1 files changed, 27 insertions, 1 deletions
diff --git a/synapse/synapse_rust/events.pyi b/synapse/synapse_rust/events.pyi
index 1682d0d151..7d3422572d 100644
--- a/synapse/synapse_rust/events.pyi
+++ b/synapse/synapse_rust/events.pyi
@@ -10,7 +10,7 @@
 # See the GNU Affero General Public License for more details:
 # <https://www.gnu.org/licenses/agpl-3.0.html>.
 
-from typing import Optional
+from typing import List, Mapping, Optional, Tuple
 
 from synapse.types import JsonDict
 
@@ -105,3 +105,29 @@ class EventInternalMetadata:
 
     def is_notifiable(self) -> bool:
         """Whether this event can trigger a push notification"""
+
+def event_visible_to_server(
+    sender: str,
+    target_server_name: str,
+    history_visibility: str,
+    erased_senders: Mapping[str, bool],
+    partial_state_invisible: bool,
+    memberships: List[Tuple[str, str]],
+) -> bool:
+    """Determine whether the server is allowed to see the unredacted event.
+
+    Args:
+        sender: The sender of the event.
+        target_server_name: The server we want to send the event to.
+        history_visibility: The history_visibility value at the event.
+        erased_senders: A mapping of users and whether they have requested erasure. If a
+            user is not in the map, it is treated as though they haven't requested erasure.
+        partial_state_invisible: Whether the event should be treated as invisible due to
+            the partial state status of the room.
+        memberships: A list of membership state information at the event for users
+            matching the `target_server_name`. Each list item must contain a tuple of
+            (state_key, membership).
+
+    Returns:
+        Whether the server is allowed to see the unredacted event.
+    """