Merge branch 'develop' into mv/join-during-fast-join

synapse/handlers/federation.py

@@ -598,6 +598,24 @@ async def do_invite_join(
 
         self._federation_event_handler.room_queues[room_id] = []
 
+        is_host_joined = await self.store.is_host_joined(room_id, self.server_name)
+
+        if not is_host_joined:
+            # We may have old forward extremities lying around if the homeserver left
+            # the room completely in the past. Clear them out.
+            #
+            # Note that this check-then-clear is subject to races where
+            #  * the homeserver is in the room and stops being in the room just after
+            #    the check. We won't reset the forward extremities, but that's okay,
+            #    since they will be almost up to date.
+            #  * the homeserver is not in the room and starts being in the room just
+            #    after the check. This can't happen, since `RoomMemberHandler` has a
+            #    linearizer lock which prevents concurrent remote joins into the same
+            #    room.
+            # In short, the races either have an acceptable outcome or should be
+            # impossible.
+            await self._clean_room_for_join(room_id)
+
         try:
             # Try the host we successfully got a response to /make_join/
             # request first.
@@ -639,77 +657,32 @@ async def do_invite_join(
                 logger.debug("do_invite_join auth_chain: %s", auth_chain)
                 logger.debug("do_invite_join state: %s", state)
 
-            await self._clean_room_for_join(room_id)
-
-            # if this is the first time we've joined this room, it's time to add
-            # a row to `rooms` with the correct room version. If there's already a
-            # row there, we should override it, since it may have been populated
-            # based on an invite request which lied about the room version.
-            #
-            # federation_client.send_join has already checked that the room
-            # version in the received create event is the same as room_version_obj,
-            # so we can rely on it now.
-            #
-            await self.store.upsert_room_on_join(
-                room_id=room_id,
-                room_version=room_version_obj,
-                state_events=state,
-            )
-
-            already_partially_joined = await self.store.is_partial_state_room(room_id)
-            if ret.partial_state and not already_partially_joined:
-                # Mark the room as having partial state.
-                # The background process is responsible for unmarking this flag,
-                # even if the join fails.
-                await self.store.store_partial_state_room(
+                logger.debug("do_invite_join event: %s", event)
+
+                # if this is the first time we've joined this room, it's time to add
+                # a row to `rooms` with the correct room version. If there's already a
+                # row there, we should override it, since it may have been populated
+                # based on an invite request which lied about the room version.
+                #
+                # federation_client.send_join has already checked that the room
+                # version in the received create event is the same as room_version_obj,
+                # so we can rely on it now.
+                #
+                await self.store.upsert_room_on_join(
                     room_id=room_id,
                     room_version=room_version_obj,
                     state_events=state,
                 )
 
-            try:
-                max_stream_id = (
-                    await self._federation_event_handler.process_remote_join(
-                        origin,
-                        room_id,
-                        auth_chain,
-                        state,
-                        event,
-                        room_version_obj,
-                        partial_state=ret.partial_state,
-                    )
-                )
-            except PartialStateConflictError as e:
-                # The homeserver was already in the room and it is no longer partial
-                # stated. We ought to be doing a local join instead.
-                # TODO(faster_joins): `_should_perform_remote_join` suggests that we may
-                #   do a remote join for restricted rooms even if we have full state.
-                logger.error(
-                    "Room %s was un-partial stated while processing remote join.",
-                    room_id,
-                )
-                raise e
-            else:
-                # Record the join event id for future use (when we finish the full
-                # join). We have to do this after persisting the event to keep foreign
-                # key constraints intact.
-                if ret.partial_state:
-                    await self.store.write_partial_state_rooms_join_event_id(
-                        room_id, event.event_id
-                    )
-            finally:
-                # Always kick off the background process that asynchronously fetches
-                # state for the room.
-                # If the join failed, the background process is responsible for
-                # cleaning up — including unmarking the room as a partial state room.
-                if ret.partial_state and not already_partially_joined:
-                    # Kick off the process of asynchronously fetching the state for this
-                    # room.
-                    run_as_background_process(
-                        desc="sync_partial_state_room",
-                        func=self._sync_partial_state_room,
-                        initial_destination=origin,
-                        other_destinations=ret.servers_in_room,
+                if ret.partial_state and not already_partial_state_room:
+                    # Mark the room as having partial state.
+                    # The background process is responsible for unmarking this flag,
+                    # even if the join fails.
+                    # TODO(faster_joins):
+                    #     We may want to reset the partial state info if it's from an
+                    #     old, failed partial state join.
+                    #     https://github.com/matrix-org/synapse/issues/13000
+                    await self.store.store_partial_state_room(
                         room_id=room_id,
                         servers=ret.servers_in_room,
                         device_lists_stream_id=self.store.get_device_stream_token(),