(images):
+    """IMAGE tensor [B,H,W,C] float 0..1 -> uint8 numpy [B,H,W,3].
+
+    Uses the same truncating quantization as utils.image.tensor_to_pil so that
+    lossless formats reproduce the legacy transfer exactly, but clips first so
+    out-of-range values no longer wrap around.
+    """
+    arr = images.detach().cpu().float().numpy()
+    if arr.ndim == 3:
+        arr = arr[None, ...]
+    if arr.ndim != 4:
+        raise TransferCodecError(f"Expected IMAGE tensor [B,H,W,C], got shape {tuple(arr.shape)}")
+    channels = arr.shape[-1]
+    if channels == 1:
+        arr = np.repeat(arr, 3, axis=-1)
+    elif channels >= 3:
+        arr = arr[..., :3]
+    else:
+        raise TransferCodecError(f"Unsupported channel count {channels}")
+    return np.ascontiguousarray(np.clip(255.0 * arr, 0, 255).astype(np.uint8))
+
+
+def uint8_frame_to_tensor_array(frame):
+    """uint8 [H,W,3] -> float32 [1,H,W,3] numpy, matching utils.image.pil_to_tensor."""
+    return (frame.astype(np.float32) / 255.0)[None, ...]
+
+
+# --------------------------------------------------------------------------- #
+# Still images
+# --------------------------------------------------------------------------- #
+
+def encode_image_frame(frame, fmt, quality):
+    img = Image.fromarray(frame)
+    quality = normalize_quality(quality)
+    buf = io.BytesIO()
+    if fmt == "png":
+        img.save(buf, format="PNG", compress_level=4)  # ~same size as 6, 2x faster
+    elif fmt == "jpeg":
+        img.save(buf, format="JPEG", quality=quality, subsampling=0 if quality >= 90 else 2)
+    elif fmt == "webp":
+        img.save(buf, format="WEBP", quality=quality, method=4)
+    else:
+        raise TransferCodecError(f"'{fmt}' is not a still-image transfer format")
+    return buf.getvalue()
+
+
+def decode_image_frame(data):
+    try:
+        with Image.open(io.BytesIO(data)) as img:
+            return np.asarray(img.convert("RGB"), dtype=np.uint8)
+    except Exception as exc:
+        raise TransferCodecError(f"Failed to decode image frame: {exc}") from exc
+
+
+# --------------------------------------------------------------------------- #
+# Video
+# --------------------------------------------------------------------------- #
+
+def _import_av():
+    # SVT-AV1 prints a banner per encoder instance unless told otherwise.
+    os.environ.setdefault("SVT_LOG", "1")
+    try:
+        import av  # PyAV ships with ComfyUI
+    except ImportError as exc:
+        raise TransferCodecError("PyAV ('av') is required for video transfer formats") from exc
+    return av
+
+
+def video_codec_available(fmt):
+    if fmt not in _VIDEO_CODECS:
+        return False
+    try:
+        av = _import_av()
+        av.codec.Codec(_VIDEO_CODECS[fmt][0], "w")
+        return True
+    except Exception:
+        return False
+
+
+def _padded_size(fmt, pix_fmt, width, height):
+    """Encoder-friendly frame size; the decoder crops back to width x height.
+
+    4:2:0 needs even dimensions, and libx265 crashes on frames smaller than
+    its 64px CTU, so pad up to whichever is larger.
+    """
+    if pix_fmt == "yuv420p":
+        width, height = width + width % 2, height + height % 2
+    if fmt == "h265":
+        width, height = max(width, 64), max(height, 64)
+    return width, height
+
+
+def _pad_to(frame, width, height):
+    h, w = frame.shape[:2]
+    if h == height and w == width:
+        return frame
+    return np.pad(frame, ((0, height - h), (0, width - w), (0, 0)), mode="edge")
+
+
+class _VideoChunkWriter:
+    def __init__(self, fmt, quality, width, height):
+        av = _import_av()
+        self._av = av
+        codec_name, max_crf, pix_fmt = _VIDEO_CODECS[fmt]
+        self.fmt = fmt
+        self.pix_fmt = pix_fmt
+        self.width, self.height = _padded_size(fmt, pix_fmt, width, height)
+        self.buffer = io.BytesIO()
+        self.container = av.open(self.buffer, mode="w", format="matroska")
+        self.stream = self.container.add_stream(codec_name, rate=_VIDEO_RATE)
+        self.stream.width = self.width
+        self.stream.height = self.height
+        self.stream.pix_fmt = pix_fmt
+        options = {}
+        if max_crf is not None:
+            options["crf"] = str(quality_to_crf(quality, max_crf))
+        if fmt == "h264":
+            options["preset"] = "medium"
+        elif fmt == "h265":
+            options["preset"] = "fast"
+            options["x265-params"] = "log-level=error"
+        elif fmt == "av1":
+            options["preset"] = "8"
+        elif fmt == "ffv1":
+            options["level"] = "3"
+            options["slicecrc"] = "0"
+        self.stream.options = options
+        self.count = 0
+
+    def add(self, frame):
+        frame = _pad_to(frame, self.width, self.height)
+        vf = self._av.VideoFrame.from_ndarray(frame, format="rgb24")
+        for packet in self.stream.encode(vf):
+            self.container.mux(packet)
+        self.count += 1
+
+    def bytes_so_far(self):
+        return self.buffer.tell()
+
+    def close(self):
+        for packet in self.stream.encode():
+            self.container.mux(packet)
+        self.container.close()
+        return self.buffer.getvalue()
+
+
+def decode_video(data, width, height, expected_frames=None):
+    av = _import_av()
+    frames = []
+    try:
+        with av.open(io.BytesIO(data), mode="r") as container:
+            for vf in container.decode(video=0):
+                arr = vf.to_ndarray(format="rgb24")
+                frames.append(np.ascontiguousarray(arr[:height, :width]))
+    except TransferCodecError:
+        raise
+    except Exception as exc:
+        raise TransferCodecError(f"Failed to decode video chunk: {exc}") from exc
+    if expected_frames is not None and len(frames) != expected_frames:
+        raise TransferCodecError(
+            f"Video chunk decoded to {len(frames)} frames, expected {expected_frames}"
+        )
+    return frames
+
+
+# --------------------------------------------------------------------------- #
+# Chunking
+# --------------------------------------------------------------------------- #
+
+def encode_chunks(frames, fmt, quality, max_chunk_bytes, max_frame_bytes=None):
+    """Yield transfer chunks for a uint8 frame batch [B,H,W,3].
+
+    Each chunk is a dict:
+        {"format", "start_index", "count", "width", "height", "parts": [bytes, ...]}
+    Image formats carry one part per frame; video formats carry one part
+    (a Matroska file) holding `count` frames.
+
+    Size guarantees, measured on the finalized bytes (after encoder flush and
+    muxer finalization, not on encoder buffers):
+
+    * a chunk holding more than one frame never exceeds `max_chunk_bytes`;
+    * a chunk holding a single frame may exceed `max_chunk_bytes` but never
+      `max_frame_bytes` (defaults to `max_chunk_bytes`).
+
+    A frame that cannot fit in `max_frame_bytes` even on its own raises
+    FrameTooLargeError. Video chunks that come out too large are re-encoded
+    with fewer frames.
+    """
+    fmt = normalize_format(fmt)
+    if fmt == LEGACY_FORMAT:
+        raise TransferCodecError("legacy_png is sent through the JSON path, not encode_chunks")
+    total = int(frames.shape[0])
+    if total == 0:
+        return
+    height, width = int(frames.shape[1]), int(frames.shape[2])
+    max_chunk_bytes = max(1, int(max_chunk_bytes))
+    max_frame_bytes = max_chunk_bytes if max_frame_bytes is None else max(max_chunk_bytes, int(max_frame_bytes))
+
+    def _chunk(start, parts, count):
+        return {
+            "format": fmt,
+            "start_index": start,
+            "count": count,
+            "width": width,
+            "height": height,
+            "parts": parts,
+        }
+
+    def _too_large(index, size):
+        return FrameTooLargeError(
+            f"Frame {index} encodes to {size} bytes as {fmt}, above the {max_frame_bytes}-byte request limit. "
+            "Use a lossy format or lower quality, or raise the master's --max-upload-size together with "
+            "COMFYUI_DISTRIBUTED_TRANSFER_MAX_REQUEST_BYTES."
+        )
+
+    if fmt in IMAGE_FORMATS:
+        start, parts, size = 0, [], 0
+        for i in range(total):
+            data = encode_image_frame(frames[i], fmt, quality)
+            if len(data) > max_frame_bytes:
+                raise _too_large(i, len(data))
+            if parts and size + len(data) > max_chunk_bytes:
+                yield _chunk(start, parts, len(parts))
+                start, parts, size = i, [], 0
+            parts.append(data)
+            size += len(data)
+        if parts:
+            yield _chunk(start, parts, len(parts))
+        return
+
+    start = 0
+    budget = MAX_VIDEO_CHUNK_FRAMES
+    while start < total:
+        want = min(budget, total - start)
+        data, count = _encode_video_range(frames, start, want, fmt, quality, width, height, max_chunk_bytes)
+        if len(data) <= max_chunk_bytes or (count == 1 and len(data) <= max_frame_bytes):
+            yield _chunk(start, [data], count)
+            start += count
+            per_frame = len(data) / count
+            budget = max(1, min(MAX_VIDEO_CHUNK_FRAMES, int(max_chunk_bytes * VIDEO_CHUNK_SIZE_HEADROOM / per_frame)))
+            continue
+        if count == 1:
+            raise _too_large(start, len(data))
+        # Finalized chunk overshot: retry this range with proportionally fewer
+        # frames. Strictly fewer than `count`, so this always terminates.
+        estimate = int(count * max_chunk_bytes * VIDEO_CHUNK_SIZE_HEADROOM / len(data))
+        budget = max(1, min(count - 1, estimate))
+
+
+def _encode_video_range(frames, start, count, fmt, quality, width, height, stop_after_bytes):
+    """Encode frames[start:start+count] as one finalized video.
+
+    Stops feeding frames early once the muxed output already exceeds
+    `stop_after_bytes`, since the chunk is then known to be too large and will
+    be re-encoded smaller; this bounds wasted work. Encoder lookahead means the
+    pre-flush size underestimates the final size, so the caller must still
+    check the returned (finalized) bytes. Returns (bytes, frames_encoded).
+    """
+    writer = _VideoChunkWriter(fmt, quality, width, height)
+    for i in range(start, start + count):
+        writer.add(frames[i])
+        if writer.bytes_so_far() > stop_after_bytes:
+            break
+    return writer.close(), writer.count
+
+
+def decode_chunk(envelope, parts):
+    """Decode one received chunk into a list of uint8 [H,W,3] frames."""
+    fmt = normalize_format(envelope.get("format"))
+    if fmt == LEGACY_FORMAT:
+        raise TransferCodecError("legacy_png chunks are not sent as multipart")
+    count = envelope.get("count")
+    width = envelope.get("width")
+    height = envelope.get("height")
+    for name, value in (("count", count), ("width", width), ("height", height)):
+        if not isinstance(value, int) or isinstance(value, bool) or value <= 0:
+            raise TransferCodecError(f"envelope.{name}: expected positive integer")
+    if not parts:
+        raise TransferCodecError("chunk has no media parts")
+
+    if fmt in IMAGE_FORMATS:
+        if len(parts) != count:
+            raise TransferCodecError(f"expected {count} image parts, got {len(parts)}")
+        frames = [decode_image_frame(p) for p in parts]
+    else:
+        if len(parts) != 1:
+            raise TransferCodecError(f"expected 1 video part, got {len(parts)}")
+        frames = decode_video(parts[0], width, height, expected_frames=count)
+
+    for frame in frames:
+        if frame.shape[0] != height or frame.shape[1] != width:
+            raise TransferCodecError(
+                f"decoded frame is {frame.shape[1]}x{frame.shape[0]}, expected {width}x{height}"
+            )
+    return frames
+
+
+def describe_ratio(sent_bytes, raw_bytes):
+    if sent_bytes <= 0:
+        return "n/a"
+    ratio = raw_bytes / sent_bytes
+    return f"{ratio:.1f}x" if math.isfinite(ratio) else "n/a"

web/apiClient.js

@@ -7,7 +7,7 @@ export function createApiClient(baseUrl) {
     const request = async (
         endpoint,
         options = {},
-        { retries = TIMEOUTS.MAX_RETRIES, retry = true } = {},
+        { retries = TIMEOUTS.MAX_RETRIES, retry = true, redactErrors = false } = {},
     ) => {
         const maxAttempts = retry ? retries : 1;
         let lastError;
@@ -36,7 +36,7 @@ export function createApiClient(baseUrl) {
                 return await response.json();
             } catch (error) {
                 lastError = error;
-                console.log(`API Error (attempt ${attempt + 1}/${maxAttempts}): ${endpoint} - ${error.message}`);
+                console.log(`API Error (attempt ${attempt + 1}/${maxAttempts}): ${endpoint} - ${redactErrors ? "[redacted]" : error.message}`);
                 if (attempt < maxAttempts - 1) {
                     await new Promise(resolve => setTimeout(resolve, delay));
                     delay *= 2; // Exponential backoff
@@ -86,9 +86,35 @@ export function createApiClient(baseUrl) {
         },
         
         async updateWorker(workerId, data) {
-            return request('/distributed/config/update_worker', {
+            const apiKey = data?.api_key;
+            try {
+                return await request('/distributed/config/update_worker', {
+                    method: 'POST',
+                    body: JSON.stringify({ worker_id: workerId, ...data })
+                }, { retry: false, redactErrors: Boolean(apiKey) });
+            } catch (error) {
+                if (apiKey && typeof error?.message === "string") {
+                    error.message = error.message.split(apiKey).join("[redacted]");
+                }
+                throw error;
+            }
+        },
+
+        async testServerlessWorker(workerId) {
+            return request('/distributed/serverless/test', {
                 method: 'POST',
-                body: JSON.stringify({ worker_id: workerId, ...data })
+                body: JSON.stringify({ worker_id: workerId }),
+            }, { retry: false });
+        },
+
+        async getServerlessStatus(workerId) {
+            return request(`/distributed/serverless/status/${encodeURIComponent(workerId)}`);
+        },
+
+        async cancelServerlessWorker(workerId) {
+            return request('/distributed/serverless/cancel', {
+                method: 'POST',
+                body: JSON.stringify({ worker_id: workerId }),
             }, { retry: false });
         },
         

web/constants.js

@@ -104,7 +104,8 @@ export const PULSE_ANIMATION_CSS = `
         transition: max-height 0.3s ease, opacity 0.3s ease, padding 0.3s ease, margin 0.3s ease;
     }
     .worker-settings.expanded {
-        max-height: 500px;
+        /* Let long forms and wrapped labels fit; the sidebar owns scrolling. */
+        max-height: none;
         opacity: 1;
         padding: 12px;
         margin-top: 8px;
@@ -130,7 +131,7 @@ export const PULSE_ANIMATION_CSS = `
 `;
 
 export const UI_STYLES = {
-    statusDot: "display: inline-block; width: 10px; height: 10px; border-radius: 50%; margin-right: 10px;",
+    statusDot: "display: inline-block; flex: 0 0 10px; width: 10px; height: 10px; border-radius: 50%; margin-right: 10px;",
     controlsDiv: "padding: 0 12px 12px 12px; display: flex; gap: 6px;",
     formGroup: "display: flex; flex-direction: column; gap: 5px;",
     formLabel: "font-size: 12px; color: var(--dist-label-text, #ccc); font-weight: 500;",
@@ -146,12 +147,12 @@ export const UI_STYLES = {
     // Column styles
     columnBase: "display: flex; align-items: center; justify-content: center;",
     checkboxColumn: "flex: 0 0 44px; display: flex; align-items: center; justify-content: center; cursor: default;",
-    contentColumn: "flex: 1; display: flex; flex-direction: column; transition: background-color 0.2s ease;",
+    contentColumn: "flex: 1; min-width: 0; display: flex; flex-direction: column; transition: background-color 0.2s ease;",
     iconColumn: "width: 44px; flex-shrink: 0; font-size: 20px; color: var(--dist-placeholder-add-color, #666);",
     
