listener: Try and protect actors against "bad" events

mopidy/core/listener.py

@@ -31,7 +31,8 @@ class CoreListener(listener.Listener):
         :type event: string
         :param kwargs: any other arguments to the specific event handlers
         """
-        getattr(self, event)(**kwargs)
+        # Just delegate to parent, entry mostly for docs.
+        super(CoreListener, self).on_event(event, **kwargs)
 
     def track_playback_paused(self, tl_track, time_position):
         """

mopidy/listener.py

@@ -41,4 +41,8 @@ class Listener(object):
         :type event: string
         :param kwargs: any other arguments to the specific event handlers
         """
-        getattr(self, event)(**kwargs)
+        try:
+            getattr(self, event)(**kwargs)
+        except Exception:
+            # Ensure we don't crash the actor due to "bad" events.
+            logger.exception('Triggering event failed: %s', event)

mopidy/mpd/dispatcher.py

@@ -47,6 +47,7 @@ class MpdDispatcher(object):
         return self._call_next_filter(request, response, filter_chain)
 
     def handle_idle(self, subsystem):
+        # TODO: validate against mopidy/mpd/protocol/status.SUBSYSTEMS
         self.context.events.add(subsystem)
 
         subsystems = self.context.subscriptions.intersection(