Wait for streams to catch up when processing HTTP replication. (#14820)

This should hopefully mitigate a class of races where data gets out of
sync due a HTTP replication request racing with the replication streams.

1 files changed, 1 insertions, 3 deletions

diff --git a/synapse/replication/http/send_events.py b/synapse/replication/http/send_events.py
index 8889bbb644..4f82c9f96d 100644
--- a/synapse/replication/http/send_events.py
+++ b/synapse/replication/http/send_events.py
@@ -21,7 +21,6 @@ from synapse.api.room_versions import KNOWN_ROOM_VERSIONS
 from synapse.events import EventBase, make_event_from_dict
 from synapse.events.snapshot import EventContext
 from synapse.http.server import HttpServer
-from synapse.http.servlet import parse_json_object_from_request
 from synapse.replication.http._base import ReplicationEndpoint
 from synapse.types import JsonDict, Requester, UserID
 from synapse.util.metrics import Measure
@@ -114,10 +113,9 @@ class ReplicationSendEventsRestServlet(ReplicationEndpoint):
         return payload
 
     async def _handle_request(  # type: ignore[override]
-        self, request: Request
+        self, request: Request, payload: JsonDict
     ) -> Tuple[int, JsonDict]:
         with Measure(self.clock, "repl_send_events_parse"):
-            payload = parse_json_object_from_request(request)
             events_and_context = []
             events = payload["events"]