From cc7a294e2ec271126207922ea293e16d2a858943 Mon Sep 17 00:00:00 2001 From: Erik Johnston Date: Tue, 14 Mar 2017 10:54:28 +0000 Subject: [PATCH] Fix current_state_events table to not lie If we try and persist two state events that have the same ancestor we calculate the wrong current state when persisting those events. --- synapse/storage/events.py | 31 ++++++++++++++++++++++++++++--- 1 file changed, 28 insertions(+), 3 deletions(-) diff --git a/synapse/storage/events.py b/synapse/storage/events.py index db01eb6d1..03881ea3d 100644 --- a/synapse/storage/events.py +++ b/synapse/storage/events.py @@ -433,11 +433,36 @@ class EventsStore(SQLBaseStore): if not new_latest_event_ids: current_state = {} elif was_updated: + # We work out the current state by passing the state sets to the + # state resolution algorithm. It may ask for some events, including + # the events we have yet to persist, so we need a slightly more + # complicated event lookup function than simply looking the events + # up in the db. + events_map = {ev.event_id: ev for ev, _ in events_context} + + @defer.inlineCallbacks + def get_events(ev_ids): + # We get the events by first looking at the list of events we + # are trying to persist, and then fetching the rest from the DB. + db = [] + to_return = {} + for ev_id in ev_ids: + ev = events_map.get(ev_id, None) + if ev: + to_return[ev_id] = ev + else: + db.append(ev_id) + + if db: + evs = yield self.get_events( + ev_ids, get_prev_content=False, check_redacted=False, + ) + to_return.update(evs) + defer.returnValue(to_return) + current_state = yield resolve_events( state_sets, - state_map_factory=lambda ev_ids: self.get_events( - ev_ids, get_prev_content=False, check_redacted=False, - ), + state_map_factory=get_events, ) else: return