Refactor the exporter into a package-backed module layout.

Split the previous monolithic implementation into focused modules for CLI handling, workflow loading, runtime bootstrap, load ordering, planning, rendering, and file I/O. Keep the public compatibility surface intact by preserving the legacy top-level wrapper while adding  as the documented entrypoint. This reduces cross-cutting coupling inside the exporter and makes the runtime/bootstrap behavior easier to evolve without carrying unrelated concerns in one file.

comfyui_to_python/node_runtime.py

@@ -0,0 +1,133 @@
+import os
+import sys
+from typing import Any, Mapping, Sequence, Union
+
+
+def find_path(name: str, path: str = None) -> str:
+    """Recursively search parent folders until the named entry is found."""
+    if path is None:
+        path = os.getcwd()
+
+    if name in os.listdir(path):
+        path_name = os.path.join(path, name)
+        print(f"{name} found: {path_name}")
+        return path_name
+
+    parent_directory = os.path.dirname(path)
+    if parent_directory == path:
+        return None
+
+    return find_path(name, parent_directory)
+
+
+def get_comfyui_path() -> str:
+    """Return the configured ComfyUI path, preferring COMFYUI_PATH when set."""
+    comfyui_path = os.environ.get("COMFYUI_PATH")
+    if comfyui_path:
+        return comfyui_path
+    return find_path("ComfyUI")
+
+
+def add_comfyui_directory_to_sys_path() -> None:
+    """Add the ComfyUI checkout to sys.path."""
+    comfyui_path = get_comfyui_path()
+    if comfyui_path is not None and os.path.isdir(comfyui_path):
+        if comfyui_path in sys.path:
+            sys.path.remove(comfyui_path)
+        sys.path.insert(0, comfyui_path)
+        print(f"'{comfyui_path}' added to sys.path")
+
+
+def add_extra_model_paths() -> None:
+    """Load ComfyUI extra model paths configuration when available."""
+    try:
+        from main import load_extra_path_config
+    except ImportError:
+        print(
+            "Could not import load_extra_path_config from main.py. Looking in utils.extra_config instead."
+        )
+        from utils.extra_config import load_extra_path_config
+
+    extra_model_paths = find_path("extra_model_paths.yaml")
+    if extra_model_paths is not None:
+        load_extra_path_config(extra_model_paths)
+    else:
+        print("Could not find the extra_model_paths config file.")
+
+
+def bootstrap_comfyui_runtime() -> None:
+    """Mirror the allocator-related ComfyUI startup steps before torch import."""
+    add_comfyui_directory_to_sys_path()
+
+    import comfy.options
+
+    comfy.options.enable_args_parsing()
+
+    from comfy.cli_args import args
+
+    if os.name == "nt":
+        os.environ["MIMALLOC_PURGE_DELAY"] = "0"
+
+    if args.default_device is not None:
+        default_dev = args.default_device
+        devices = list(range(32))
+        devices.remove(default_dev)
+        devices.insert(0, default_dev)
+        devices = ",".join(map(str, devices))
+        os.environ["CUDA_VISIBLE_DEVICES"] = str(devices)
+        os.environ["HIP_VISIBLE_DEVICES"] = str(devices)
+
+    if args.cuda_device is not None:
+        os.environ["CUDA_VISIBLE_DEVICES"] = str(args.cuda_device)
+        os.environ["HIP_VISIBLE_DEVICES"] = str(args.cuda_device)
+        os.environ["ASCEND_RT_VISIBLE_DEVICES"] = str(args.cuda_device)
+
+    if args.oneapi_device_selector is not None:
+        os.environ["ONEAPI_DEVICE_SELECTOR"] = args.oneapi_device_selector
+
+    if args.deterministic and "CUBLAS_WORKSPACE_CONFIG" not in os.environ:
+        os.environ["CUBLAS_WORKSPACE_CONFIG"] = ":4096:8"
+
+    import cuda_malloc
+
+    if "rocm" in cuda_malloc.get_torch_version_noimport():
+        os.environ["OCL_SET_SVM_SIZE"] = "262144"
+
+
+def import_custom_nodes() -> None:
+    """Initialize ComfyUI custom nodes in the exporter runtime."""
+    comfyui_path = get_comfyui_path()
+    if comfyui_path and comfyui_path not in sys.path:
+        sys.path.insert(0, comfyui_path)
+
+    import asyncio
+    import execution
+    from nodes import init_extra_nodes
+
+    if comfyui_path in sys.path:
+        sys.path.remove(comfyui_path)
+    sys.path.insert(0, comfyui_path)
+
+    import server
+
+    loop = asyncio.new_event_loop()
+    asyncio.set_event_loop(loop)
+    server_instance = server.PromptServer(loop)
+    execution.PromptQueue(server_instance)
+    asyncio.run(init_extra_nodes())
+
+
+def get_node_class_mappings() -> dict:
+    """Load ComfyUI node mappings on demand."""
+    add_comfyui_directory_to_sys_path()
+    from nodes import NODE_CLASS_MAPPINGS
+
+    return NODE_CLASS_MAPPINGS
+
+
+def get_value_at_index(obj: Union[Sequence, Mapping], index: int) -> Any:
+    """Return a sequence or mapping result item by index."""
+    try:
+        return obj[index]
+    except KeyError:
+        return obj["result"][index]