2 files changed, 27 insertions, 6 deletions
diff --git a/synapse/replication/slave/storage/_base.py b/synapse/replication/slave/storage/_base.py
index 704282c800..f45cbd37a0 100644
--- a/synapse/replication/slave/storage/_base.py
+++ b/synapse/replication/slave/storage/_base.py
@@ -66,11 +66,16 @@ class BaseSlavedStore(SQLBaseStore):
                 self._cache_id_gen.advance(token)
             for row in rows:
                 if row.cache_func == CURRENT_STATE_CACHE_NAME:
+                    if row.keys is None:
+                        raise Exception(
+                            "Can't send an 'invalidate all' for current state cache"
+                        )
+
                     room_id = row.keys[0]
                     members_changed = set(row.keys[1:])
                     self._invalidate_state_caches(room_id, members_changed)
                 else:
-                    self._attempt_to_invalidate_cache(row.cache_func, tuple(row.keys))
+                    self._attempt_to_invalidate_cache(row.cache_func, row.keys)
 
     def _invalidate_cache_and_stream(self, txn, cache_func, keys):
         txn.call_after(cache_func.invalidate, keys)
diff --git a/synapse/replication/tcp/streams/_base.py b/synapse/replication/tcp/streams/_base.py
index e03e77199b..a8d568b14a 100644
--- a/synapse/replication/tcp/streams/_base.py
+++ b/synapse/replication/tcp/streams/_base.py
@@ -17,7 +17,9 @@
 import itertools
 import logging
 from collections import namedtuple
-from typing import Any
+from typing import Any, List, Optional
+
+import attr
 
 logger = logging.getLogger(__name__)
 
@@ -65,10 +67,24 @@ PushersStreamRow = namedtuple(
     "PushersStreamRow",
     ("user_id", "app_id", "pushkey", "deleted"),  # str  # str  # str  # bool
 )
-CachesStreamRow = namedtuple(
-    "CachesStreamRow",
-    ("cache_func", "keys", "invalidation_ts"),  # str  # list(str)  # int
-)
+
+
+@attr.s
+class CachesStreamRow:
+    """Stream to inform workers they should invalidate their cache.
+
+    Attributes:
+        cache_func: Name of the cached function.
+        keys: The entry in the cache to invalidate. If None then will
+            invalidate all.
+        invalidation_ts: Timestamp of when the invalidation took place.
+    """
+
+    cache_func = attr.ib(type=str)
+    keys = attr.ib(type=Optional[List[Any]])
+    invalidation_ts = attr.ib(type=int)
+
+
 PublicRoomsStreamRow = namedtuple(
     "PublicRoomsStreamRow",
     (