Graceful invalid queue (#2391)

* return none rather than raise an error on bad deserialize version.

* Python 3.8 compat I somehow missed.

* py 3.8 compat with proper formatting.

* now actually use the type alias.

* i am scatter brain today. :)

musicbot/entry.py

@@ -284,9 +284,11 @@ def _deserialize(
 
         vernum: Optional[int] = raw_json.get("version", None)
         if not vernum:
-            raise InvalidDataError("Entry data is missing version number.")
+            log.error("Entry data is missing version number, cannot deserialize.")
+            return None
         if vernum != URLPlaylistEntry.SERIAL_VERSION:
-            raise InvalidDataError("Entry data has the wrong version number.")
+            log.error("Entry data has the wrong version number, cannot deserialize.")
+            return None
 
         try:
             info = YtdlpResponseDict(raw_json["info"])
@@ -720,9 +722,11 @@ def _deserialize(
 
         vernum = raw_json.get("version", None)
         if not vernum:
-            raise InvalidDataError("Entry data is missing version number.")
+            log.error("Entry data is missing version number, cannot deserialize.")
+            return None
         if vernum != URLPlaylistEntry.SERIAL_VERSION:
-            raise InvalidDataError("Entry data has the wrong version number.")
+            log.error("Entry data has the wrong version number, cannot deserialize.")
+            return None
 
         try:
             info = YtdlpResponseDict(raw_json["info"])

musicbot/player.py

@@ -19,6 +19,10 @@
     from .bot import MusicBot
     from .playlist import Playlist
 
+    AsyncFuture = asyncio.Future[Any]
+else:
+    AsyncFuture = asyncio.Future
+
 # Type alias
 EntryTypes = Union[URLPlaylistEntry, StreamPlaylistEntry]
 
@@ -95,7 +99,7 @@ def __init__(
         self._play_lock = asyncio.Lock()
         self._current_player: Optional[VoiceClient] = None
         self._current_entry: Optional[EntryTypes] = None
-        self._stderr_future: Optional[asyncio.Future[Any]] = None
+        self._stderr_future: Optional[AsyncFuture] = None
 
         self._source: Optional[SourcePlaybackCounter] = None
 
@@ -524,7 +528,7 @@ def progress(self) -> float:
 # TODO: I need to add a check if the event loop is closed?
 
 
-def filter_stderr(stderr: io.BytesIO, future: asyncio.Future[Any]) -> None:
+def filter_stderr(stderr: io.BytesIO, future: AsyncFuture) -> None:
     """
     Consume a `stderr` bytes stream and check it for errors or warnings.
     Set the given `future` with either an error found in the stream or