diff options
Diffstat (limited to 'synapse/handlers/sync.py')
-rw-r--r-- | synapse/handlers/sync.py | 69 |
1 files changed, 51 insertions, 18 deletions
diff --git a/synapse/handlers/sync.py b/synapse/handlers/sync.py index ede014180c..6af2eeb75f 100644 --- a/synapse/handlers/sync.py +++ b/synapse/handlers/sync.py @@ -43,6 +43,7 @@ from prometheus_client import Counter from synapse.api.constants import ( AccountDataTypes, + Direction, EventContentFields, EventTypes, JoinRules, @@ -64,6 +65,7 @@ from synapse.logging.opentracing import ( ) from synapse.storage.databases.main.event_push_actions import RoomNotifCounts from synapse.storage.databases.main.roommember import extract_heroes_from_room_summary +from synapse.storage.databases.main.stream import PaginateFunction from synapse.storage.roommember import MemberSummary from synapse.types import ( DeviceListUpdates, @@ -879,22 +881,49 @@ class SyncHandler: since_key = since_token.room_key while limited and len(recents) < timeline_limit and max_repeat: - # If we have a since_key then we are trying to get any events - # that have happened since `since_key` up to `end_key`, so we - # can just use `get_room_events_stream_for_room`. - # Otherwise, we want to return the last N events in the room - # in topological ordering. - if since_key: - events, end_key = await self.store.get_room_events_stream_for_room( - room_id, - limit=load_limit + 1, - from_key=since_key, - to_key=end_key, - ) - else: - events, end_key = await self.store.get_recent_events_for_room( - room_id, limit=load_limit + 1, end_token=end_key - ) + # For initial `/sync`, we want to view a historical section of the + # timeline; to fetch events by `topological_ordering` (best + # representation of the room DAG as others were seeing it at the time). + # This also aligns with the order that `/messages` returns events in. + # + # For incremental `/sync`, we want to get all updates for rooms since + # the last `/sync` (regardless if those updates arrived late or happened + # a while ago in the past); to fetch events by `stream_ordering` (in the + # order they were received by the server). + # + # Relevant spec issue: https://github.com/matrix-org/matrix-spec/issues/1917 + # + # FIXME: Using workaround for mypy, + # https://github.com/python/mypy/issues/10740#issuecomment-1997047277 and + # https://github.com/python/mypy/issues/17479 + paginate_room_events_by_topological_ordering: PaginateFunction = ( + self.store.paginate_room_events_by_topological_ordering + ) + paginate_room_events_by_stream_ordering: PaginateFunction = ( + self.store.paginate_room_events_by_stream_ordering + ) + pagination_method: PaginateFunction = ( + # Use `topographical_ordering` for historical events + paginate_room_events_by_topological_ordering + if since_key is None + # Use `stream_ordering` for updates + else paginate_room_events_by_stream_ordering + ) + events, end_key = await pagination_method( + room_id=room_id, + # The bounds are reversed so we can paginate backwards + # (from newer to older events) starting at to_bound. + # This ensures we fill the `limit` with the newest events first, + from_key=end_key, + to_key=since_key, + direction=Direction.BACKWARDS, + # We add one so we can determine if there are enough events to saturate + # the limit or not (see `limited`) + limit=load_limit + 1, + ) + # We want to return the events in ascending order (the last event is the + # most recent). + events.reverse() log_kv({"loaded_recents": len(events)}) @@ -2641,9 +2670,10 @@ class SyncHandler: # a "gap" in the timeline, as described by the spec for /sync. room_to_events = await self.store.get_room_events_stream_for_rooms( room_ids=sync_result_builder.joined_room_ids, - from_key=since_token.room_key, - to_key=now_token.room_key, + from_key=now_token.room_key, + to_key=since_token.room_key, limit=timeline_limit + 1, + direction=Direction.BACKWARDS, ) # We loop through all room ids, even if there are no new events, in case @@ -2654,6 +2684,9 @@ class SyncHandler: newly_joined = room_id in newly_joined_rooms if room_entry: events, start_key = room_entry + # We want to return the events in ascending order (the last event is the + # most recent). + events.reverse() prev_batch_token = now_token.copy_and_replace( StreamKeyType.ROOM, start_key |