Add lock on plex server library cache refreshing

plex_auto_languages/plex_server_cache.py

@@ -18,6 +18,7 @@
 class PlexServerCache():
 
     def __init__(self, plex: PlexServer):
+        self._is_refreshing = False
         self._encoder = DateTimeEncoder()
         self._plex = plex
         self._cache_file_path = self._get_cache_file_path()
@@ -51,6 +52,10 @@ def should_process_recently_updated(self, episode_id: str):
         return True
 
     def refresh_library_cache(self):
+        if self._is_refreshing:
+            logger.debug("[Cache] The library cache is already being refreshed")
+            return [], []
+        self._is_refreshing = True
         logger.debug("[Cache] Refreshing library cache")
         added = []
         updated = []
@@ -67,6 +72,7 @@ def refresh_library_cache(self):
         logger.debug("[Cache] Done refreshing library cache")
         self._last_refresh = datetime.now()
         self.save()
+        self._is_refreshing = False
         return added, updated
 
     def _get_cache_file_path(self):

tests/test_plex_server_cache.py

@@ -10,6 +10,11 @@ def test_episode_parts(plex):
     assert len(plex.cache.episode_parts) == 46
 
 
+def test_is_refreshing(plex):
+    plex.cache._is_refreshing = True
+    assert plex.cache.refresh_library_cache() == ([], [])
+
+
 def test_cache_dir(plex):
     mocked_path = "/tmp/mocked_cache_dir"
     plex.config._config["data_dir"] = mocked_path