diff options
| -rw-r--r-- | synapse/util/caches/deferred_cache.py | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/synapse/util/caches/deferred_cache.py b/synapse/util/caches/deferred_cache.py index fc01026285..601305487c 100644 --- a/synapse/util/caches/deferred_cache.py +++ b/synapse/util/caches/deferred_cache.py @@ -31,6 +31,7 @@ from typing import ( from prometheus_client import Gauge from twisted.internet import defer +from twisted.python import failure from synapse.util.async_helpers import ObservableDeferred from synapse.util.caches.lrucache import LruCache @@ -223,7 +224,9 @@ class DeferredCache(Generic[KT, VT]): # we can save a whole load of effort if the deferred is ready. if value.called: - self.cache.set(key, value.result, callbacks) + result = value.result + if not isinstance(result, failure.Failure): + self.cache.set(key, result, callbacks) return value # otherwise, we'll add an entry to the _pending_deferred_cache for now, |