diff --git a/changelog.d/7980.bugfix b/changelog.d/7980.bugfix
new file mode 100644
index 0000000000..fa351b4b77
--- /dev/null
+++ b/changelog.d/7980.bugfix
@@ -0,0 +1 @@
+Fix "no create event in auth events" when trying to reject invitation after inviter leaves. Bug introduced in Synapse v1.10.0.
diff --git a/synapse/handlers/room_member.py b/synapse/handlers/room_member.py
index 5a40e8c144..78586a0a1e 100644
--- a/synapse/handlers/room_member.py
+++ b/synapse/handlers/room_member.py
@@ -469,26 +469,39 @@ class RoomMemberHandler(object):
user_id=target.to_string(), room_id=room_id
) # type: Optional[RoomsForUser]
if not invite:
+ logger.info(
+ "%s sent a leave request to %s, but that is not an active room "
+ "on this server, and there is no pending invite",
+ target,
+ room_id,
+ )
+
raise SynapseError(404, "Not a known room")
logger.info(
"%s rejects invite to %s from %s", target, room_id, invite.sender
)
- if self.hs.is_mine_id(invite.sender):
- # the inviter was on our server, but has now left. Carry on
- # with the normal rejection codepath.
- #
- # This is a bit of a hack, because the room might still be
- # active on other servers.
- pass
- else:
+ if not self.hs.is_mine_id(invite.sender):
# send the rejection to the inviter's HS (with fallback to
# local event)
return await self.remote_reject_invite(
invite.event_id, txn_id, requester, content,
)
+ # the inviter was on our server, but has now left. Carry on
+ # with the normal rejection codepath, which will also send the
+ # rejection out to any other servers we believe are still in the room.
+
+ # thanks to overzealous cleaning up of event_forward_extremities in
+ # `delete_old_current_state_events`, it's possible to end up with no
+ # forward extremities here. If that happens, let's just hang the
+ # rejection off the invite event.
+ #
+ # see: https://github.com/matrix-org/synapse/issues/7139
+ if len(latest_event_ids) == 0:
+ latest_event_ids = [invite.event_id]
+
return await self._local_membership_update(
requester=requester,
target=target,
|
