diff options
| -rw-r--r-- | changelog.d/14161.bugfix | 1 | ||||
| -rw-r--r-- | synapse/storage/databases/main/events_worker.py | 31 | ||||
| -rw-r--r-- | tests/storage/databases/main/test_events_worker.py | 12 |
3 files changed, 14 insertions, 30 deletions
diff --git a/changelog.d/14161.bugfix b/changelog.d/14161.bugfix new file mode 100644 index 0000000000..aed4d9e386 --- /dev/null +++ b/changelog.d/14161.bugfix @@ -0,0 +1 @@ +Fix a bug introduced in 1.30.0 where purging and rejoining a room without restarting in-between would result in a broken room. \ No newline at end of file diff --git a/synapse/storage/databases/main/events_worker.py b/synapse/storage/databases/main/events_worker.py index d4104462b5..cfd4780add 100644 --- a/synapse/storage/databases/main/events_worker.py +++ b/synapse/storage/databases/main/events_worker.py @@ -1502,21 +1502,15 @@ class EventsWorkerStore(SQLBaseStore): Returns: a dict {event_id -> bool} """ - # if the event cache contains the event, obviously we've seen it. - - cache_results = { - event_id - for event_id in event_ids - if await self._get_event_cache.contains((event_id,)) - } - results = dict.fromkeys(cache_results, True) - remaining = [ - event_id for event_id in event_ids if event_id not in cache_results - ] - if not remaining: - return results + # TODO: We used to query the _get_event_cache here as a fast-path before + # hitting the database. For if an event were in the cache, we've presumably + # seen it before. + # + # But this is currently an invalid assumption due to the _get_event_cache + # not being invalidated when purging events from a room. The optimisation can + # be re-added after https://github.com/matrix-org/synapse/issues/13476 - def have_seen_events_txn(txn: LoggingTransaction) -> None: + def have_seen_events_txn(txn: LoggingTransaction) -> Dict[str, bool]: # we deliberately do *not* query the database for room_id, to make the # query an index-only lookup on `events_event_id_key`. # @@ -1524,16 +1518,17 @@ class EventsWorkerStore(SQLBaseStore): sql = "SELECT event_id FROM events AS e WHERE " clause, args = make_in_list_sql_clause( - txn.database_engine, "e.event_id", remaining + txn.database_engine, "e.event_id", event_ids ) txn.execute(sql + clause, args) found_events = {eid for eid, in txn} # ... and then we can update the results for each key - results.update({eid: (eid in found_events) for eid in remaining}) + return {eid: (eid in found_events) for eid in event_ids} - await self.db_pool.runInteraction("have_seen_events", have_seen_events_txn) - return results + return await self.db_pool.runInteraction( + "have_seen_events", have_seen_events_txn + ) @cached(max_entries=100000, tree=True) async def have_seen_event(self, room_id: str, event_id: str) -> bool: diff --git a/tests/storage/databases/main/test_events_worker.py b/tests/storage/databases/main/test_events_worker.py index 32a798d74b..5773172ab8 100644 --- a/tests/storage/databases/main/test_events_worker.py +++ b/tests/storage/databases/main/test_events_worker.py @@ -90,18 +90,6 @@ class HaveSeenEventsTestCase(unittest.HomeserverTestCase): self.assertEqual(res, {self.event_ids[0]}) self.assertEqual(ctx.get_resource_usage().db_txn_count, 0) - def test_query_via_event_cache(self): - # fetch an event into the event cache - self.get_success(self.store.get_event(self.event_ids[0])) - - # looking it up should now cause no db hits - with LoggingContext(name="test") as ctx: - res = self.get_success( - self.store.have_seen_events(self.room_id, [self.event_ids[0]]) - ) - self.assertEqual(res, {self.event_ids[0]}) - self.assertEqual(ctx.get_resource_usage().db_txn_count, 0) - def test_persisting_event_invalidates_cache(self): """ Test to make sure that the `have_seen_event` cache |