diff --git a/synapse/util/caches/descriptors.py b/synapse/util/caches/descriptors.py
index ac4a078b26..2ac24a2f25 100644
--- a/synapse/util/caches/descriptors.py
+++ b/synapse/util/caches/descriptors.py
@@ -270,7 +270,6 @@ class DeferredCacheDescriptor(_CacheDescriptorBase):
cache = DeferredCache(
name=self.orig.__name__,
max_entries=self.max_entries,
- keylen=self.num_args,
tree=self.tree,
iterable=self.iterable,
) # type: DeferredCache[CacheKey, Any]
@@ -322,8 +321,8 @@ class DeferredCacheDescriptor(_CacheDescriptorBase):
class DeferredCacheListDescriptor(_CacheDescriptorBase):
"""Wraps an existing cache to support bulk fetching of keys.
- Given a list of keys it looks in the cache to find any hits, then passes
- the list of missing keys to the wrapped function.
+ Given an iterable of keys it looks in the cache to find any hits, then passes
+ the tuple of missing keys to the wrapped function.
Once wrapped, the function returns a Deferred which resolves to the list
of results.
@@ -437,7 +436,9 @@ class DeferredCacheListDescriptor(_CacheDescriptorBase):
return f
args_to_call = dict(arg_dict)
- args_to_call[self.list_name] = list(missing)
+ # copy the missing set before sending it to the callee, to guard against
+ # modification.
+ args_to_call[self.list_name] = tuple(missing)
cached_defers.append(
defer.maybeDeferred(
@@ -522,14 +523,14 @@ def cachedList(
Used to do batch lookups for an already created cache. A single argument
is specified as a list that is iterated through to lookup keys in the
- original cache. A new list consisting of the keys that weren't in the cache
- get passed to the original function, the result of which is stored in the
+ original cache. A new tuple consisting of the (deduplicated) keys that weren't in
+ the cache gets passed to the original function, the result of which is stored in the
cache.
Args:
cached_method_name: The name of the single-item lookup method.
This is only used to find the cache to use.
- list_name: The name of the argument that is the list to use to
+ list_name: The name of the argument that is the iterable to use to
do batch lookups in the cache.
num_args: Number of arguments to use as the key in the cache
(including list_name). Defaults to all named parameters.
|
