fix: Model hashing fixes (#62)

* make sure hashing is done only when the models are selected

* fix cache file not being written, if it did not exist

---------

Co-authored-by: Frost Ming <me@frostming.com>

nodes/api.py

@@ -15,14 +15,14 @@ from fnmatch import fnmatch
 from pathlib import Path
 from typing import Any, Union
 
-import folder_paths
 from aiohttp import web
-from server import PromptServer
-
 from comfy_pack.hash import async_batch_get_sha256
 from comfy_pack.model_helper import alookup_model_source
 from comfy_pack.package import build_bento
 
+import folder_paths
+from server import PromptServer
+
 ZPath = Union[Path, zipfile.Path]
 TEMP_FOLDER = Path(__file__).parent.parent / "temp"
 COMFY_PACK_DIR = Path(__file__).parent.parent / "src" / "comfy_pack"
@@ -136,12 +136,23 @@ async def _get_models(
         for line in stdout.decode().splitlines()
         if not os.path.basename(line.strip().strip('"').replace('\\\\', '/')).startswith(".")
     ]
+
+    # Only compute hashes for referenced models
+    to_include = []
+    if model_filter:
+        for m1 in model_filter:
+            for m2 in model_filenames:
+                if m1 in m2:
+                    to_include.append(m2)
+    else:
+        to_include = model_filenames
+
     model_hashes = await async_batch_get_sha256(
-        model_filenames,
+        to_include,
         cache_only=not (ensure_sha or store_models),
     )
 
-    for filename in model_filenames:
+    for filename in to_include:
         # Skip if file doesn't exist
         if not os.path.exists(filename):
             continue

src/comfy_pack/hash.py

@@ -113,7 +113,12 @@ async def async_batch_get_sha256(
     try:
         with SHA_CACHE_FILE.open("r") as f:
             cache = json.load(f)
-        cache.update(new_cache)
+    except (IOError, OSError):
+        cache = {}
+
+    cache.update(new_cache)
+
+    try:
         with SHA_CACHE_FILE.open("w") as f:
             json.dump(cache, f, indent=2)
     except (IOError, OSError):