diff options
Diffstat (limited to 'synapse/handlers/message.py')
| -rw-r--r-- | synapse/handlers/message.py | 24 |
1 files changed, 18 insertions, 6 deletions
diff --git a/synapse/handlers/message.py b/synapse/handlers/message.py index 87f671708c..38409fef38 100644 --- a/synapse/handlers/message.py +++ b/synapse/handlers/message.py @@ -496,6 +496,7 @@ class EventCreationHandler: require_consent: bool = True, outlier: bool = False, historical: bool = False, + allow_no_prev_events: bool = False, depth: Optional[int] = None, ) -> Tuple[EventBase, EventContext]: """ @@ -607,6 +608,7 @@ class EventCreationHandler: prev_event_ids=prev_event_ids, auth_event_ids=auth_event_ids, depth=depth, + allow_no_prev_events=allow_no_prev_events, ) # In an ideal world we wouldn't need the second part of this condition. However, @@ -882,6 +884,7 @@ class EventCreationHandler: prev_event_ids: Optional[List[str]] = None, auth_event_ids: Optional[List[str]] = None, depth: Optional[int] = None, + allow_no_prev_events: bool = False, ) -> Tuple[EventBase, EventContext]: """Create a new event for a local client @@ -912,6 +915,7 @@ class EventCreationHandler: full_state_ids_at_event = None if auth_event_ids is not None: # If auth events are provided, prev events must be also. + # prev_event_ids could be an empty array though. assert prev_event_ids is not None # Copy the full auth state before it stripped down @@ -943,14 +947,22 @@ class EventCreationHandler: else: prev_event_ids = await self.store.get_prev_events_for_room(builder.room_id) - # we now ought to have some prev_events (unless it's a create event). - # - # do a quick sanity check here, rather than waiting until we've created the + # Do a quick sanity check here, rather than waiting until we've created the # event and then try to auth it (which fails with a somewhat confusing "No # create event in auth events") - assert ( - builder.type == EventTypes.Create or len(prev_event_ids) > 0 - ), "Attempting to create an event with no prev_events" + if allow_no_prev_events: + # We allow events with no `prev_events` but it better have some `auth_events` + assert ( + builder.type == EventTypes.Create + # Allow an event to have empty list of prev_event_ids + # only if it has auth_event_ids. + or auth_event_ids + ), "Attempting to create a non-m.room.create event with no prev_events or auth_event_ids" + else: + # we now ought to have some prev_events (unless it's a create event). + assert ( + builder.type == EventTypes.Create or prev_event_ids + ), "Attempting to create a non-m.room.create event with no prev_events" event = await builder.build( prev_event_ids=prev_event_ids, |