Faster room joins: make `/joined_members` block whilst the room is partial stated. (#13514)

2 files changed, 16 insertions, 0 deletions

diff --git a/synapse/storage/controllers/state.py b/synapse/storage/controllers/state.py
index 0d480f1014..0c78eb735e 100644
--- a/synapse/storage/controllers/state.py
+++ b/synapse/storage/controllers/state.py
@@ -30,6 +30,7 @@ from typing import (
 from synapse.api.constants import EventTypes
 from synapse.events import EventBase
 from synapse.logging.opentracing import trace
+from synapse.storage.roommember import ProfileInfo
 from synapse.storage.state import StateFilter
 from synapse.storage.util.partial_state_events_tracker import (
     PartialCurrentStateTracker,
@@ -506,3 +507,15 @@ class StateStorageController:
         await self._partial_state_room_tracker.await_full_state(room_id)
 
         return await self.stores.main.get_current_hosts_in_room(room_id)
+
+    async def get_users_in_room_with_profiles(
+        self, room_id: str
+    ) -> Dict[str, ProfileInfo]:
+        """
+        Get the current users in the room with their profiles.
+        If the room is currently partial-stated, this will block until the room has
+        full state.
+        """
+        await self._partial_state_room_tracker.await_full_state(room_id)
+
+        return await self.stores.main.get_users_in_room_with_profiles(room_id)
diff --git a/synapse/storage/databases/main/roommember.py b/synapse/storage/databases/main/roommember.py
index 93ff4816c8..5e5f607a14 100644
--- a/synapse/storage/databases/main/roommember.py
+++ b/synapse/storage/databases/main/roommember.py
@@ -283,6 +283,9 @@ class RoomMemberWorkerStore(EventsWorkerStore):
 
         Returns:
             A mapping from user ID to ProfileInfo.
+
+        Preconditions:
+          - There is full state available for the room (it is not partial-stated).
         """
 
         def _get_users_in_room_with_profiles(