From e8318a433356413648bd180dcfc69c29ca319fc6 Mon Sep 17 00:00:00 2001
From: Erik Johnston <erik@matrix.org>
Date: Tue, 27 Sep 2022 13:01:08 +0100
Subject: Handle the case of remote users leaving a partial join room for
 device lists (#13885)

---
 synapse/storage/controllers/persist_events.py | 71 ---------------------------
 1 file changed, 71 deletions(-)

(limited to 'synapse/storage/controllers')

diff --git a/synapse/storage/controllers/persist_events.py b/synapse/storage/controllers/persist_events.py
index 501dbbc990..709cb792ed 100644
--- a/synapse/storage/controllers/persist_events.py
+++ b/synapse/storage/controllers/persist_events.py
@@ -598,11 +598,6 @@ class EventsPersistenceStorageController:
             # room
             state_delta_for_room: Dict[str, DeltaState] = {}
 
-            # Set of remote users which were in rooms the server has left or who may
-            # have left rooms the server is in. We should check if we still share any
-            # rooms and if not we mark their device lists as stale.
-            potentially_left_users: Set[str] = set()
-
             if not backfilled:
                 with Measure(self._clock, "_calculate_state_and_extrem"):
                     # Work out the new "current state" for each room.
@@ -716,8 +711,6 @@ class EventsPersistenceStorageController:
                                 room_id,
                                 ev_ctx_rm,
                                 delta,
-                                current_state,
-                                potentially_left_users,
                             )
                             if not is_still_joined:
                                 logger.info("Server no longer in room %s", room_id)
@@ -725,20 +718,6 @@ class EventsPersistenceStorageController:
                                 current_state = {}
                                 delta.no_longer_in_room = True
 
-                            # Add all remote users that might have left rooms.
-                            potentially_left_users.update(
-                                user_id
-                                for event_type, user_id in delta.to_delete
-                                if event_type == EventTypes.Member
-                                and not self.is_mine_id(user_id)
-                            )
-                            potentially_left_users.update(
-                                user_id
-                                for event_type, user_id in delta.to_insert.keys()
-                                if event_type == EventTypes.Member
-                                and not self.is_mine_id(user_id)
-                            )
-
                             state_delta_for_room[room_id] = delta
 
             await self.persist_events_store._persist_events_and_state_updates(
@@ -749,8 +728,6 @@ class EventsPersistenceStorageController:
                 inhibit_local_membership_updates=backfilled,
             )
 
-            await self._handle_potentially_left_users(potentially_left_users)
-
         return replaced_events
 
     async def _calculate_new_extremities(
@@ -1126,8 +1103,6 @@ class EventsPersistenceStorageController:
         room_id: str,
         ev_ctx_rm: List[Tuple[EventBase, EventContext]],
         delta: DeltaState,
-        current_state: Optional[StateMap[str]],
-        potentially_left_users: Set[str],
     ) -> bool:
         """Check if the server will still be joined after the given events have
         been persised.
@@ -1137,11 +1112,6 @@ class EventsPersistenceStorageController:
             ev_ctx_rm
             delta: The delta of current state between what is in the database
                 and what the new current state will be.
-            current_state: The new current state if it already been calculated,
-                otherwise None.
-            potentially_left_users: If the server has left the room, then joined
-                remote users will be added to this set to indicate that the
-                server may no longer be sharing a room with them.
         """
 
         if not any(
@@ -1195,45 +1165,4 @@ class EventsPersistenceStorageController:
         ):
             return True
 
-        # The server will leave the room, so we go and find out which remote
-        # users will still be joined when we leave.
-        if current_state is None:
-            current_state = await self.main_store.get_partial_current_state_ids(room_id)
-            current_state = dict(current_state)
-            for key in delta.to_delete:
-                current_state.pop(key, None)
-
-            current_state.update(delta.to_insert)
-
-        remote_event_ids = [
-            event_id
-            for (
-                typ,
-                state_key,
-            ), event_id in current_state.items()
-            if typ == EventTypes.Member and not self.is_mine_id(state_key)
-        ]
-        members = await self.main_store.get_membership_from_event_ids(remote_event_ids)
-        potentially_left_users.update(
-            member.user_id
-            for member in members.values()
-            if member and member.membership == Membership.JOIN
-        )
-
         return False
-
-    async def _handle_potentially_left_users(self, user_ids: Set[str]) -> None:
-        """Given a set of remote users check if the server still shares a room with
-        them. If not then mark those users' device cache as stale.
-        """
-
-        if not user_ids:
-            return
-
-        joined_users = await self.main_store.get_users_server_still_shares_room_with(
-            user_ids
-        )
-        left_users = user_ids - joined_users
-
-        for user_id in left_users:
-            await self.main_store.mark_remote_user_device_list_as_unsubscribed(user_id)
-- 
cgit 1.4.1