Merge pull request #1174 from matrix-org/erikj/email_push_noop

Reduce redundant database work in email pusher

synapse/push/emailpusher.py

@@ -150,6 +150,10 @@ class EmailPusher(object):
 
         soonest_due_at = None
 
+        if not unprocessed:
+            yield self.save_last_stream_ordering_and_success(self.max_stream_ordering)
+            return
+
         for push_action in unprocessed:
             received_at = push_action['received_ts']
             if received_at is None:

synapse/push/mailer.py

@@ -372,7 +372,7 @@ class Mailer(object):
                     state_event_id = room_state_ids[room_id][
                         ("m.room.member", event.sender)
                     ]
-                    state_event = yield self.get_event(state_event_id)
+                    state_event = yield self.store.get_event(state_event_id)
                     sender_name = name_from_member_event(state_event)
 
                 if sender_name is not None and room_name is not None: