Improve exception handling in persist_event

1. use `deferred.errback()` instead of `deferred.errback(e)`, which means that
a Failure object will be constructed using the current exception state,
*including* its stack trace - so the stack trace is saved in the Failure,
leading to better exception reports.

2. Set `consumeErrors=True` on the ObservableDeferred, because we know that
there will always be at least one observer - which avoids a spurious "CRITICAL:
unhandled exception in Deferred" error in the logs
This commit is contained in:
Richard van der Hoff 2018-01-27 14:00:11 +00:00
parent 4c65b98e4a
commit b387ee17b6

View file

@ -110,7 +110,7 @@ class _EventPeristenceQueue(object):
end_item.events_and_contexts.extend(events_and_contexts)
return end_item.deferred.observe()
deferred = ObservableDeferred(defer.Deferred())
deferred = ObservableDeferred(defer.Deferred(), consumeErrors=True)
queue.append(self._EventPersistQueueItem(
events_and_contexts=events_and_contexts,
@ -152,8 +152,8 @@ class _EventPeristenceQueue(object):
try:
ret = yield per_item_callback(item)
item.deferred.callback(ret)
except Exception as e:
item.deferred.errback(e)
except Exception:
item.deferred.errback()
finally:
queue = self._event_persist_queues.pop(room_id, None)
if queue: