add SD_NO_CACHE env variable

Signed-off-by: Vladimir Mandic <mandic00@live.com>

CHANGELOG.md

@@ -83,6 +83,7 @@
 
 ### Fixes  
 
+- add `SD_NO_CACHE=true` env variable to disable file/folder caching  
 - update `diffusers`  
 - fix README links  
 - fix sdxl controlnet single-file loader  

modules/files_cache.py

@@ -6,6 +6,7 @@ from typing import Callable, Dict, Iterator, List, Optional, Union
 from installer import log
 
 
+do_cache_folders = os.environ.get('SD_NO_CACHE', None) is None
 class Directory: # forward declaration
     ...
 
@@ -87,8 +88,6 @@ class Directory(Directory): # pylint: disable=E0102
         return not self.is_directory or self.mtime != self.live_mtime
 
 
-
-
 class DirectoryCache(UserDict, DirectoryCollection):
     def __delattr__(self, directory_path: str) -> None:
         directory: Directory = get_directory(directory_path, fetch=False)
@@ -126,7 +125,7 @@ def clean_directory(directory: Directory, /, recursive: RecursiveType=False) ->
     return is_clean
 
 
-def get_directory(directory_or_path: str, /, fetch:bool=True) -> Union[Directory, None]:
+def get_directory(directory_or_path: str, /, fetch: bool=True) -> Union[Directory, None]:
     if isinstance(directory_or_path, Directory):
         if directory_or_path.is_directory:
             return directory_or_path
@@ -136,8 +135,9 @@ def get_directory(directory_or_path: str, /, fetch:bool=True) -> Union[Directory
     if not cache_folders.get(directory_or_path, None):
         if fetch:
             directory = fetch_directory(directory_path=directory_or_path)
-            if directory:
+            if directory and do_cache_folders:
                 cache_folders[directory_or_path] = directory
+            return directory
     else:
         clean_directory(cache_folders[directory_or_path])
     return cache_folders[directory_or_path] if directory_or_path in cache_folders else None

modules/shared.py

@@ -16,7 +16,7 @@ import fasteners
 import orjson
 import diffusers
 from rich.console import Console
-from modules import errors, devices, shared_items, shared_state, cmd_args, theme, history
+from modules import errors, devices, shared_items, shared_state, cmd_args, theme, history, files_cache
 from modules.paths import models_path, script_path, data_path, sd_configs_path, sd_default_config, sd_model_file, default_sd_model_file, extensions_dir, extensions_builtin_dir # pylint: disable=W0611
 from modules.dml import memory_providers, default_memory_provider, directml_do_hijack
 from modules.onnx_impl import initialize_onnx, execution_providers
@@ -238,6 +238,8 @@ cpu_memory = round(psutil.virtual_memory().total / 1024 / 1024 / 1024, 2)
 mem_stat = memory_stats()
 gpu_memory = mem_stat['gpu']['total'] if "gpu" in mem_stat else 0
 native = backend == Backend.DIFFUSERS
+if not files_cache.do_cache_folders:
+    log.warning('File cache disabled: ')
 
 
 class OptionInfo: