| import threading | |
| import diskcache | |
| import os | |
| from modules.paths import data_path | |
| cache_lock = threading.Lock() | |
| cache_dir = os.environ.get("SD_WEBUI_CACHE_DIR", os.path.join(data_path, "cache")) | |
| caches = {} | |
| dump_cache = lambda: None | |
| """does nothing since diskcache""" | |
| def cache(subsection): | |
| """ | |
| Retrieves or initializes a cache for a specific subsection. | |
| Parameters: | |
| subsection (str): The subsection identifier for the cache. | |
| Returns: | |
| diskcache.Cache: The cache data for the specified subsection. | |
| """ | |
| cache_obj = caches.get(subsection) | |
| if not cache_obj: | |
| with cache_lock: | |
| cache_obj = caches.get(subsection) | |
| if not cache_obj: | |
| cache_obj = diskcache.Cache(os.path.join(cache_dir, subsection)) | |
| caches[subsection] = cache_obj | |
| return cache_obj | |
| def cached_data_for_file(subsection, title, filename, func): | |
| """ | |
| Retrieves or generates data for a specific file, using a caching mechanism. | |
| Parameters: | |
| subsection (str): The subsection of the cache to use. | |
| title (str): The title of the data entry in the subsection of the cache. | |
| filename (str): The path to the file to be checked for modifications. | |
| func (callable): A function that generates the data if it is not available in the cache. | |
| Returns: | |
| dict or None: The cached or generated data, or None if data generation fails. | |
| The function implements a caching mechanism for data stored in files. | |
| It checks if the data associated with the given `title` is present in the cache and compares the | |
| modification time of the file with the cached modification time. If the file has been modified, | |
| the cache is considered invalid and the data is regenerated using the provided `func`. | |
| Otherwise, the cached data is returned. | |
| If the data generation fails, None is returned to indicate the failure. Otherwise, the generated | |
| or cached data is returned as a dictionary. | |
| """ | |
| existing_cache = cache(subsection) | |
| ondisk_mtime = os.path.getmtime(filename) | |
| entry = existing_cache.get(title) | |
| if entry: | |
| cached_mtime = entry.get("mtime", 0) | |
| if ondisk_mtime > cached_mtime: | |
| entry = None | |
| if not entry or "value" not in entry: | |
| value = func() | |
| if value is None: | |
| return None | |
| entry = {"mtime": ondisk_mtime, "value": value} | |
| existing_cache[title] = entry | |
| dump_cache() | |
| return entry["value"] | |