     // Row and content styles
     infoRow: "display: flex; align-items: center; padding: 12px; cursor: pointer; min-height: 64px;",
-    workerContent: "display: flex; align-items: center; gap: 10px; flex: 1;",
+    workerContent: "display: flex; align-items: center; gap: 10px; flex: 1; min-width: 0;",
     
     // Form and controls styles
     buttonGroup: "display: flex; gap: 4px; margin-top: 10px;",

web/distributed.css

@@ -235,6 +235,17 @@
     border-radius: 4px;
 }
 
+.dist-worker-info {
+    min-width: 0;
+    overflow-wrap: anywhere;
+}
+
+.dist-serverless-status {
+    display: block;
+    margin-top: 4px;
+    line-height: 1.4;
+}
+
 .dist-worker-info__title {
     color: var(--dist-card-title) !important;
     font-size: 1.03em;

web/distributedValue.js

@@ -2,7 +2,6 @@ import { app } from "/scripts/app.js";
 import { ENDPOINTS } from "./constants.js";
 
 const NODE_CLASS = "DistributedValue";
-const CONVERTED_WIDGET = "converted-widget";
 const DYNAMIC_DEFAULT_WIDGET = "_dv_default";
 const DYNAMIC_WORKER_WIDGET_PREFIX = "_dv_worker_";
 const WORKERS_CHANGED_EVENT = "distributed:workers-changed";
@@ -42,15 +41,13 @@ function getDynamicWorkerWidgets(node) {
     return (node.widgets || []).filter((w) => w.name.startsWith(DYNAMIC_WORKER_WIDGET_PREFIX));
 }
 
-function hideWidgetForGood(node, widget, suffix = "") {
+function hideWidgetForGood(widget) {
     if (!widget) return;
-    if (typeof widget.type === "string" && widget.type.startsWith(CONVERTED_WIDGET)) return;
-
-    widget.origType = widget.type;
-    widget.origComputeSize = widget.computeSize;
-    widget.origSerializeValue = widget.serializeValue;
-    widget.computeSize = () => [0, -4];
-    widget.type = `${CONVERTED_WIDGET}${suffix}`;
+    // These are serialized backing fields, not widgets converted into sockets.
+    // Keep their native type/serializer and mutate the shared options in place
+    // so both the classic canvas and Nodes 2.0 suppress the whole widget row.
+    widget.options ??= {};
+    widget.options.hidden = true;
 
     // Hide any attached DOM element (multiline widgets).
     if (widget.element) widget.element.style.display = "none";
@@ -58,14 +55,14 @@ function hideWidgetForGood(node, widget, suffix = "") {
 
     if (widget.linkedWidgets) {
         for (const linked of widget.linkedWidgets) {
-            hideWidgetForGood(node, linked, `:${widget.name}`);
+            hideWidgetForGood(linked);
         }
     }
 }
 
 function hideRawWidgets(node) {
-    hideWidgetForGood(node, getRawDefaultWidget(node), ":default_value");
-    hideWidgetForGood(node, getRawWorkerValuesWidget(node), ":worker_values");
+    hideWidgetForGood(getRawDefaultWidget(node));
+    hideWidgetForGood(getRawWorkerValuesWidget(node));
 }
 
 function removeDynamicDefaultWidget(node) {

web/executionUtils.js

@@ -112,6 +112,21 @@ export async function performPreflightCheck(extension, workers) {
     const startTime = Date.now();
     
     const checkPromises = workers.map(async (worker) => {
+        if (worker.type === "serverless") {
+            try {
+                const providerStatus = await extension.api.getServerlessStatus(worker.id);
+                if (providerStatus?.ok) {
+                    extension.log(`Serverless worker ${worker.name} is ready to scale`, "debug");
+                    return { worker, active: true };
+                }
+                extension.log(`Serverless worker ${worker.name} is not ready: ${providerStatus?.message || "unavailable"}`, "debug");
+                return { worker, active: false };
+            } catch (error) {
+                extension.log(`Serverless worker ${worker.name} status check failed: ${error.message}`, "debug");
+                return { worker, active: false };
+            }
+        }
+
         const workerUrl = getWorkerUrl(extension, worker);
         
         extension.log(`Pre-flight checking ${worker.name} at: ${workerUrl}`, "debug");

web/main.js

@@ -15,7 +15,8 @@ import { parseHostInput, getMasterUrl as buildMasterUrl } from './urlUtils.js';
 
 const WORKERS_CHANGED_EVENT = "distributed:workers-changed";
 
-class DistributedExtension {
+// Exported for tests; ComfyUI only uses the registerExtension side effect below.
+export class DistributedExtension {
     constructor() {
         this.config = null;
         this.originalQueuePrompt = api.queuePrompt.bind(api);
@@ -196,6 +197,7 @@ class DistributedExtension {
 
     async updateWorkerEnabled(workerId, enabled) {
         const worker = this.config.workers.find(w => w.id === workerId);
+        const previousEnabled = worker ? Boolean(worker.enabled) : !enabled;
         if (worker) {
             worker.enabled = enabled;
             this.state.updateWorker(workerId, { enabled });
@@ -219,6 +221,19 @@ class DistributedExtension {
             await this.api.updateWorker(workerId, { enabled });
         } catch (error) {
             this.log("Error updating worker: " + error.message, "error");
+            // The backend kept the old state (e.g. a serverless worker without a
+            // saved API key); show that instead of a toggle that did not stick.
+            if (worker) {
+                worker.enabled = previousEnabled;
+                this.state.updateWorker(workerId, { enabled: previousEnabled });
+                this._emitWorkersChanged();
+            }
+            this.app?.extensionManager?.toast?.add({
+                severity: "error",
+                summary: enabled ? "Could not enable worker" : "Could not disable worker",
+                detail: error.message,
+                life: 5000,
+            });
         }
 
         if (this.panelElement) {

web/masterDetection.js

@@ -42,6 +42,15 @@ export async function detectMasterIP(extension) {
             if (shouldAutoPopulate) {
                 extension.log(`Auto-populating workers based on ${extension.cudaDeviceCount} CUDA devices (excluding master on CUDA ${extension.masterCudaDevice})`, "info");
 
+                const workerCount = extension.cudaDeviceCount - (
+                    Number.isInteger(extension.masterCudaDevice) &&
+                    extension.masterCudaDevice >= 0 &&
+                    extension.masterCudaDevice < extension.cudaDeviceCount ? 1 : 0
+                );
+                const workerPorts = data.local_worker_ports;
+                if (!Array.isArray(workerPorts) || workerPorts.length !== workerCount) {
+                    throw new Error("Could not allocate enough available local worker ports; check the server log");
+                }
                 const newWorkers = [];
                 let workerNum = 1;
                 let portOffset = 0;
@@ -56,7 +65,7 @@ export async function detectMasterIP(extension) {
                         id: generateUUID(),
                         name: `Worker ${workerNum}`,
                         host: isRunpod ? null : "localhost",
-                        port: 8189 + portOffset,
+                        port: workerPorts[portOffset],
                         cuda_device: i,
                         enabled: true,
                         extra_args: isRunpod ? "--listen" : "",

web/sidebarRenderer.js

@@ -18,6 +18,19 @@ export function updateWorkerCard(extension, workerId, newStatus = {}) {
     const workerState = extension.state.getWorker(workerId);
     const isLaunching = Boolean(workerState?.launching);
 
+    if (worker.type === "serverless") {
+        const providerStatus = workerState?.serverlessStatus || {};
+        if (newStatus.online && newStatus.processing) {
+            extension.ui.updateStatusDot(workerId, STATUS_COLORS.PROCESSING_YELLOW, `Runpod active (${newStatus.queueCount || 0} queued)`, false);
+        } else if (newStatus.online) {
+            extension.ui.updateStatusDot(workerId, STATUS_COLORS.ONLINE_GREEN, providerStatus.message || "Runpod ready to scale", false);
+        } else if (worker.enabled) {
+            extension.ui.updateStatusDot(workerId, STATUS_COLORS.OFFLINE_RED, providerStatus.message || "Runpod endpoint unavailable", false);
+        }
+        updateWorkerControls(extension, workerId);
+        return true;
+    }
+
     if (isLaunching && !newStatus.online) {
         extension.ui.updateStatusDot(workerId, STATUS_COLORS.PROCESSING_YELLOW, "Launching...", true);
     } else if (newStatus.online && newStatus.processing) {

web/tests/distributedValue.test.js

@@ -0,0 +1,120 @@
+import { readFileSync } from "node:fs";
+import vm from "node:vm";
+import { describe, expect, it, vi } from "vitest";
+
+// Evaluate this repository's browser entrypoint without needing a ComfyUI server.
+// The real-renderer acceptance additionally checks the input rows in Chromium.
+const source = readFileSync(new URL("../distributedValue.js", import.meta.url), "utf8")
+    .replace(/^import .*;\r?\n/gm, "");
+
+function setup({ connected = false, targetType = "STRING" } = {}) {
+    let extension;
+    const listeners = new Map();
+    const tasks = [];
+    const workers = [
+        { id: "gpu-a", name: "GPU A", enabled: true },
+        { id: "gpu-b", name: "GPU B", enabled: true },
+        { id: "off", name: "Disabled", enabled: false },
+    ];
+    const target = {
+        inputs: [{ name: "value" }],
+        widgets: [{ name: "value", type: targetType === "INT" ? "number" : "string", options: { step: 1, precision: 0 } }],
+    };
+    const graph = { links: { 1: { target_id: 2, target_slot: 0 } }, getNodeById: () => target };
+    const raw = ["default_value", "worker_values"].map((name, index) => ({
+        name,
+        type: "text",
+        value: index === 0 ? "saved default" : '{"1":"saved worker"}',
+        options: { multiline: false },
+        computeSize: vi.fn(() => [200, 20]),
+        serializeValue: vi.fn(function () { return this.value; }),
+    }));
+    const node = {
+        comfyClass: "DistributedValue", graph, widgets: [...raw], size: [200, 100],
+        inputs: raw.map(w => ({ name: w.name, widget: { name: w.name }, link: null })),
+        outputs: [{ links: connected ? [1] : [] }],
+        computeSize: () => [200, 100], setSize: vi.fn(), setDirtyCanvas: vi.fn(),
+        addWidget(type, name, value, callback, options) {
+            const widget = { type, name, value, callback, options };
+            this.widgets.push(widget);
+            return widget;
+        },
+        configure(data) {
+            data.widgets_values.forEach((value, i) => { this.widgets[i].value = value; });
+            return "configured";
+        },
+    };
+    vm.runInNewContext(source, {
+        app: { graph, registerExtension: ext => { extension = ext; } },
+        ENDPOINTS: { CONFIG: "/distributed/config" },
+        fetch: async () => ({ ok: true, json: async () => ({ workers }) }),
+        window: { addEventListener: (name, handler) => listeners.set(name, handler) },
+        setTimeout: callback => { tasks.push(callback); }, console,
+    }, { filename: "distributedValue.js" });
+    return { node, raw, extension, listeners, tasks, flush: () => { while (tasks.length) tasks.shift()(); } };
+}
+
+describe("Distributed Value internal widget visibility", () => {
+    it("hides raw fields natively without converting their types or replacing their options", async () => {
+        const h = setup();
+        const options = h.raw.map(w => w.options);
+        const sizes = h.raw.map(w => w.computeSize);
+        const serializers = h.raw.map(w => w.serializeValue);
+        const slots = h.node.inputs;
+        await h.extension.nodeCreated(h.node);
+
+        for (const [i, widget] of h.raw.entries()) {
+            expect(widget.type).toBe("text");
+            expect(widget.options).toBe(options[i]);
+            expect(widget.options.hidden).toBe(true);
+            expect(widget.computeSize).toBe(sizes[i]);
+            expect(widget.serializeValue).toBe(serializers[i]);
+            expect(h.node.widgets[i]).toBe(widget);
+        }
+        expect(h.node.inputs).toBe(slots);
+        expect(h.node.widgets.slice(2).map(w => w.label)).toEqual(["default_value", "GPU A", "GPU B"]);
+        expect(h.node.widgets.slice(2).every(w => !w.options.hidden)).toBe(true);
+    });
+
+    it("keeps typed edits in the original serialized fields across rebuild/configure", async () => {
+        const h = setup({ connected: true, targetType: "INT" });
+        await h.extension.nodeCreated(h.node);
+        h.node.widgets.find(w => w.name === "_dv_default").callback(42);
+        h.node.widgets.find(w => w.name === "_dv_worker_1").callback(7);
+        h.node.widgets.find(w => w.name === "_dv_worker_2").callback(9);
+        const values = h.raw.map(w => w.serializeValue());
+        expect(values[0]).toBe(42);
+        expect(JSON.parse(values[1])).toMatchObject({
+            _type: "INT", 1: "7", 2: "9", _by_worker_id: { "gpu-a": "7", "gpu-b": "9" },
+        });
+        expect(h.node.configure({ widgets_values: values })).toBe("configured");
+        h.flush();
+        expect(h.raw.map(w => w.serializeValue())).toEqual(values);
+        expect(h.raw.every(w => w.options.hidden && w.type === "text")).toBe(true);
+        expect(h.node.widgets.slice(2).map(w => w.value)).toEqual([42, 7, 9]);
+    });
+
+    it("reapplies visibility on worker refresh without duplicating raw or dynamic fields", async () => {
+        const h = setup();
+        await h.extension.nodeCreated(h.node);
+        h.raw[0].options.hidden = false;
+        await h.listeners.get("distributed:workers-changed")({ detail: { workers: [
+            { id: "gpu-b", name: "Renamed B", enabled: true },
+        ] } });
+        expect(h.raw.every(w => w.options.hidden)).toBe(true);
+        expect(h.node.widgets.map(w => w.name)).toEqual(["default_value", "worker_values", "_dv_default", "_dv_worker_1"]);
+        expect(h.node.widgets[3].label).toBe("Renamed B");
+    });
+
+    it("hides linked backing widgets and handles absent options without altering serializers", async () => {
+        const h = setup();
+        delete h.raw[1].options;
+        const linked = { type: "text", options: {}, serializeValue: vi.fn(() => "linked") };
+        h.raw[0].linkedWidgets = [linked];
+        await h.extension.nodeCreated(h.node);
+        expect(h.raw[1].options.hidden).toBe(true);
+        expect(linked.options.hidden).toBe(true);
+        expect(linked.type).toBe("text");
+        expect(linked.serializeValue()).toBe("linked");
+    });
+});

web/tests/executionUtils.test.js

@@ -1,15 +0,0 @@
-import { describe, expect, it } from "vitest";
-
-import { buildWorkerWebSocketUrl } from "../urlUtils.js";
-
-
-describe("execution decision helpers", () => {
-    it("buildWorkerWebSocketUrl converts http/https to ws/wss", () => {
-        expect(buildWorkerWebSocketUrl("http://worker.local:8188")).toBe(
-            "ws://worker.local:8188/distributed/worker_ws"
-        );
-        expect(buildWorkerWebSocketUrl("https://worker.example.com")).toBe(
-            "wss://worker.example.com/distributed/worker_ws"
-        );
-    });
-});

web/tests/masterDetection.test.js

@@ -0,0 +1,65 @@
+import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
+import { detectMasterIP } from "../masterDetection.js";
+
+describe("automatic local worker ports", () => {
+    let originalWindow;
+    beforeEach(() => {
+        originalWindow = globalThis.window;
+        globalThis.window = { location: { hostname: "localhost", port: "443" } };
+    });
+    afterEach(() => { globalThis.window = originalWindow; });
+
+    function makeExtension(overrides = {}) {
+        return {
+            config: { workers: [], settings: {}, master: {} },
+            log: vi.fn(),
+            api: {
+                getNetworkInfo: vi.fn().mockResolvedValue({
+                    cuda_device: 0, cuda_device_count: 3,
+                    master_port: 8189, local_worker_ports: [8191, 8193],
+                    ...overrides,
+                }),
+                updateMaster: vi.fn().mockResolvedValue({}),
+                updateWorker: vi.fn().mockResolvedValue({}),
+                updateSetting: vi.fn().mockResolvedValue({}),
+            },
+            ui: { updateMasterDisplay: vi.fn() },
+            app: {},
+            loadConfig: vi.fn().mockResolvedValue(),
+        };
+    }
+
+    it("uses server-allocated ports, not hardcoded ports or the browser proxy port", async () => {
+        const extension = makeExtension();
+        await detectMasterIP(extension);
+        expect(extension.config.workers.map(worker => worker.port)).toEqual([8191, 8193]);
+        expect(extension.config.workers.map(worker => worker.cuda_device)).toEqual([1, 2]);
+        expect(extension.api.updateWorker).toHaveBeenCalledTimes(2);
+    });
+
+    it("does not overwrite an existing manually configured worker", async () => {
+        const extension = makeExtension();
+        const worker = { id: "manual", host: "localhost", port: 8189 };
+        extension.config.workers = [worker];
+        await detectMasterIP(extension);
+        expect(extension.config.workers).toEqual([worker]);
+        expect(extension.api.updateWorker).not.toHaveBeenCalled();
+    });
+
+    it("fails without partially saving workers if not enough ports are available", async () => {
+        const extension = makeExtension({ local_worker_ports: [8191] });
+        await detectMasterIP(extension);
+        expect(extension.config.workers).toEqual([]);
+        expect(extension.api.updateWorker).not.toHaveBeenCalled();
+        expect(extension.api.updateSetting).not.toHaveBeenCalled();
+        expect(extension.log).toHaveBeenCalledWith(expect.stringContaining("port"), "error");
+    });
+
+    it("preserves Runpod worker host and launch settings", async () => {
+        globalThis.window.location.hostname = "pod-8189.proxy.runpod.net";
+        const extension = makeExtension();
+        await detectMasterIP(extension);
+        expect(extension.config.workers.map(worker => worker.port)).toEqual([8191, 8193]);
+        expect(extension.config.workers.every(worker => worker.host === null && worker.extra_args === "--listen")).toBe(true);
+    });
+});

web/tests/serverlessWorkers.test.js

@@ -0,0 +1,622 @@
+import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
+
+vi.mock("../../scripts/api.js", () => ({ api: { clientId: "test-client" } }), { virtual: true });
+
+import { createApiClient } from "../apiClient.js";
+import { createWorkerSettingsForm } from "../ui/settingsForm.js";
+import { DistributedUI } from "../ui.js";
+import { checkWorkerStatus, formatServerlessStatus, getWorkerUrl, launchWorker, stopWorker, viewWorkerLog } from "../workerLifecycle.js";
+import { handleClearMemory, handleInterruptWorkers } from "../workerUtils.js";
+import { isRemoteWorker, normalizeRunpodEndpointId, saveWorkerSettings, testServerlessWorker } from "../workerSettings.js";
+import { performPreflightCheck } from "../executionUtils.js";
+
+function createDocumentMock() {
+    const elements = new Map();
+    const makeElement = (tagName) => {
+        const element = {
+            tagName,
+            children: [],
+            dataset: {},
+            style: {},
+            setAttribute(name, value) { this[name] = value; },
+            classList: {
+                values: new Set(),
+                add(...names) { names.forEach((name) => this.values.add(name)); },
+                remove(...names) { names.forEach((name) => this.values.delete(name)); },
+                toggle(name, force) {
+                    const enabled = force ?? !this.values.has(name);
+                    if (enabled) this.values.add(name);
+                    else this.values.delete(name);
+                    return enabled;
+                },
+            },
+            appendChild(child) { this.children.push(child); child.parentNode = this; return child; },
+            dispatchEvent() { this.onchange?.({ target: this }); },
+        };
+        Object.defineProperty(element, "id", {
+            get() { return this._id || ""; },
+            set(value) { this._id = value; elements.set(value, this); },
+        });
+        return element;
+    };
+    return {
+        elements,
+        document: {
+            createElement: makeElement,
+            getElementById: (id) => elements.get(id) || null,
+        },
+    };
+}
+
+function createFormUi() {
+    return {
+        createFormGroup(label, value, id, type = "text", placeholder = "") {
+            const group = document.createElement("div");
+            const input = document.createElement("input");
+            input.id = id;
+            input.value = String(value ?? "");
+            input.type = type;
+            input.placeholder = placeholder;
+            group.appendChild(input);
+            return { group, input, label };
+        },
+        createButton(text, onclick) {
+            const button = document.createElement("button");
+            button.textContent = text;
+            button.onclick = onclick;
+            return button;
+        },
+        createButtonGroup(buttons) {
+            const group = document.createElement("div");
+            buttons.forEach((button) => group.appendChild(button));
+            return group;
+        },
+    };
+}
+
+function makeSaveExtension(worker, updateWorker = vi.fn().mockResolvedValue({})) {
+    return {
+        config: { workers: [worker] },
+        api: { updateWorker },
+        state: { updateWorker: vi.fn(), setWorkerExpanded: vi.fn() },
+        app: { extensionManager: { toast: { add: vi.fn() } } },
+        panelElement: null,
+    };
+}
+
+describe("Runpod serverless worker panel", () => {
+    let originalDocument;
+    let originalWindow;
+    let elements;
+
+    beforeEach(() => {
+        originalDocument = globalThis.document;
+        originalWindow = globalThis.window;
+        const mock = createDocumentMock();
+        elements = mock.elements;
+        globalThis.document = mock.document;
+        globalThis.window = {
+            location: { hostname: "localhost", protocol: "http:", port: "8188", origin: "http://localhost:8188" },
+        };
+    });
+
+    afterEach(() => {
+        globalThis.document = originalDocument;
+        globalThis.window = originalWindow;
+        vi.restoreAllMocks();
+    });
+
+    it("classifies Runpod serverless as remote for worker allocation", () => {
+        expect(isRemoteWorker({}, { type: "serverless" })).toBe(true);
+    });
+
+    it("initializes a saved serverless form before it is attached to the document", () => {
+        // Real document lookups cannot see a form while its card is being built.
+        vi.spyOn(document, "getElementById").mockReturnValue(null);
+        const worker = {
+            id: "saved", name: "Runpod", type: "serverless", endpoint_id: "ep_123",
+            jobs_per_run: 2, concurrency: 1, timeout_seconds: 900, api_key_configured: true,
+        };
+        const form = createWorkerSettingsForm(createFormUi(), {}, worker);
+
+        expect(form.parentNode).toBeUndefined();
+        expect(elements.get("worker-type-saved").value).toBe("serverless");
+        for (const field of ["host", "port", "cuda", "args"]) {
+            expect(elements.get(`${field}-group-saved`).style.display).toBe("none");
+        }
+        expect(elements.get("runpod-text-saved").style.display).toBe("none");
+        for (const field of ["endpoint-id", "api-key", "clear-api-key", "jobs-per-run", "timeout-seconds", "serverless-test"]) {
+            expect(elements.get(`${field}-group-saved`).style.display).toBe("flex");
+        }
+        // The separate concurrency setting was removed; a legacy value is ignored.
+        expect(elements.has("concurrency-saved")).toBe(false);
+        expect(elements.has("concurrency-group-saved")).toBe(false);
+        expect(elements.get("endpoint-id-saved").value).toBe("ep_123");
+        expect(elements.get("jobs-per-run-saved").value).toBe("2");
+        expect(elements.get("timeout-seconds-saved").value).toBe("900");
+        expect(elements.get("api-key-saved").value).toBe("");
+        expect(elements.get("api-key-saved").placeholder).toMatch(/leave blank/i);
+    });
+
+    it("preserves a saved cloud port on first render and applies defaults only on type changes", () => {
+        vi.spyOn(document, "getElementById").mockReturnValue(null);
+        createWorkerSettingsForm(createFormUi(), {}, {
+            id: "cloud", name: "Cloud", type: "cloud", host: "worker.example", port: 8443,
+        });
+        const type = elements.get("worker-type-cloud");
+        expect(type.value).toBe("cloud");
+        expect(elements.get("port-cloud").value).toBe("8443");
+        expect(elements.get("host-cloud").value).toBe("worker.example");
+        expect(elements.get("runpod-text-cloud").style.display).toBe("block");
+
+        type.value = "remote";
+        type.dispatchEvent();
+        type.value = "cloud";
+        type.dispatchEvent();
+        expect(elements.get("port-cloud").value).toBe("443");
+    });
+
+    it("shows only serverless settings and keeps credentials write-only", () => {
+        const worker = {
+            id: "w1", name: "Runpod", type: "remote", host: "worker.example", port: 8188,
+            cuda_device: 0, extra_args: "--test", api_key_configured: true,
+        };
+        const form = createWorkerSettingsForm(createFormUi(), {}, worker);
+        const type = elements.get("worker-type-w1");
+        type.value = "serverless";
+        type.dispatchEvent();
+
+        expect(type.children.map((option) => [option.value, option.textContent])).toContainEqual([
+            "serverless", "Serverless (Runpod)",
+        ]);
+        for (const id of ["host-group-w1", "port-group-w1", "cuda-group-w1", "args-group-w1"]) {
+            expect(elements.get(id).style.display).toBe("none");
+        }
+        for (const id of ["endpoint-id-w1", "api-key-w1", "jobs-per-run-w1", "timeout-seconds-w1"]) {
+            expect(elements.has(id)).toBe(true);
+        }
+        expect(elements.has("concurrency-w1")).toBe(false);
+        for (const id of ["endpoint-id-group-w1", "api-key-group-w1", "clear-api-key-group-w1", "jobs-per-run-group-w1", "timeout-seconds-group-w1", "serverless-test-group-w1"]) {
+            expect(elements.get(id).style.display).toBe("flex");
+        }
+        expect(elements.has("serverless-help-w1")).toBe(false);
+        expect(elements.get("api-key-w1").type).toBe("password");
+        expect(elements.get("api-key-w1").value).toBe("");
+        expect(elements.get("api-key-w1").placeholder).toMatch(/leave blank/i);
+        expect(elements.get("jobs-per-run-w1").value).toBe("1");
+        expect(elements.get("jobs-per-run-w1").min).toBe("1");
+        expect(elements.get("jobs-per-run-w1").max).toBe("16");
+        expect(elements.get("jobs-per-run-w1").title).toBe(
+            "Separate Runpod jobs submitted each run, all at once. Runpod's max workers decides how many GPUs actually run them.",
+        );
+        expect(elements.get("timeout-seconds-w1").value).toBe("1800");
+        expect(elements.get("timeout-seconds-w1").min).toBe("30");
+        expect(elements.get("timeout-seconds-w1").max).toBe("86400");
+        expect(form.children.length).toBeGreaterThan(0);
+    });
+
+    it("disables Clear saved API key while the worker is enabled and explains why", () => {
+        vi.spyOn(document, "getElementById").mockReturnValue(null);
+        const base = { name: "Runpod", type: "serverless", endpoint_id: "ep_123" };
+        createWorkerSettingsForm(createFormUi(), {}, { ...base, id: "on", enabled: true, api_key_configured: true });
+        createWorkerSettingsForm(createFormUi(), {}, { ...base, id: "off", enabled: false, api_key_configured: true });
+        createWorkerSettingsForm(createFormUi(), {}, { ...base, id: "nokey", enabled: false, api_key_configured: false });
+
+        expect(elements.get("clear-api-key-on").disabled).toBe(true);
+        expect(elements.get("clear-api-key-group-on").title).toMatch(/turn this worker off/i);
+        expect(elements.get("clear-api-key-off").disabled).toBe(false);
+        expect(elements.get("clear-api-key-nokey").disabled).toBe(true);
+        expect(elements.get("clear-api-key-group-nokey").title).toMatch(/no api key is saved/i);
+        for (const id of ["on", "off", "nokey"]) {
+            expect(elements.get(`clear-api-key-group-${id}`).title).not.toMatch(/pool/i);
+        }
+    });
+
+    it("saves fixed Runpod settings without enabling or retaining the API key", async () => {
+        const worker = { id: "w2", name: "Old", type: "remote", enabled: false, api_key_configured: false };
+        const extension = makeSaveExtension(worker);
+        elements.set("name-w2", { value: "Runpod worker" });
+        elements.set("worker-type-w2", { value: "serverless" });
+        elements.set("endpoint-id-w2", { value: "ep_123" });
+        elements.set("api-key-w2", { value: "secret-token" });
+        elements.set("clear-api-key-w2", { checked: false });
+        elements.set("jobs-per-run-w2", { value: "4" });
+        elements.set("timeout-seconds-w2", { value: "2400" });
+
+        await saveWorkerSettings(extension, "w2");
+
+        expect(extension.api.updateWorker).toHaveBeenCalledWith("w2", {
+            name: "Runpod worker", type: "serverless", provider: "runpod", endpoint_id: "ep_123",
+            api_key: "secret-token", jobs_per_run: 4, timeout_seconds: 2400, enabled: false,
+        });
+        expect(worker).toMatchObject({ type: "serverless", provider: "runpod", enabled: false, api_key_configured: true });
+        expect(worker).not.toHaveProperty("api_key");
+        expect(JSON.stringify(extension.config)).not.toContain("secret-token");
+        expect(elements.get("api-key-w2").value).toBe("");
+        expect(extension.state.updateWorker).toHaveBeenCalledWith("w2", { enabled: false });
+        expect(JSON.stringify(extension.state.updateWorker.mock.calls)).not.toContain("secret-token");
+    });
+
+    it("labels the single parallelism setting Images per run and drops a legacy concurrency value", async () => {
+        const worker = { id: "legacy", name: "Runpod", type: "serverless", provider: "runpod", enabled: false,
+            api_key_configured: true, jobs_per_run: 1, concurrency: 1 };
+        const extension = makeSaveExtension(worker);
+        elements.set("name-legacy", { value: "Runpod" });
+        elements.set("worker-type-legacy", { value: "serverless" });
+        elements.set("endpoint-id-legacy", { value: "ep_123" });
+        elements.set("api-key-legacy", { value: "" });
+        elements.set("clear-api-key-legacy", { checked: false });
+        elements.set("jobs-per-run-legacy", { value: "2" });
+        elements.set("timeout-seconds-legacy", { value: "1800" });
+
+        await saveWorkerSettings(extension, "legacy");
+
+        const payload = extension.api.updateWorker.mock.calls[0][1];
+        expect(payload.jobs_per_run).toBe(2);
+        expect(payload).not.toHaveProperty("concurrency");
+        expect(worker.jobs_per_run).toBe(2);
+        expect(worker).not.toHaveProperty("concurrency");
+
+        elements.set("jobs-per-run-legacy", { value: "17" });
+        await saveWorkerSettings(extension, "legacy");
+        expect(extension.api.updateWorker).toHaveBeenCalledTimes(1);
+        expect(extension.app.extensionManager.toast.add).toHaveBeenLastCalledWith(
+            expect.objectContaining({ detail: "Images per run must be a whole number from 1 to 16" }),
+        );
+    });
+
+    it("trims a pasted Runpod URL to the endpoint ID and explains other invalid IDs", async () => {
+        expect(normalizeRunpodEndpointId("  abc123xyz ")).toBe("abc123xyz");
+        expect(normalizeRunpodEndpointId("https://api.runpod.ai/v2/abc123xyz/run")).toBe("abc123xyz");
+        expect(normalizeRunpodEndpointId("api.runpod.ai/v2/abc_12-3")).toBe("abc_12-3");
+        expect(normalizeRunpodEndpointId("https://www.runpod.io/console/serverless/user/endpoint/abc")).toBe(
+            "https://www.runpod.io/console/serverless/user/endpoint/abc",
+        );
+
+        const worker = { id: "url", name: "Runpod", type: "serverless", provider: "runpod", enabled: false, api_key_configured: true };
+        const extension = makeSaveExtension(worker);
+        elements.set("name-url", { value: "Runpod" });
+        elements.set("worker-type-url", { value: "serverless" });
+        elements.set("endpoint-id-url", { value: "https://api.runpod.ai/v2/abc123xyz/runsync" });
+        elements.set("api-key-url", { value: "" });
+        elements.set("clear-api-key-url", { checked: false });
+        elements.set("jobs-per-run-url", { value: "1" });
+        elements.set("timeout-seconds-url", { value: "1800" });
+        await saveWorkerSettings(extension, "url");
+        expect(extension.api.updateWorker.mock.calls[0][1].endpoint_id).toBe("abc123xyz");
+
+        elements.set("endpoint-id-url", { value: "https://www.runpod.io/console/serverless/endpoint/abc" });
+        await saveWorkerSettings(extension, "url");
+        expect(extension.api.updateWorker).toHaveBeenCalledTimes(1);
+        expect(extension.app.extensionManager.toast.add).toHaveBeenLastCalledWith(
+            expect.objectContaining({ detail: expect.stringMatching(/just the Runpod endpoint ID/) }),
+        );
+    });
+
+    it("asks before a type change deletes the saved API key, and cancels cleanly", async () => {
+        const worker = { id: "conv", name: "Runpod", type: "serverless", provider: "runpod", enabled: false, api_key_configured: true };
+        const extension = makeSaveExtension(worker);
+        elements.set("name-conv", { value: "Runpod" });
+        elements.set("worker-type-conv", { value: "remote" });
+        elements.set("host-conv", { value: "192.168.1.20" });
+        elements.set("port-conv", { value: "8188" });
+        const confirmSpy = vi.fn().mockReturnValue(false);
+        globalThis.confirm = confirmSpy;
+        try {
+            await saveWorkerSettings(extension, "conv");
+            expect(confirmSpy).toHaveBeenCalledWith(expect.stringMatching(/saved Runpod API key will be deleted/));
+            expect(extension.api.updateWorker).not.toHaveBeenCalled();
+            expect(worker.type).toBe("serverless");
+
+            confirmSpy.mockReturnValue(true);
+            await saveWorkerSettings(extension, "conv");
+            expect(extension.api.updateWorker).toHaveBeenCalledTimes(1);
+            expect(extension.api.updateWorker.mock.calls[0][1].type).toBe("remote");
+        } finally {
+            delete globalThis.confirm;
+        }
+    });
+
+    it("does not ask for confirmation when a serverless worker without a key changes type", async () => {
+        const worker = { id: "nokey2", name: "Runpod", type: "serverless", provider: "runpod", enabled: false, api_key_configured: false };
+        const extension = makeSaveExtension(worker);
+        elements.set("name-nokey2", { value: "Runpod" });
+        elements.set("worker-type-nokey2", { value: "remote" });
+        elements.set("host-nokey2", { value: "192.168.1.20" });
+        elements.set("port-nokey2", { value: "8188" });
+        const confirmSpy = vi.fn().mockReturnValue(false);
+        globalThis.confirm = confirmSpy;
+        try {
+            await saveWorkerSettings(extension, "nokey2");
+            expect(confirmSpy).not.toHaveBeenCalled();
+            expect(extension.api.updateWorker).toHaveBeenCalledTimes(1);
+        } finally {
+            delete globalThis.confirm;
+        }
+    });
+
+    it("omits a blank API key so the saved key is preserved", async () => {
+        const worker = { id: "w-blank", name: "Runpod", type: "serverless", provider: "runpod", enabled: true, api_key_configured: true };
+        const extension = makeSaveExtension(worker);
+        elements.set("name-w-blank", { value: "Runpod" });
+        elements.set("worker-type-w-blank", { value: "serverless" });
+        elements.set("endpoint-id-w-blank", { value: "ep_123" });
+        elements.set("api-key-w-blank", { value: "" });
+        elements.set("clear-api-key-w-blank", { checked: false });
+        elements.set("jobs-per-run-w-blank", { value: "1" });
+        elements.set("timeout-seconds-w-blank", { value: "1800" });
+
+        await saveWorkerSettings(extension, "w-blank");
+
+        const payload = extension.api.updateWorker.mock.calls[0][1];
+        expect(payload).not.toHaveProperty("api_key");
+        expect(payload).not.toHaveProperty("clear_api_key");
+        expect(worker.api_key_configured).toBe(true);
+        expect(worker).not.toHaveProperty("api_key");
+    });
+
+    it("omits a blank key to preserve it and sends an explicit clear flag when requested", async () => {
+        const worker = { id: "w3", name: "Runpod", type: "serverless", provider: "runpod", enabled: true, api_key_configured: true };
+        const extension = makeSaveExtension(worker);
+        elements.set("name-w3", { value: "Runpod" });
+        elements.set("worker-type-w3", { value: "serverless" });
+        elements.set("endpoint-id-w3", { value: "ep_123" });
+        elements.set("api-key-w3", { value: "" });
+        elements.set("clear-api-key-w3", { checked: true });
+        elements.set("jobs-per-run-w3", { value: "1" });
+        elements.set("timeout-seconds-w3", { value: "1800" });
+
+        await saveWorkerSettings(extension, "w3");
+
+        expect(extension.api.updateWorker).toHaveBeenCalledWith("w3", {
+            name: "Runpod", type: "serverless", provider: "runpod", endpoint_id: "ep_123",
+            clear_api_key: true, jobs_per_run: 1, timeout_seconds: 1800, enabled: true,
+        });
+        expect(worker.api_key_configured).toBe(false);
+        expect(worker).not.toHaveProperty("api_key");
+    });
+
+    it.each([
+        [undefined, "Checking status…"],
+        [{ ok: true, queueRemaining: 0, jobs: [] }, "Ready"],
+        [{ ok: true, queueRemaining: 1, jobs: [{ status: "IN_QUEUE" }] }, "Queued"],
+        [{ ok: true, jobs: [{ status: "IN_PROGRESS" }] }, "Running"],
+        [{ ok: true, jobs: [{ status: "RUNNING" }, { status: "IN_QUEUE" }] }, "Running"],
+        [{ ok: true, jobs: [{ status: "RUNNING" }, { status: "IN_PROGRESS" }] }, "Running · 2 jobs"],
+        [{ ok: true, jobs: [{ status: "DOWNLOADING" }] }, "Downloading result"],
+        [{ ok: true, jobs: [{ status: "CANCEL_REQUESTED" }] }, "Cancelling"],
+        [{ ok: true, queueRemaining: 1 }, "Active · 1 job"],
+        [{ ok: true, queueRemaining: 3 }, "Active · 3 jobs"],
+        [{ ok: true, jobs: [{ status: "COMPLETED" }] }, "Ready"],
+        [{ ok: true, jobs: [{ status: "FAILED" }] }, "Last job failed"],
+        [{ ok: false, message: "Check the saved endpoint ID and API key" }, "Unavailable"],
+    ])("formats provider state as one plain-language summary: %j", (status, expected) => {
+        expect(formatServerlessStatus(status)).toBe(expected);
+    });
+
+    it("keeps status above a consistent endpoint info box and retains expanded settings", () => {
+        const ui = new DistributedUI();
+        const worker = {
+            id: "compact", name: "Used Car Inventory", type: "serverless", enabled: true,
+            endpoint_id: "ep_private_id", jobs_per_run: 1, concurrency: 1,
+        };
+        const extension = {
+            config: { workers: [worker] },
+            state: {
+                isWorkerExpanded: () => false,
+                getWorker: () => ({ serverlessStatus: { ok: true, queueRemaining: 1, jobs: [{ status: "IN_QUEUE" }] } }),
+            },
+        };
+        const card = ui.renderEntityCard("worker", worker, extension);
+        const collect = (element) => [element, ...(element.children || []).flatMap(collect)];
+        const info = collect(card).find((element) => element.classList.values.has("dist-worker-info"));
+        expect(info.innerHTML).not.toContain("Runpod Serverless");
+        expect(info.innerHTML).not.toMatch(/ep_private_id|jobs\/run|slots/);
+        expect(elements.get("serverless-status-compact").textContent).toBe("Queued");
+        expect(elements.get("endpoint-id-compact").value).toBe("ep_private_id");
+        expect(Number(elements.get("jobs-per-run-compact").value)).toBe(1);
+        expect(elements.has("concurrency-compact")).toBe(false);
+        const box = elements.get("controls-compact").children[0].children[0];
+        expect(box.textContent).toBe("Runpod Serverless endpoint");
+        expect(box.classList.values.has("dist-info-box")).toBe(true);
+        expect(box.style.cssText).toBe(ui.styles.infoBox);
+        expect(elements.get("status-compact").style.cssText).toContain("flex: 0 0 10px");
+    });
+
+    it("uses provider status instead of a direct ComfyUI URL probe", async () => {
+        const statusElement = { textContent: "" };
+        elements.set("serverless-status-w4", statusElement);
+        const status = {
+            ok: true, queueRemaining: 0, message: "Ready to scale",
+            jobs: [{ job_id: "job-1", status: "RUNNING", worker_id: "w4", execution_id: "exec-1" }],
+        };
+        const extension = {
+            config: { workers: [{ id: "w4", name: "Runpod", type: "serverless", enabled: true }] },
+            api: { getServerlessStatus: vi.fn().mockResolvedValue(status), probeWorker: vi.fn() },
+            statusCheckAbortController: null,
+            state: {
+                setWorkerStatus: vi.fn(),
+                updateWorker: vi.fn(),
+                getWorkerStatus: vi.fn().mockReturnValue({ online: true, processing: false, queueCount: 0 }),
+                getWorker: vi.fn().mockReturnValue({}),
+                isWorkerLaunching: vi.fn().mockReturnValue(false),
+            },
+            updateWorkerCard: vi.fn().mockReturnValue(true),
+            log: vi.fn(),
+        };
+
+        await checkWorkerStatus(extension, extension.config.workers[0]);
+
+        expect(extension.api.getServerlessStatus).toHaveBeenCalledWith("w4");
+        expect(extension.api.probeWorker).not.toHaveBeenCalled();
+        expect(extension.state.setWorkerStatus).toHaveBeenCalledWith("w4", {
+            online: true, processing: true, queueCount: 0,
+        });
+        expect(statusElement.textContent).toBe("Running");
+        expect(statusElement.title).toBe("Ready to scale");
+    });
+
+    it("considers a healthy zero-worker Runpod pool ready and never builds a worker URL", async () => {
+        const worker = { id: "w-ready", name: "Runpod", type: "serverless", enabled: true };
+        const extension = {
+            api: {
+                getServerlessStatus: vi.fn().mockResolvedValue({ ok: true, queueRemaining: 0, message: "Ready to scale" }),
+                probeWorker: vi.fn(),
+            },
+            log: vi.fn(),
+        };
+
+        await expect(performPreflightCheck(extension, [worker])).resolves.toEqual([worker]);
+        expect(extension.api.getServerlessStatus).toHaveBeenCalledWith("w-ready");
+        expect(extension.api.probeWorker).not.toHaveBeenCalled();
+        expect(getWorkerUrl(extension, worker)).toBeNull();
+    });
+
+    it("does not render or invoke direct ComfyUI launch, stop, or log controls", async () => {
+        const ui = new DistributedUI();
+        const worker = { id: "w-controls", name: "Runpod", type: "serverless", enabled: true };
+        const controls = ui.createControlsSection({ dynamic: true }, worker, {}, true);
+
+        const extension = {
+            config: { workers: [worker] },
+            api: {
+                launchWorker: vi.fn(), stopWorker: vi.fn(), getRemoteWorkerLog: vi.fn(),
+            },
+        };
+
+        const box = controls.children[0].children[0];
+        expect(box.textContent).toBe("Runpod Serverless endpoint");
+        expect(box.tagName).toBe("div");
+        expect(controls.children[0].children).toHaveLength(1);
+        await launchWorker(extension, worker.id);
+        await stopWorker(extension, worker.id);
+        await viewWorkerLog(extension, worker.id, true);
+        expect(extension.api.launchWorker).not.toHaveBeenCalled();
+        expect(extension.api.stopWorker).not.toHaveBeenCalled();
+        expect(extension.api.getRemoteWorkerLog).not.toHaveBeenCalled();
+    });
+
+    it("uses the serverless status, test, and cancel routes with the frozen request shapes", async () => {
+        const originalFetch = globalThis.fetch;
+        const statusPayload = {
+            ok: true,
+            queueRemaining: 0,
+            message: "Ready to scale",
+            jobs: [{ job_id: "job-1", status: "RUNNING", worker_id: "w5", execution_id: "exec-1" }],
+        };
+        globalThis.fetch = vi.fn()
+            .mockResolvedValueOnce({ ok: true, status: 200, json: vi.fn().mockResolvedValue({ ok: true, message: "Endpoint test passed" }) })
+            .mockResolvedValueOnce({ ok: true, status: 200, json: vi.fn().mockResolvedValue(statusPayload) })
+            .mockResolvedValueOnce({ ok: true, status: 200, json: vi.fn().mockResolvedValue({ ok: true }) });
+        try {
+            const client = createApiClient("http://localhost:8188");
+            await client.testServerlessWorker("w5");
+            await expect(client.getServerlessStatus("w5")).resolves.toEqual(statusPayload);
+            await client.cancelServerlessWorker("w5");
+
+            expect(globalThis.fetch).toHaveBeenNthCalledWith(1, "http://localhost:8188/distributed/serverless/test", expect.objectContaining({
+                method: "POST", body: JSON.stringify({ worker_id: "w5" }),
+            }));
+            expect(globalThis.fetch).toHaveBeenNthCalledWith(2, "http://localhost:8188/distributed/serverless/status/w5", expect.any(Object));
+            expect(globalThis.fetch).toHaveBeenNthCalledWith(3, "http://localhost:8188/distributed/serverless/cancel", expect.objectContaining({
+                method: "POST", body: JSON.stringify({ worker_id: "w5" }),
+            }));
+        } finally {
+            globalThis.fetch = originalFetch;
+        }
+    });
+
+    it("tests only the saved Runpod endpoint and reports the backend message", async () => {
+        const button = document.createElement("button");
+        button.id = "test-serverless-w6";
+        button.textContent = "Test Saved Endpoint";
+        const extension = {
+            api: {
+                testServerlessWorker: vi.fn().mockResolvedValue({ ok: true, message: "Endpoint reachable" }),
+                queueDistributed: vi.fn(),
+            },
+            app: { extensionManager: { toast: { add: vi.fn() } } },
+        };
+
+        await expect(testServerlessWorker(extension, "w6")).resolves.toEqual({ ok: true, message: "Endpoint reachable" });
+
+        expect(extension.api.testServerlessWorker).toHaveBeenCalledWith("w6");
+        expect(extension.api.queueDistributed).not.toHaveBeenCalled();
+        expect(extension.app.extensionManager.toast.add).toHaveBeenCalledWith(expect.objectContaining({
+            severity: "success", detail: "Endpoint reachable",
+        }));
+        expect(button.textContent).toBe("Test Saved Endpoint");
+        expect(button.disabled).toBe(false);
+    });
+
+    it("redacts API-key-bearing worker update errors from logs and user-visible exceptions", async () => {
+        const originalFetch = globalThis.fetch;
+        const logSpy = vi.spyOn(console, "log").mockImplementation(() => {});
+        const secret = "never-log-this-runpod-key";
+        globalThis.fetch = vi.fn().mockResolvedValue({
+            ok: false,
+            status: 400,
+            json: vi.fn().mockResolvedValue({ message: `Rejected key ${secret}` }),
+        });
+        try {
+            const client = createApiClient("http://localhost:8188");
+            await expect(client.updateWorker("w-secret", { api_key: secret })).rejects.toThrow("[redacted]");
+            expect(logSpy.mock.calls.flat().join(" ")).not.toContain(secret);
+        } finally {
+            globalThis.fetch = originalFetch;
+        }
+    });
+
+    it("never sends VRAM operations to serverless workers", async () => {
+        const originalFetch = globalThis.fetch;
+        globalThis.fetch = vi.fn();
+        vi.useFakeTimers();
+        const button = {
+            textContent: "Clear Worker VRAM", style: { cssText: "" }, disabled: false,
+            classList: { names: new Set(), add(...names) { names.forEach((name) => this.names.add(name)); }, remove(...names) { names.forEach((name) => this.names.delete(name)); } },
+        };
+        const extension = { enabledWorkers: [{ id: "s-vram", name: "Runpod", type: "serverless", enabled: true }] };
+        try {
+            await handleClearMemory(extension, button);
+            expect(globalThis.fetch).not.toHaveBeenCalled();
+        } finally {
+            vi.runOnlyPendingTimers();
+            vi.useRealTimers();
+            globalThis.fetch = originalFetch;
+        }
+    });
+
+    it("cancels each enabled serverless worker once without changing normal worker interrupts", async () => {
+        const originalFetch = globalThis.fetch;
+        globalThis.fetch = vi.fn().mockResolvedValue({ ok: true });
+        vi.useFakeTimers();
+        const button = {
+            textContent: "Interrupt Workers", style: { cssText: "" }, disabled: false,
+            classList: { names: new Set(), add(...names) { names.forEach((name) => this.names.add(name)); }, remove(...names) { names.forEach((name) => this.names.delete(name)); } },
+        };
+        const workers = [
+            { id: "s1", name: "Serverless 1", type: "serverless", enabled: true },
+            { id: "s2", name: "Serverless 2", type: "serverless", enabled: true },
+            { id: "s3", name: "Disabled", type: "serverless", enabled: false },
+            { id: "local", name: "Local", type: "local", enabled: true, port: 8189 },
+        ];
+        const extension = {
+            enabledWorkers: workers.filter((worker) => worker.enabled),
+            api: { cancelServerlessWorker: vi.fn().mockResolvedValue({ ok: true }) },
+            log: vi.fn(),
+        };
+        try {
+            await handleInterruptWorkers(extension, button);
+
+            expect(extension.api.cancelServerlessWorker).toHaveBeenCalledTimes(2);
+            expect(extension.api.cancelServerlessWorker).toHaveBeenNthCalledWith(1, "s1");
+            expect(extension.api.cancelServerlessWorker).toHaveBeenNthCalledWith(2, "s2");
+            expect(globalThis.fetch).toHaveBeenCalledTimes(1);
+            expect(globalThis.fetch.mock.calls[0][0]).toBe("http://localhost:8189/interrupt");
+        } finally {
+            vi.runOnlyPendingTimers();
+            vi.useRealTimers();
+            globalThis.fetch = originalFetch;
+        }
+    });
+});

web/tests/urlUtils.test.js

@@ -106,11 +106,6 @@ describe("buildWorkerWebSocketUrl", () => {
             "wss://worker.example.com/distributed/worker_ws"
         );
     });
-
-    it("always appends /distributed/worker_ws", () => {
-        const url = buildWorkerWebSocketUrl("http://worker.local:8188");
-        expect(url.endsWith("/distributed/worker_ws")).toBe(true);
-    });
 });
 
 

web/tests/workerLifecycle.test.js

@@ -3,7 +3,7 @@ import { afterEach, beforeEach, describe, expect, it } from "vitest";
 import { getWorkerUrl } from "../workerLifecycle.js";
 
 
-describe("workerLifecycle URL construction", () => {
+describe("workerLifecycle URL wiring", () => {
     let originalWindow;
 
     beforeEach(() => {
@@ -22,31 +22,9 @@ describe("workerLifecycle URL construction", () => {
         globalThis.window = originalWindow;
     });
 
-    it("builds local worker URL with explicit local port", () => {
+    // URL variants are covered in urlUtils.test.js; keep the wrapper wiring here.
+    it("forwards the worker and endpoint using window.location", () => {
         const worker = { id: "w1", port: 8189, type: "local" };
         expect(getWorkerUrl({}, worker, "/prompt")).toBe("http://127.0.0.1:8189/prompt");
     });
-
-    it("builds remote worker URL with host:port", () => {
-        const worker = { id: "w2", host: "worker.example.com", port: 9000, type: "remote" };
-        expect(getWorkerUrl({}, worker, "/prompt")).toBe("http://worker.example.com:9000/prompt");
-    });
-
-    it("builds cloud worker URL as https", () => {
-        const worker = { id: "w3", host: "cloud.example.com", port: 443, type: "cloud" };
-        expect(getWorkerUrl({}, worker, "/prompt")).toBe("https://cloud.example.com/prompt");
-    });
-
-    it("rewrites runpod proxy hostname for local worker ports", () => {
-        globalThis.window = {
-            location: {
-                hostname: "podabc.proxy.runpod.net",
-                protocol: "https:",
-                port: "",
-                origin: "https://podabc.proxy.runpod.net",
-            },
-        };
-        const worker = { id: "w4", port: 8189, type: "local" };
-        expect(getWorkerUrl({}, worker, "/prompt")).toBe("https://podabc-8189.proxy.runpod.net/prompt");
-    });
 });

web/tests/workerSettingsLayout.test.js

@@ -0,0 +1,16 @@
+import { describe, expect, it } from "vitest";
+import { PULSE_ANIMATION_CSS } from "../constants.js";
+
+describe("worker settings layout", () => {
+    it("lets expanded forms grow instead of clipping the final controls", () => {
+        const expanded = PULSE_ANIMATION_CSS.match(/\.worker-settings\.expanded\s*\{([^}]+)\}/)?.[1];
+        expect(expanded).toBeDefined();
+        expect(expanded).toMatch(/max-height:\s*none\s*;/);
+    });
+
+    it("still hides collapsed settings", () => {
+        const collapsed = PULSE_ANIMATION_CSS.match(/\.worker-settings\s*\{([^}]+)\}/)?.[1];
+        expect(collapsed).toMatch(/max-height:\s*0\s*;/);
+        expect(collapsed).toMatch(/overflow:\s*hidden\s*;/);
+    });
+});

web/tests/workerToggle.test.js

@@ -0,0 +1,54 @@
+import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
+
+vi.mock("../../scripts/app.js", () => ({ app: { registerExtension: vi.fn() } }), { virtual: true });
+vi.mock("../../scripts/api.js", () => ({ api: { clientId: "test-client", queuePrompt: vi.fn() } }), { virtual: true });
+
+import { DistributedExtension } from "../main.js";
+
+function makeExtension(worker, updateWorker) {
+    return {
+        config: { workers: [worker] },
+        state: { updateWorker: vi.fn() },
+        api: { updateWorker },
+        app: { extensionManager: { toast: { add: vi.fn() } } },
+        ui: { updateStatusDot: vi.fn() },
+        log: vi.fn(),
+        _emitWorkersChanged: vi.fn(),
+        panelElement: null,
+    };
+}
+
+describe("worker enable toggle", () => {
+    let originalDocument;
+    beforeEach(() => {
+        originalDocument = globalThis.document;
+        globalThis.document = { getElementById: () => null };
+    });
+    afterEach(() => {
+        globalThis.document = originalDocument;
+    });
+
+    it("reverts the toggle and explains why when the backend rejects the change", async () => {
+        const worker = { id: "w1", type: "serverless", enabled: false };
+        const extension = makeExtension(worker, vi.fn().mockRejectedValue(new Error("Save an API key before enabling this worker")));
+
+        await DistributedExtension.prototype.updateWorkerEnabled.call(extension, "w1", true);
+
+        expect(worker.enabled).toBe(false);
+        expect(extension.state.updateWorker).toHaveBeenLastCalledWith("w1", { enabled: false });
+        expect(extension.app.extensionManager.toast.add).toHaveBeenCalledWith(expect.objectContaining({
+            severity: "error", summary: "Could not enable worker", detail: "Save an API key before enabling this worker",
+        }));
+    });
+
+    it("keeps the new state when the backend accepts it", async () => {
+        const worker = { id: "w2", type: "serverless", enabled: false };
+        const extension = makeExtension(worker, vi.fn().mockResolvedValue({ status: "success" }));
+
+        await DistributedExtension.prototype.updateWorkerEnabled.call(extension, "w2", true);
+
+        expect(worker.enabled).toBe(true);
+        expect(extension.state.updateWorker).toHaveBeenLastCalledWith("w2", { enabled: true });
+        expect(extension.app.extensionManager.toast.add).not.toHaveBeenCalled();
+    });
+});

web/ui.js

@@ -7,6 +7,14 @@ import { createLogModal } from './ui/logModal.js';
 import { launchWorker, stopWorker, updateWorkerControls, viewWorkerLog } from './workerLifecycle.js';
 import { isRemoteWorker } from './workerSettings.js';
 
+const escapeWorkerInfo = (value) => String(value ?? "").replace(/[&<>"']/g, (character) => ({
+    "&": "&amp;",
+    "<": "&lt;",
+    ">": "&gt;",
+    '"': "&quot;",
+    "'": "&#39;",
+}[character]));
+
 const cardConfigs = {
     master: {
         checkbox: { 
@@ -58,7 +66,12 @@ const cardConfigs = {
         infoText: (data, extension) => {
             const isRemote = isRemoteWorker(extension, data);
             const isCloud = data.type === 'cloud';
-            
+            const isServerless = data.type === 'serverless';
+
+            if (isServerless) {
+                return `<span class="dist-worker-info__title">${escapeWorkerInfo(data.name)}</span>`;
+            }
+
             if (isCloud) {
                 // For cloud workers, don't show port (it's always 443)
                 return `<span class="dist-worker-info__title">${data.name}</span><br><span class="dist-worker-info__meta">${data.host}</span>`;
@@ -590,7 +603,10 @@ export class DistributedUI {
             }
             controlsWrapper.appendChild(badge);
         } else if (config.dynamic && data) {
-            if (isRemote) {
+            if (data.type === 'serverless') {
+                // Match the master/remote footer without exposing direct-worker actions.
+                controlsWrapper.appendChild(this.createInfoBox("Runpod Serverless endpoint"));
+            } else if (isRemote) {
                 const isCloud = data.type === 'cloud';
                 const workerTypeText = isCloud ? "Cloud worker" : "Remote worker";
                 const workerTypeBadge = this.createInfoBox(workerTypeText);

web/ui/entityCard.js

@@ -1,4 +1,4 @@
-import { updateWorkerControls, toggleWorkerExpanded } from "../workerLifecycle.js";
+import { updateWorkerControls, toggleWorkerExpanded, formatServerlessStatus } from "../workerLifecycle.js";
 import { isRemoteWorker } from "../workerSettings.js";
 
 export function renderEntityCard(ui, cardConfigs, entityType, data, extension) {
@@ -74,6 +74,17 @@ export function renderEntityCard(ui, cardConfigs, entityType, data, extension) {
     infoSpan.innerHTML = config.infoText(data, extension);
     workerContent.appendChild(infoSpan);
 
+    if (isWorker && data.type === "serverless") {
+        const statusMessage = document.createElement("small");
+        statusMessage.id = `serverless-status-${data.id}`;
+        statusMessage.className = "dist-worker-info__meta dist-serverless-status";
+        statusMessage.setAttribute("aria-live", "polite");
+        const status = extension.state.getWorker(data.id)?.serverlessStatus;
+        statusMessage.textContent = data.enabled ? formatServerlessStatus(status) : "Disabled";
+        statusMessage.title = status?.message || "";
+        infoSpan.appendChild(statusMessage);
+    }
+
     infoRow.appendChild(workerContent);
 
     let settingsArrow;

web/ui/settingsForm.js

@@ -1,5 +1,8 @@
 import { BUTTON_STYLES } from '../constants.js';
-import { cancelWorkerSettings, deleteWorker, isRemoteWorker, saveWorkerSettings } from '../workerSettings.js';
+import { cancelWorkerSettings, deleteWorker, isRemoteWorker, saveWorkerSettings, testServerlessWorker } from '../workerSettings.js';
+
+export const IMAGES_PER_RUN_TOOLTIP =
+    "Separate Runpod jobs submitted each run, all at once. Runpod's max workers decides how many GPUs actually run them.";
 
 export function createWorkerSettingsForm(ui, extension, worker) {
     const form = document.createElement("div");
@@ -33,9 +36,14 @@ export function createWorkerSettingsForm(ui, extension, worker) {
     cloudOption.value = "cloud";
     cloudOption.textContent = "Cloud";
 
+    const serverlessOption = document.createElement("option");
+    serverlessOption.value = "serverless";
+    serverlessOption.textContent = "Serverless (Runpod)";
+
     typeSelect.appendChild(localOption);
     typeSelect.appendChild(remoteOption);
     typeSelect.appendChild(cloudOption);
+    typeSelect.appendChild(serverlessOption);
 
     const runpodText = document.createElement("a");
     runpodText.id = `runpod-text-${worker.id}`;
@@ -44,50 +52,60 @@ export function createWorkerSettingsForm(ui, extension, worker) {
     runpodText.textContent = "Deploy Cloud Worker with Runpod";
     runpodText.style.cssText = "font-size: 12px; color: #4a90e2; text-decoration: none; margin-top: 4px; display: none; cursor: pointer;";
 
-    const createOnChangeHandler = () => {
-        return (e) => {
-            const workerType = e.target.value;
-            const hostGroup = document.getElementById(`host-group-${worker.id}`);
-            const hostInput = document.getElementById(`host-${worker.id}`);
-            const portGroup = document.getElementById(`port-group-${worker.id}`);
-            const portInput = document.getElementById(`port-${worker.id}`);
-            const cudaGroup = document.getElementById(`cuda-group-${worker.id}`);
-            const argsGroup = document.getElementById(`args-group-${worker.id}`);
-            const runpodTextElem = document.getElementById(`runpod-text-${worker.id}`);
+    const updateWorkerType = (workerType, applyDefaults = false) => {
+        // The form is initialized before its card is attached to document.
+        // Use this form's own elements, not document-wide ID lookups.
+        const hostInput = hostGroup.input;
+        const portInput = portGroup.input;
+        const serverlessGroups = [
+            endpointGroup.group,
+            apiKeyGroup.group,
+            clearApiKeyGroup,
+            jobsPerRunGroup.group,
+            timeoutGroup.group,
+            testServerlessGroup,
+        ];
 
-            if (!hostGroup || !portGroup || !cudaGroup || !argsGroup || !runpodTextElem || !hostInput || !portInput) {
-                return;
-            }
+        const hideServerless = () => serverlessGroups.forEach((group) => { group.style.display = "none"; });
 
-            if (workerType === "local") {
-                hostGroup.style.display = "none";
-                portGroup.style.display = "flex";
-                cudaGroup.style.display = "flex";
-                argsGroup.style.display = "flex";
-                runpodTextElem.style.display = "none";
-            } else if (workerType === "remote") {
-                hostGroup.style.display = "flex";
-                portGroup.style.display = "flex";
-                cudaGroup.style.display = "none";
-                argsGroup.style.display = "none";
-                runpodTextElem.style.display = "none";
-                hostInput.placeholder = "e.g., 192.168.1.100";
-                if (hostInput.value === "localhost" || hostInput.value === "127.0.0.1") {
-                    hostInput.value = "";
-                }
-            } else if (workerType === "cloud") {
-                hostGroup.style.display = "flex";
-                portGroup.style.display = "flex";
-                cudaGroup.style.display = "none";
-                argsGroup.style.display = "none";
-                runpodTextElem.style.display = "block";
-                hostInput.placeholder = "e.g., your-cloud-worker.trycloudflare.com";
-                portInput.value = "443";
-                if (hostInput.value === "localhost" || hostInput.value === "127.0.0.1") {
-                    hostInput.value = "";
-                }
+        if (workerType === "local") {
+            hideServerless();
+            hostGroup.group.style.display = "none";
+            portGroup.group.style.display = "flex";
+            cudaGroup.group.style.display = "flex";
+            argsGroup.group.style.display = "flex";
+            runpodText.style.display = "none";
+        } else if (workerType === "remote") {
+            hideServerless();
+            hostGroup.group.style.display = "flex";
+            portGroup.group.style.display = "flex";
+            cudaGroup.group.style.display = "none";
+            argsGroup.group.style.display = "none";
+            runpodText.style.display = "none";
+            hostInput.placeholder = "e.g., 192.168.1.100";
+            if (applyDefaults && (hostInput.value === "localhost" || hostInput.value === "127.0.0.1")) {
+                hostInput.value = "";
             }
-        };
+        } else if (workerType === "cloud") {
+            hideServerless();
+            hostGroup.group.style.display = "flex";
+            portGroup.group.style.display = "flex";
+            cudaGroup.group.style.display = "none";
+            argsGroup.group.style.display = "none";
+            runpodText.style.display = "block";
+            hostInput.placeholder = "e.g., your-cloud-worker.trycloudflare.com";
+            if (applyDefaults) portInput.value = "443";
+            if (applyDefaults && (hostInput.value === "localhost" || hostInput.value === "127.0.0.1")) {
+                hostInput.value = "";
+            }
+        } else if (workerType === "serverless") {
+            hostGroup.group.style.display = "none";
+            portGroup.group.style.display = "none";
+            cudaGroup.group.style.display = "none";
+            argsGroup.group.style.display = "none";
+            runpodText.style.display = "none";
+            serverlessGroups.forEach((group) => { group.style.display = "flex"; });
+        }
     };
 
     typeGroup.appendChild(typeLabel);
@@ -114,6 +132,73 @@ export function createWorkerSettingsForm(ui, extension, worker) {
     argsGroup.group.style.display = (isRemoteWorker(extension, worker) || worker.type === "cloud") ? "none" : "flex";
     form.appendChild(argsGroup.group);
 
+    const endpointGroup = ui.createFormGroup("Endpoint ID:", worker.endpoint_id || "", `endpoint-id-${worker.id}`, "text", "Runpod endpoint ID");
+    endpointGroup.group.id = `endpoint-id-group-${worker.id}`;
+    endpointGroup.group.style.display = "none";
+    form.appendChild(endpointGroup.group);
+
+    const apiKeyGroup = ui.createFormGroup("Runpod API Key (write-only):", "", `api-key-${worker.id}`, "password", worker.api_key_configured ? "Leave blank to keep saved API key" : "Runpod API key");
+    apiKeyGroup.group.id = `api-key-group-${worker.id}`;
+    apiKeyGroup.input.autocomplete = "new-password";
+    apiKeyGroup.input.spellcheck = false;
+    apiKeyGroup.group.style.display = "none";
+    form.appendChild(apiKeyGroup.group);
+
+    const clearApiKeyGroup = document.createElement("div");
+    clearApiKeyGroup.id = `clear-api-key-group-${worker.id}`;
+    clearApiKeyGroup.style.cssText = "display: none; align-items: center; gap: 8px;";
+    const clearApiKeyInput = document.createElement("input");
+    clearApiKeyInput.type = "checkbox";
+    clearApiKeyInput.id = `clear-api-key-${worker.id}`;
+    const clearApiKeyLabel = document.createElement("label");
+    clearApiKeyLabel.htmlFor = clearApiKeyInput.id;
+    clearApiKeyLabel.textContent = "Clear saved API key";
+    // The backend rejects clearing the key of an enabled worker; say so up front.
+    // The form is rebuilt when the enable toggle changes, so this stays current.
+    const clearApiKeyBlockedReason = !worker.api_key_configured
+        ? "No API key is saved for this worker."
+        : worker.enabled
+            ? "Turn this worker off before clearing its API key. An enabled serverless worker needs a saved key."
+            : "";
+    clearApiKeyInput.disabled = Boolean(clearApiKeyBlockedReason);
+    clearApiKeyGroup.title = clearApiKeyBlockedReason || "Remove the saved Runpod API key when you save.";
+    clearApiKeyLabel.style.cssText = clearApiKeyBlockedReason ? "opacity: 0.5; cursor: not-allowed;" : "cursor: pointer;";
+    clearApiKeyGroup.appendChild(clearApiKeyInput);
+    clearApiKeyGroup.appendChild(clearApiKeyLabel);
+    clearApiKeyInput.onchange = () => {
+        if (clearApiKeyInput.checked) apiKeyGroup.input.value = "";
+        apiKeyGroup.input.disabled = clearApiKeyInput.checked;
+    };
+    form.appendChild(clearApiKeyGroup);
+
+    const jobsPerRunGroup = ui.createFormGroup("Images per run (1–16):", worker.jobs_per_run ?? 1, `jobs-per-run-${worker.id}`, "number");
+    jobsPerRunGroup.group.id = `jobs-per-run-group-${worker.id}`;
+    jobsPerRunGroup.input.min = "1";
+    jobsPerRunGroup.input.max = "16";
+    jobsPerRunGroup.input.step = "1";
+    jobsPerRunGroup.input.title = IMAGES_PER_RUN_TOOLTIP;
+    jobsPerRunGroup.group.title = IMAGES_PER_RUN_TOOLTIP;
+    jobsPerRunGroup.group.style.display = "none";
+    form.appendChild(jobsPerRunGroup.group);
+
+    const timeoutGroup = ui.createFormGroup("Timeout (seconds):", worker.timeout_seconds ?? 1800, `timeout-seconds-${worker.id}`, "number");
+    timeoutGroup.group.id = `timeout-seconds-group-${worker.id}`;
+    timeoutGroup.input.min = "30";
+    timeoutGroup.input.max = "86400";
+    timeoutGroup.input.step = "1";
+    timeoutGroup.group.style.display = "none";
+    form.appendChild(timeoutGroup.group);
+
+    const testServerlessButton = ui.createButton("Test Saved Endpoint", () => testServerlessWorker(extension, worker.id));
+    testServerlessButton.id = `test-serverless-${worker.id}`;
+    testServerlessButton.title = "Test the saved Runpod endpoint without submitting inference";
+    testServerlessButton.style.cssText = BUTTON_STYLES.base + BUTTON_STYLES.workerControl;
+    const testServerlessGroup = document.createElement("div");
+    testServerlessGroup.id = `serverless-test-group-${worker.id}`;
+    testServerlessGroup.style.cssText = "display: none;";
+    testServerlessGroup.appendChild(testServerlessButton);
+    form.appendChild(testServerlessGroup);
+
     const saveBtn = ui.createButton("Save", () => saveWorkerSettings(extension, worker.id), "background-color: #4a7c4a;");
     saveBtn.style.cssText = BUTTON_STYLES.base + BUTTON_STYLES.success;
 
@@ -126,9 +211,11 @@ export function createWorkerSettingsForm(ui, extension, worker) {
     const buttonGroup = ui.createButtonGroup([saveBtn, cancelBtn, deleteBtn], " margin-top: 8px;");
     form.appendChild(buttonGroup);
 
-    typeSelect.onchange = createOnChangeHandler();
+    typeSelect.onchange = (event) => updateWorkerType(event.target.value, true);
 
-    if (worker.type === "cloud") {
+    if (worker.type === "serverless") {
+        typeSelect.value = "serverless";
+    } else if (worker.type === "cloud") {
         typeSelect.value = "cloud";
         runpodText.style.display = "block";
     } else if (isRemoteWorker(extension, worker)) {
@@ -137,7 +224,7 @@ export function createWorkerSettingsForm(ui, extension, worker) {
         typeSelect.value = "local";
     }
 
-    typeSelect.dispatchEvent(new Event('change'));
+    updateWorkerType(typeSelect.value);
 
     return form;
 }

web/workerLifecycle.js

@@ -41,6 +41,41 @@ function setButtonVisibility(button, visible) {
     button.style.display = visible ? "" : "none";
 }
 
+export function formatServerlessStatus(status) {
+    if (!status) return "Checking status…";
+    if (!status.ok) return "Unavailable";
+    const jobs = (Array.isArray(status.jobs) ? status.jobs : [])
+        .map((job) => String(job?.status || "").trim().toUpperCase());
+    // Prefer current work over old ledger entries, and avoid raw provider enums.
+    const phases = [
+        ["Downloading result", ["DOWNLOADING"]],
+        ["Cancelling", ["CANCEL_REQUESTED"]],
+        ["Running", ["RUNNING", "PROCESSING", "IN_PROGRESS"]],
+        ["Starting", ["STARTING"]],
+        ["Submitting", ["SUBMITTING"]],
+        ["Queued", ["WAITING", "IN_QUEUE", "QUEUED", "PENDING"]],
+    ];
+    for (const [label, states] of phases) {
+        const count = jobs.filter((state) => states.includes(state)).length;
+        if (count) return count > 1 ? `${label} · ${count} jobs` : label;
+    }
+    // Health counts queued AND running jobs, not just the waiting queue.
+    const remaining = Number(status.queueRemaining);
+    if (Number.isFinite(remaining) && remaining > 0) {
+        return `Active · ${remaining} ${remaining === 1 ? "job" : "jobs"}`;
+    }
+    if (jobs[0] === "FAILED") return "Last job failed";
+    if (jobs[0] === "TIMED_OUT") return "Last job timed out";
+    return "Ready";
+}
+
+function updateServerlessStatusMessage(workerId, status) {
+    const messageElement = document.getElementById(`serverless-status-${workerId}`);
+    if (!messageElement) return;
+    messageElement.textContent = formatServerlessStatus(status);
+    messageElement.title = status?.message || "";
+}
+
 export async function checkAllWorkerStatuses(extension) {
     if (_statusCheckRunning || !extension.panelElement) {
         return;
@@ -136,11 +171,60 @@ export async function checkMasterStatus(extension) {
 
 // Helper to build worker URL
 export function getWorkerUrl(extension, worker, endpoint = "") {
+    if (worker?.type === "serverless") {
+        return null;
+    }
     return buildWorkerUrl(worker, endpoint, window.location);
 }
 
 export async function checkWorkerStatus(extension, worker) {
     // Assume caller ensured enabled; proceed with check
+    if (worker.type === "serverless") {
+        try {
+            const result = await extension.api.getServerlessStatus(worker.id);
+            const queueRemaining = Number(result?.queueRemaining);
+            const normalizedQueue = Number.isFinite(queueRemaining) ? Math.max(0, queueRemaining) : 0;
+            const normalizedStatus = {
+                ok: Boolean(result?.ok),
+                queueRemaining: normalizedQueue,
+                message: typeof result?.message === "string" ? result.message : "",
+                jobs: (Array.isArray(result?.jobs) ? result.jobs : []).map((job) => ({
+                    job_id: String(job?.job_id || ""),
+                    status: String(job?.status || ""),
+                    worker_id: String(job?.worker_id || ""),
+                    execution_id: String(job?.execution_id || ""),
+                })),
+            };
+            const hasActiveJobs = normalizedStatus.jobs.some((job) =>
+                /^(waiting|submitting|in_queue|queued|pending|running|processing|starting|in_progress|downloading|cancel_requested)$/i.test(job.status.trim())
+            );
+            const status = {
+                online: normalizedStatus.ok,
+                processing: normalizedQueue > 0 || hasActiveJobs,
+                queueCount: normalizedQueue,
+            };
+            extension.state.updateWorker(worker.id, { serverlessStatus: normalizedStatus });
+            extension.state.setWorkerStatus(worker.id, status);
+            updateServerlessStatusMessage(worker.id, normalizedStatus);
+            const updatedInPlace = extension.updateWorkerCard?.(worker.id, status);
+            if (!updatedInPlace) {
+                updateWorkerControls(extension, worker.id);
+            }
+        } catch (error) {
+            if (error?.name === "AbortError") return;
+            const failedStatus = { ok: false, queueRemaining: 0, message: error?.message || "Runpod status unavailable", jobs: [] };
+            extension.state.updateWorker(worker.id, { serverlessStatus: failedStatus });
+            extension.state.setWorkerStatus(worker.id, { online: false, processing: false, queueCount: 0 });
+            updateServerlessStatusMessage(worker.id, failedStatus);
+            const updatedInPlace = extension.updateWorkerCard?.(worker.id, extension.state.getWorkerStatus(worker.id));
+            if (!updatedInPlace) {
+                updateWorkerControls(extension, worker.id);
+            }
+            extension.log(`Serverless worker ${worker.id} status check failed: ${error.message}`, "debug");
+        }
+        return;
+    }
+
     const workerUrl = getWorkerUrl(extension, worker);
 
     try {
@@ -206,6 +290,9 @@ export async function checkWorkerStatus(extension, worker) {
 
 export async function launchWorker(extension, workerId) {
     const worker = extension.config.workers.find((w) => w.id === workerId);
+    if (!worker || worker.type === "serverless") {
+        return;
+    }
 
     // If worker is disabled, enable it first
     if (!worker.enabled) {
@@ -273,6 +360,9 @@ export async function launchWorker(extension, workerId) {
 
 export async function stopWorker(extension, workerId) {
     const worker = extension.config.workers.find((w) => w.id === workerId);
+    if (!worker || worker.type === "serverless") {
+        return;
+    }
     const stopBtn = document.querySelectorAll(`#controls-${workerId} button`)[1];
 
     // Provide immediate feedback
@@ -349,8 +439,12 @@ export async function loadManagedWorkers(extension) {
     try {
         const result = await extension.api.getManagedWorkers();
 
-        // Check for launching workers
+        const serverlessWorkerIds = new Set(
+            (extension.config?.workers || []).filter((worker) => worker.type === "serverless").map((worker) => String(worker.id))
+        );
+        // Managed-worker lifecycle state is ComfyUI-process-only; serverless is provider-managed.
         for (const [workerId, info] of Object.entries(result.managed_workers)) {
+            if (serverlessWorkerIds.has(String(workerId))) continue;
             extension.state.setWorkerManaged(workerId, info);
 
             // If worker is marked as launching, add to launchingWorkers set
@@ -386,6 +480,13 @@ export function updateWorkerControls(extension, workerId) {
     const stopBtn = document.getElementById(`stop-${workerId}`);
     const logBtn = document.getElementById(`log-${workerId}`);
 
+    if (worker.type === "serverless") {
+        setButtonVisibility(launchBtn, false);
+        setButtonVisibility(stopBtn, false);
+        setButtonVisibility(logBtn, false);
+        return;
+    }
+
     if (isRemoteWorker(extension, worker)) {
         setButtonVisibility(launchBtn, false);
         setButtonVisibility(stopBtn, false);
@@ -438,6 +539,9 @@ export function updateWorkerControls(extension, workerId) {
 
 export async function viewWorkerLog(extension, workerId, isRemote = false) {
     const worker = extension.config.workers.find((w) => w.id === workerId);
+    if (worker?.type === "serverless") {
+        return;
+    }
     const isRemoteLog = isRemote || (worker ? isRemoteWorker(extension, worker) : false);
     const managedInfo = extension.state.getWorker(workerId).managed;
     if (!isRemoteLog && !managedInfo?.log_file) {
@@ -498,6 +602,7 @@ export async function refreshLog(extension, workerId, silent = false) {
 
     try {
         const worker = extension.config.workers.find((w) => w.id === workerId);
+        if (worker?.type === "serverless") return;
         const isRemoteLog = worker ? isRemoteWorker(extension, worker) : false;
         const data = isRemoteLog
             ? await extension.api.getRemoteWorkerLog(workerId, 300)

web/workerSettings.js

@@ -18,7 +18,7 @@ export function isRemoteWorker(extension, worker) {
     const workerType = String(worker?.type || "").toLowerCase();
 
     // Explicit type always wins over host heuristics.
-    if (workerType === "cloud" || workerType === "remote") {
+    if (workerType === "cloud" || workerType === "remote" || workerType === "serverless") {
         return true;
     }
     if (workerType === "local") {
@@ -37,6 +37,149 @@ export function isCloudWorker(extension, worker) {
     return worker.type === "cloud";
 }
 
+// Mirrors the backend rule in utils/serverless_config.py.
+const RUNPOD_ENDPOINT_ID_RE = /^[A-Za-z0-9_-]{1,200}$/;
+
+/**
+ * Accept a pasted Runpod API URL (https://api.runpod.ai/v2/<id>/...) and keep
+ * only the endpoint ID; anything else is returned trimmed for validation.
+ */
+export function normalizeRunpodEndpointId(value) {
+    const text = String(value || "").trim();
+    const match = text.match(/^(?:https?:\/\/)?api\.runpod\.ai\/v2\/([A-Za-z0-9_-]{1,200})(?:[/?#].*)?$/i);
+    return match ? match[1] : text;
+}
+
+function showServerlessValidationError(extension, detail) {
+    extension.app.extensionManager.toast.add({
+        severity: "error",
+        summary: "Validation Error",
+        detail,
+        life: 3000,
+    });
+}
+
+async function saveServerlessWorkerSettings(extension, worker, workerId, name) {
+    const endpointId = normalizeRunpodEndpointId(document.getElementById(`endpoint-id-${workerId}`).value);
+    const apiKey = document.getElementById(`api-key-${workerId}`).value || "";
+    const clearApiKey = Boolean(document.getElementById(`clear-api-key-${workerId}`).checked);
+    const jobsPerRun = Number(document.getElementById(`jobs-per-run-${workerId}`).value);
+    const timeoutSeconds = Number(document.getElementById(`timeout-seconds-${workerId}`).value);
+
+    if (!name.trim()) {
+        showServerlessValidationError(extension, "Worker name is required");
+        return;
+    }
+    if (!endpointId) {
+        showServerlessValidationError(extension, "Endpoint ID is required for Runpod serverless workers");
+        return;
+    }
+    if (!RUNPOD_ENDPOINT_ID_RE.test(endpointId)) {
+        showServerlessValidationError(
+            extension,
+            "Enter just the Runpod endpoint ID (for example abc123xyz), not a URL. It is shown on the endpoint's page in the Runpod console.",
+        );
+        return;
+    }
+    if (!Number.isInteger(jobsPerRun) || jobsPerRun < 1 || jobsPerRun > 16) {
+        showServerlessValidationError(extension, "Images per run must be a whole number from 1 to 16");
+        return;
+    }
+    if (!Number.isInteger(timeoutSeconds) || timeoutSeconds < 30 || timeoutSeconds > 86400) {
+        showServerlessValidationError(extension, "Timeout must be an integer between 30 and 86400 seconds");
+        return;
+    }
+
+    const updateData = {
+        name: name.trim(),
+        type: "serverless",
+        provider: "runpod",
+        endpoint_id: endpointId,
+        ...(apiKey.length > 0 && !clearApiKey ? { api_key: apiKey } : {}),
+        ...(clearApiKey ? { clear_api_key: true } : {}),
+        jobs_per_run: jobsPerRun,
+        timeout_seconds: timeoutSeconds,
+        // Never enable a serverless worker as a side effect of saving credentials.
+        enabled: worker.enabled,
+    };
+
+    try {
+        await extension.api.updateWorker(workerId, updateData);
+        document.getElementById(`api-key-${workerId}`).value = "";
+
+        worker.name = name.trim();
+        worker.type = "serverless";
+        worker.provider = "runpod";
+        worker.endpoint_id = endpointId;
+        worker.jobs_per_run = jobsPerRun;
+        // Replaced by a fixed backend limit; drop any value loaded from an older config.
+        delete worker.concurrency;
+        worker.timeout_seconds = timeoutSeconds;
+        worker.api_key_configured = clearApiKey
+            ? false
+            : apiKey.length > 0 || Boolean(worker.api_key_configured);
+        // The credential is write-only: never copy it into extension config/state.
+        delete worker.api_key;
+        delete worker.host;
+        delete worker.port;
+        delete worker.cuda_device;
+        delete worker.extra_args;
+
+        extension.state.updateWorker(workerId, { enabled: worker.enabled });
+        emitWorkersChanged(extension);
+        extension.app.extensionManager.toast.add({
+            severity: "success",
+            summary: "Settings Saved",
+            detail: `Worker ${worker.name} settings updated`,
+            life: 3000,
+        });
+        extension.state.setWorkerExpanded(workerId, false);
+        if (extension.panelElement) {
+            renderSidebarContent(extension, extension.panelElement);
+        }
+    } catch (error) {
+        extension.app.extensionManager.toast.add({
+            severity: "error",
+            summary: "Save Failed",
+            detail: error.message,
+            life: 5000,
+        });
+    }
+}
+
+export async function testServerlessWorker(extension, workerId) {
+    const button = document.getElementById(`test-serverless-${workerId}`);
+    const originalText = button?.textContent;
+    if (button) {
+        button.disabled = true;
+        button.textContent = "Testing...";
+    }
+    try {
+        // This endpoint only checks the saved endpoint configuration; it does not enqueue inference.
+        const result = await extension.api.testServerlessWorker(workerId);
+        extension.app.extensionManager.toast.add({
+            severity: result?.ok ? "success" : "error",
+            summary: result?.ok ? "Runpod Endpoint Ready" : "Runpod Endpoint Test Failed",
+            detail: result?.message || (result?.ok ? "Saved endpoint is reachable" : "Endpoint test failed"),
+            life: 4000,
+        });
+        return result;
+    } catch (error) {
+        extension.app.extensionManager.toast.add({
+            severity: "error",
+            summary: "Runpod Endpoint Test Failed",
+            detail: error.message,
+            life: 5000,
+        });
+        return null;
+    } finally {
+        if (button) {
+            button.disabled = false;
+            button.textContent = originalText;
+        }
+    }
+}
+
 export async function saveWorkerSettings(extension, workerId) {
     const worker = extension.config.workers.find((w) => w.id === workerId);
     if (!worker) {
@@ -44,8 +187,20 @@ export async function saveWorkerSettings(extension, workerId) {
     }
 
     // Get form values
-    const name = document.getElementById(`name-${workerId}`).value;
     const workerType = document.getElementById(`worker-type-${workerId}`).value;
+    if (workerType === "serverless") {
+        await saveServerlessWorkerSettings(extension, worker, workerId, document.getElementById(`name-${workerId}`).value);
+        return;
+    }
+    const name = document.getElementById(`name-${workerId}`).value;
+    if (worker.type === "serverless" && worker.api_key_configured) {
+        // The backend deletes the stored key when a worker stops being serverless.
+        const proceed = confirm(
+            `Change "${worker.name}" from Serverless (Runpod) to another type?\n\n` +
+            "Its saved Runpod API key will be deleted. You would need to enter it again to switch back."
+        );
+        if (!proceed) return;
+    }
     const isRemote = workerType === "remote" || workerType === "cloud";
     const isCloud = workerType === "cloud";
     const rawHost = isRemote ? document.getElementById(`host-${workerId}`).value : window.location.hostname;
@@ -209,6 +364,19 @@ export function cancelWorkerSettings(extension, workerId) {
         document.getElementById(`port-${workerId}`).value = worker.port;
         document.getElementById(`cuda-${workerId}`).value = worker.cuda_device || 0;
         document.getElementById(`args-${workerId}`).value = worker.extra_args || "";
+        const endpointInput = document.getElementById(`endpoint-id-${workerId}`);
+        if (endpointInput) endpointInput.value = worker.endpoint_id || "";
+        const apiKeyInput = document.getElementById(`api-key-${workerId}`);
+        if (apiKeyInput) {
+            apiKeyInput.value = "";
+            apiKeyInput.disabled = false;
+        }
+        const clearApiKeyInput = document.getElementById(`clear-api-key-${workerId}`);
+        if (clearApiKeyInput) clearApiKeyInput.checked = false;
+        const jobsPerRunInput = document.getElementById(`jobs-per-run-${workerId}`);
+        if (jobsPerRunInput) jobsPerRunInput.value = worker.jobs_per_run ?? 1;
+        const timeoutInput = document.getElementById(`timeout-seconds-${workerId}`);
+        if (timeoutInput) timeoutInput.value = worker.timeout_seconds ?? 1800;
 
         // Reset remote checkbox
         const remoteCheckbox = document.getElementById(`remote-${workerId}`);

web/workerUtils.js

@@ -19,12 +19,17 @@ export async function handleWorkerOperation(extension, button, operation, succes
     setButtonStateClass("btn--working");
     
     try {
-        const urlsToProcess = extension.enabledWorkers.map(w => ({ 
-            name: w.name, 
-            url: getWorkerUrl(extension, w)
+        const workersToProcess = extension.enabledWorkers.filter((worker) =>
+            operation.endpoint !== ENDPOINTS.CLEAR_MEMORY || worker.type !== "serverless"
+        );
+        const targets = workersToProcess.map((worker) => ({
+            name: worker.name,
+            worker,
+            serverless: worker.type === "serverless",
+            url: worker.type === "serverless" ? null : getWorkerUrl(extension, worker),
         }));
-        
-        if (urlsToProcess.length === 0) {
+
+        if (targets.length === 0) {
             button.textContent = "No Workers";
             setButtonStateClass("btn--error");
             setTimeout(() => {
@@ -37,14 +42,19 @@ export async function handleWorkerOperation(extension, button, operation, succes
             return;
         }
         
-        const promises = urlsToProcess.map(target =>
-            fetch(`${target.url}${operation.endpoint}`, { 
-                method: 'POST', 
+        const promises = targets.map((target) => {
+            if (target.serverless && operation.name === "Interrupt") {
+                return extension.api.cancelServerlessWorker(target.worker.id)
+                    .then((result) => ({ ok: result?.ok !== false, name: target.name }))
+                    .catch(() => ({ ok: false, name: target.name }));
+            }
+            return fetch(`${target.url}${operation.endpoint}`, {
+                method: 'POST',
                 mode: 'cors'
             })
                 .then(response => ({ ok: response.ok, name: target.name }))
-                .catch(() => ({ ok: false, name: target.name }))
-        );
+                .catch(() => ({ ok: false, name: target.name }));
+        });
         
         const results = await Promise.all(promises);
         const failures = results.filter(r => !r.ok);

workers/detection.py

@@ -10,6 +10,8 @@ from ..utils.logging import debug_log
 
 async def is_local_worker(worker_config):
     """Check if a worker is running on the same machine as the master."""
+    if worker_config.get('type') == 'serverless':
+        return False
     host = normalize_host(worker_config.get('host', 'localhost')) or 'localhost'
     if host in ['localhost', '127.0.0.1', '0.0.0.0', ''] or worker_config.get('type') == 'local':
         return True

workers/ports.py

@@ -0,0 +1,97 @@
+"""Host-local worker port selection and launch preflight (no ComfyUI imports)."""
+import errno
+import os
+import socket
+from urllib.parse import urlsplit
+
+
+def _port_number(value):
+    try:
+        port = int(value)
+    except (TypeError, ValueError):
+        raise ValueError("Worker port must be an integer between 1 and 65535") from None
+    if isinstance(value, (bool, float)) or not 1 <= port <= 65535:
+        raise ValueError("Worker port must be an integer between 1 and 65535")
+    return port
+
+
+def _local_config(worker):
+    local_hosts = ("localhost", "127.0.0.1", "0.0.0.0", "::1", "::")
+    host = (worker.get("host") or "localhost").strip().lower()
+    if worker.get("type") == "local" or host in local_hosts:
+        return True
+    try:
+        host = urlsplit(host if "://" in host else "//" + host).hostname
+    except ValueError:
+        return False
+    return host in local_hosts
+
+
+def _reserved_ports(workers, exclude_id=None):
+    reserved = {}
+    for worker in workers:
+        if exclude_id is not None and str(worker.get("id")) == str(exclude_id):
+            continue
+        if not _local_config(worker):
+            continue
+        try:
+            port = _port_number(worker.get("port"))
+        except ValueError:
+            continue
+        reserved[port] = worker.get("name") or worker.get("id") or "another local worker"
+    return reserved
+
+
+def is_port_available(port):
+    """Match asyncio's address reuse while rejecting active IPv4/IPv6 listeners."""
+    addresses = [(socket.AF_INET, "0.0.0.0")]
+    if socket.has_ipv6:
+        addresses.append((socket.AF_INET6, "::"))
+    for family, address in addresses:
+        try:
+            with socket.socket(family, socket.SOCK_STREAM) as probe:
+                if os.name != "nt":
+                    # Like asyncio, allow a restart while old connections are
+                    # in TIME_WAIT. Do not enable SO_REUSEPORT.
+                    probe.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
+                elif hasattr(socket, "SO_EXCLUSIVEADDRUSE"):
+                    # Windows SO_REUSEADDR can steal an active listener's port.
+                    probe.setsockopt(socket.SOL_SOCKET, socket.SO_EXCLUSIVEADDRUSE, 1)
+                probe.bind((address, port))
+                probe.listen(1)
+        except OSError as exc:
+            if family == socket.AF_INET6 and exc.errno in (errno.EAFNOSUPPORT, errno.EADDRNOTAVAIL):
+                continue
+            return False
+    return True
+
+
+def allocate_worker_ports(master_port, workers, count):
+    """Select ports above the actual master, skipping reservations/listeners.
+
+    This is a snapshot, not a reservation. Launch must validate again because
+    another process can claim a suggested port before the user starts a worker.
+    """
+    master_port = _port_number(master_port)
+    reserved = _reserved_ports(workers)
+    selected = []
+    if count == 0:
+        return selected
+    for port in range(master_port + 1, 65536):
+        if port not in reserved and is_port_available(port):
+            selected.append(port)
+            if len(selected) == count:
+                return selected
+    raise ValueError(f"Not enough available worker ports above master port {master_port}; need {count}")
+
+
+def validate_worker_port(worker, master_port, workers):
+    """Reject conflicts without silently changing a configured worker port."""
+    port = _port_number(worker.get("port"))
+    if port == _port_number(master_port):
+        raise ValueError(f"Worker port {port} conflicts with the master port {master_port}; choose another worker port")
+    reserved = _reserved_ports(workers, exclude_id=worker.get("id"))
+    if port in reserved:
+        raise ValueError(f"Worker port {port} is assigned to local worker {reserved[port]}; choose another worker port")
+    if not is_port_available(port):
+        raise ValueError(f"Worker port {port} is already in use on this host; choose another worker port")

workers/process/launch_builder.py

@@ -1,4 +1,5 @@
 import glob
+import hashlib
 import os
 import shlex
 import shutil
@@ -87,6 +88,51 @@ class LaunchCommandBuilder:
             return wt_path
         return None
 
+    @staticmethod
+    def _arg_value(cmd, flag):
+        """Return the last value, matching argparse's override semantics."""
+        value = None
+        for index, arg in enumerate(cmd):
+            if arg == flag and index + 1 < len(cmd):
+                value = cmd[index + 1]
+            elif arg.startswith(flag + "="):
+                value = arg.split("=", 1)[1]
+        return value
+
+    def _add_worker_database(self, cmd, worker_config, comfy_root):
+        args = self._get_runtime_args()
+        # The parsed namespace advertises support without launching ComfyUI
+        # (or importing another checkout's argument parser).
+        if args is None or not hasattr(args, "database_url"):
+            return
+        if any(arg.split("=", 1)[0] in ("--database-url", "--disable-assets") for arg in cmd):
+            return
+
+        user_directory = self._arg_value(cmd, "--user-directory")
+        base_directory = self._arg_value(cmd, "--base-directory")
+        if not user_directory:
+            user_directory = os.path.join(base_directory or comfy_root, "user")
+        if not os.path.isabs(user_directory):
+            # Popen uses comfy_root as cwd, which can differ from the master's.
+            user_directory = os.path.join(comfy_root, user_directory)
+        database_directory = os.path.abspath(os.path.join(user_directory, "distributed", "workers"))
+        # Hash the immutable ID: names/GPU/ports may change, and IDs must not
+        # become filesystem paths or collide after filename sanitization.
+        worker_id = str(worker_config["id"])
+        filename = hashlib.sha256(worker_id.encode("utf-8")).hexdigest() + ".db"
+        database_path = os.path.join(database_directory, filename).replace(os.sep, "/")
+        # Use the same URL codec as ComfyUI; raw '?' and '%xx' can otherwise
+        # truncate/decode the path and make distinct workers share a database.
+        from sqlalchemy.engine import URL, make_url
+        database_url = URL.create("sqlite", database=database_path).render_as_string()
+        if make_url(database_url).database != database_path:
+            raise ValueError(
+                "Installed SQLAlchemy cannot safely encode the worker database path; "
+                "use a user directory without '?' or an explicit --database-url with a safe path"
+            )
+        os.makedirs(database_directory, exist_ok=True)
+        cmd.extend(["--database-url", database_url])
+
     def build_launch_command(self, worker_config, comfy_root):
         """Build the command to launch a worker."""
         main_py = os.path.join(comfy_root, "main.py")
@@ -141,4 +187,7 @@ class LaunchCommandBuilder:
                         raise ValueError(f"Invalid characters in extra_args: {arg}. Forbidden: {forbidden}")
                 cmd.extend(extra_args_list)
 
+        if int(self._arg_value(cmd, "--port")) != int(worker_config["port"]):
+            raise ValueError("extra_args must not override the configured worker port; set the port in the UI/config instead")
+        self._add_worker_database(cmd, worker_config, comfy_root)
         return cmd

workers/process/lifecycle.py

@@ -7,7 +7,9 @@ import time
 from ...utils.config import load_config, save_config
 from ...utils.constants import PROCESS_TERMINATION_TIMEOUT, PROCESS_WAIT_TIMEOUT, WORKER_CHECK_INTERVAL
 from ...utils.logging import debug_log, log
+from ...utils.network import get_server_port
 from ...utils.process import get_python_executable, is_process_alive, terminate_process
+from ..ports import validate_worker_port
 
 try:
     import psutil
@@ -28,6 +30,17 @@ class ProcessLifecycle:
         """Launch a worker process with logging."""
         _ = show_window  # Kept for API compatibility.
         comfy_root = self._manager.find_comfy_root()
+        config = load_config()
+        try:
+            master_port = get_server_port()
+        except AttributeError:
+            master_port = None
+        if master_port is None:
+            # The auto-launch timer can fire during custom-node imports, before
+            # PromptServer assigns its port. Still reserve the configured port.
+            from comfy.cli_args import args
+            master_port = args.port
+        validate_worker_port(worker_config, master_port, config.get("workers", []))
 
         env = os.environ.copy()
         env["CUDA_VISIBLE_DEVICES"] = str(worker_config.get("cuda_device", 0))

workers/process_manager.py

@@ -22,6 +22,8 @@ class WorkerProcessManager:
         return self._launch_builder.build_launch_command(worker_config, comfy_root)
 
     def launch_worker(self, worker_config, show_window=False):
+        if worker_config.get("type") == "serverless":
+            raise ValueError("Serverless pools cannot be launched as local processes")
         return self._lifecycle.launch_worker(worker_config, show_window=show_window)
 
     def stop_worker(self, worker_id):

workers/startup.py

@@ -35,6 +35,8 @@ def auto_launch_workers():
             launched_count = 0
             
             for worker in workers:
+                if worker.get('type') == 'serverless':
+                    continue
                 if worker.get('enabled', False):
                     worker_id = worker.get('id')
                     worker_name = worker.get('name', f'Worker {worker_id}')