Fix missing cache invalidation in application service code (#14670)

#11915 introduced the `@cached` `is_interested_in_room` method in
Synapse 1.55.0, which depends upon `get_aliases_for_room`. Add a missing
cache invalidation callback so that the `is_interested_in_room` cache is
invalidated when `get_aliases_for_room` is invalidated.

#13787 made `get_rooms_for_user` `@cached`. Add a missing cache
invalidation callback so that the `is_interested_in_presence` cache is
invalidated when `get_rooms_for_user` is invalidated.

Signed-off-by: Sean Quah <seanq@matrix.org>

changelog.d/14670.bugfix

+Fix bugs introduced in 1.55.0 and 1.69.0 where application services would not be notified of events in the correct rooms, due to stale caches.

synapse/appservice/__init__.py

@@ -245,7 +245,9 @@ class ApplicationService:
             return True
 
         # likewise with the room's aliases (if it has any)
-        alias_list = await store.get_aliases_for_room(room_id)
+        alias_list = await store.get_aliases_for_room(
+            room_id, on_invalidate=cache_context.invalidate
+        )
         for alias in alias_list:
             if self.is_room_alias_in_namespace(alias):
                 return True
@@ -311,7 +313,9 @@ class ApplicationService:
         # Find all the rooms the sender is in
         if self.is_interested_in_user(user_id.to_string()):
             return True
-        room_ids = await store.get_rooms_for_user(user_id.to_string())
+        room_ids = await store.get_rooms_for_user(
+            user_id.to_string(), on_invalidate=cache_context.invalidate
+        )
 
         # Then find out if the appservice is interested in any of those rooms
         for room_id in room_ids: