diff --git a/synapse/storage/databases/main/stream.py b/synapse/storage/databases/main/stream.py
index 42dc807d17..57aab55259 100644
--- a/synapse/storage/databases/main/stream.py
+++ b/synapse/storage/databases/main/stream.py
@@ -497,7 +497,7 @@ class StreamWorkerStore(EventsWorkerStore, SQLBaseStore, metaclass=abc.ABCMeta):
oldest `limit` events.
Returns:
- The list of events (in ascending order) and the token from the start
+ The list of events (in ascending stream order) and the token from the start
of the chunk of events returned.
"""
if from_key == to_key:
@@ -510,7 +510,7 @@ class StreamWorkerStore(EventsWorkerStore, SQLBaseStore, metaclass=abc.ABCMeta):
if not has_changed:
return [], from_key
- def f(txn):
+ def f(txn: LoggingTransaction) -> List[_EventDictReturn]:
# To handle tokens with a non-empty instance_map we fetch more
# results than necessary and then filter down
min_from_id = from_key.stream
@@ -565,6 +565,13 @@ class StreamWorkerStore(EventsWorkerStore, SQLBaseStore, metaclass=abc.ABCMeta):
async def get_membership_changes_for_user(
self, user_id: str, from_key: RoomStreamToken, to_key: RoomStreamToken
) -> List[EventBase]:
+ """Fetch membership events for a given user.
+
+ All such events whose stream ordering `s` lies in the range
+ `from_key < s <= to_key` are returned. Events are ordered by ascending stream
+ order.
+ """
+ # Start by ruling out cases where a DB query is not necessary.
if from_key == to_key:
return []
@@ -575,7 +582,7 @@ class StreamWorkerStore(EventsWorkerStore, SQLBaseStore, metaclass=abc.ABCMeta):
if not has_changed:
return []
- def f(txn):
+ def f(txn: LoggingTransaction) -> List[_EventDictReturn]:
# To handle tokens with a non-empty instance_map we fetch more
# results than necessary and then filter down
min_from_id = from_key.stream
@@ -634,7 +641,7 @@ class StreamWorkerStore(EventsWorkerStore, SQLBaseStore, metaclass=abc.ABCMeta):
Returns:
A list of events and a token pointing to the start of the returned
- events. The events returned are in ascending order.
+ events. The events returned are in ascending topological order.
"""
rows, token = await self.get_recent_event_ids_for_room(
|
