add rescan lock

tubearchivist/home/apps.py

@@ -38,7 +38,13 @@ def make_folders():
 
 def release_lock():
     """make sure there are no leftover locks set in redis on container start"""
-    all_locks = ["manual_import", "downloading", "dl_queue", "dl_queue_id"]
+    all_locks = [
+        "manual_import",
+        "downloading",
+        "dl_queue",
+        "dl_queue_id",
+        "rescan",
+    ]
     for lock in all_locks:
         response = RedisArchivist().del_message(lock)
         if response:

tubearchivist/home/tasks.py

@@ -45,17 +45,28 @@ def update_subscribed():
         "title": "Start rescanning channels and playlists.",
     }
     RedisArchivist().set_message("progress:download", message)
+
+    have_lock = False
+    my_lock = RedisArchivist().get_lock("rescan")
+
+    try:
+        have_lock = my_lock.acquire(blocking=False)
+        if have_lock:
             channel_handler = ChannelSubscription()
             missing_from_channels = channel_handler.find_missing()
             playlist_handler = PlaylistSubscription()
             missing_from_playlists = playlist_handler.find_missing()
-    missing_videos = missing_from_channels + missing_from_playlists
-    if missing_videos:
+            missing = missing_from_channels + missing_from_playlists
+            if missing:
                 pending_handler = PendingList()
-        all_videos_added = pending_handler.add_to_pending(missing_videos)
+                all_videos_added = pending_handler.add_to_pending(missing)
                 ThumbManager().download_vid(all_videos_added)
-    # check if reindex is needed
-    check_reindex.delay()
+        else:
+            print("Did not acquire rescan lock.")
+
+    finally:
+        if have_lock:
+            my_lock.release()
 
 
 @shared_task(name="download_pending")