From 25e55d25980ae048bd33f8c695a22a3ddaa971fe Mon Sep 17 00:00:00 2001 From: Patrick Cloke Date: Tue, 18 Aug 2020 07:53:23 -0400 Subject: Return the previous stream token if a non-member event is a duplicate. (#8093) --- changelog.d/8093.bugfix | 1 + synapse/handlers/message.py | 25 +++++++++++++++---------- 2 files changed, 16 insertions(+), 10 deletions(-) create mode 100644 changelog.d/8093.bugfix diff --git a/changelog.d/8093.bugfix b/changelog.d/8093.bugfix new file mode 100644 index 0000000000..80045dde1a --- /dev/null +++ b/changelog.d/8093.bugfix @@ -0,0 +1 @@ +Return the previous stream token if a non-member event is a duplicate. diff --git a/synapse/handlers/message.py b/synapse/handlers/message.py index 48b0fc7279..f242d3c6ac 100644 --- a/synapse/handlers/message.py +++ b/synapse/handlers/message.py @@ -667,14 +667,14 @@ class EventCreationHandler(object): assert self.hs.is_mine(user), "User must be our own: %s" % (user,) if event.is_state(): - prev_state = await self.deduplicate_state_event(event, context) - if prev_state is not None: + prev_event = await self.deduplicate_state_event(event, context) + if prev_event is not None: logger.info( "Not bothering to persist state event %s duplicated by %s", event.event_id, - prev_state.event_id, + prev_event.event_id, ) - return prev_state + return await self.store.get_stream_token_for_event(prev_event.event_id) return await self.handle_new_client_event( requester=requester, event=event, context=context, ratelimit=ratelimit @@ -682,27 +682,32 @@ class EventCreationHandler(object): async def deduplicate_state_event( self, event: EventBase, context: EventContext - ) -> None: + ) -> Optional[EventBase]: """ Checks whether event is in the latest resolved state in context. - If so, returns the version of the event in context. - Otherwise, returns None. + Args: + event: The event to check for duplication. + context: The event context. + + Returns: + The previous verion of the event is returned, if it is found in the + event context. Otherwise, None is returned. """ prev_state_ids = await context.get_prev_state_ids() prev_event_id = prev_state_ids.get((event.type, event.state_key)) if not prev_event_id: - return + return None prev_event = await self.store.get_event(prev_event_id, allow_none=True) if not prev_event: - return + return None if prev_event and event.user_id == prev_event.user_id: prev_content = encode_canonical_json(prev_event.content) next_content = encode_canonical_json(event.content) if prev_content == next_content: return prev_event - return + return None async def create_and_send_nonmember_event( self, -- cgit 1.4.1