diff options
| -rw-r--r-- | changelog.d/11027.bugfix | 1 | ||||
| -rw-r--r-- | synapse/handlers/federation.py | 24 | ||||
| -rw-r--r-- | synapse/handlers/federation_event.py | 2 | ||||
| -rw-r--r-- | tests/handlers/test_federation.py | 64 |
4 files changed, 79 insertions, 12 deletions
diff --git a/changelog.d/11027.bugfix b/changelog.d/11027.bugfix new file mode 100644 index 0000000000..ae6cc44470 --- /dev/null +++ b/changelog.d/11027.bugfix @@ -0,0 +1 @@ +Fix 500 error on `/messages` when the server accumulates more than 5 backwards extremities at a given depth for a room. diff --git a/synapse/handlers/federation.py b/synapse/handlers/federation.py index 3e341bd287..e072efad16 100644 --- a/synapse/handlers/federation.py +++ b/synapse/handlers/federation.py @@ -238,18 +238,10 @@ class FederationHandler: ) return False - logger.debug( - "room_id: %s, backfill: current_depth: %s, max_depth: %s, extrems: %s", - room_id, - current_depth, - max_depth, - sorted_extremeties_tuple, - ) - # We ignore extremities that have a greater depth than our current depth # as: # 1. we don't really care about getting events that have happened - # before our current position; and + # after our current position; and # 2. we have likely previously tried and failed to backfill from that # extremity, so to avoid getting "stuck" requesting the same # backfill repeatedly we drop those extremities. @@ -257,9 +249,19 @@ class FederationHandler: t for t in sorted_extremeties_tuple if int(t[1]) <= current_depth ] + logger.debug( + "room_id: %s, backfill: current_depth: %s, limit: %s, max_depth: %s, extrems: %s filtered_sorted_extremeties_tuple: %s", + room_id, + current_depth, + limit, + max_depth, + sorted_extremeties_tuple, + filtered_sorted_extremeties_tuple, + ) + # However, we need to check that the filtered extremities are non-empty. # If they are empty then either we can a) bail or b) still attempt to - # backill. We opt to try backfilling anyway just in case we do get + # backfill. We opt to try backfilling anyway just in case we do get # relevant events. if filtered_sorted_extremeties_tuple: sorted_extremeties_tuple = filtered_sorted_extremeties_tuple @@ -389,7 +391,7 @@ class FederationHandler: for key, state_dict in states.items() } - for e_id, _ in sorted_extremeties_tuple: + for e_id in event_ids: likely_extremeties_domains = get_domains_from_state(states[e_id]) success = await try_backfill( diff --git a/synapse/handlers/federation_event.py b/synapse/handlers/federation_event.py index f640b417b3..0e455678aa 100644 --- a/synapse/handlers/federation_event.py +++ b/synapse/handlers/federation_event.py @@ -392,7 +392,7 @@ class FederationEventHandler: @log_function async def backfill( - self, dest: str, room_id: str, limit: int, extremities: List[str] + self, dest: str, room_id: str, limit: int, extremities: Iterable[str] ) -> None: """Trigger a backfill request to `dest` for the given `room_id` diff --git a/tests/handlers/test_federation.py b/tests/handlers/test_federation.py index 936ebf3dde..e1557566e4 100644 --- a/tests/handlers/test_federation.py +++ b/tests/handlers/test_federation.py @@ -23,6 +23,7 @@ from synapse.federation.federation_base import event_from_pdu_json from synapse.logging.context import LoggingContext, run_in_background from synapse.rest import admin from synapse.rest.client import login, room +from synapse.types import create_requester from synapse.util.stringutils import random_string from tests import unittest @@ -30,6 +31,10 @@ from tests import unittest logger = logging.getLogger(__name__) +def generate_fake_event_id() -> str: + return "$fake_" + random_string(43) + + class FederationTestCase(unittest.HomeserverTestCase): servlets = [ admin.register_servlets, @@ -198,6 +203,65 @@ class FederationTestCase(unittest.HomeserverTestCase): self.assertEqual(sg, sg2) + def test_backfill_with_many_backward_extremities(self): + """ + Check that we can backfill with many backward extremities. + The goal is to make sure that when we only use a portion + of backwards extremities(the magic number is more than 5), + no errors are thrown. + + Regression test, see #11027 + """ + # create the room + user_id = self.register_user("kermit", "test") + tok = self.login("kermit", "test") + requester = create_requester(user_id) + + room_id = self.helper.create_room_as(room_creator=user_id, tok=tok) + + ev1 = self.helper.send(room_id, "first message", tok=tok) + + # Create "many" backward extremities. The magic number we're trying to + # create more than is 5 which corresponds to the number of backward + # extremities we slice off in `_maybe_backfill_inner` + for _ in range(0, 8): + event_handler = self.hs.get_event_creation_handler() + event, context = self.get_success( + event_handler.create_event( + requester, + { + "type": "m.room.message", + "content": { + "msgtype": "m.text", + "body": "message connected to fake event", + }, + "room_id": room_id, + "sender": user_id, + }, + prev_event_ids=[ + ev1["event_id"], + # We're creating an backward extremity each time thanks + # to this fake event + generate_fake_event_id(), + ], + ) + ) + self.get_success( + event_handler.handle_new_client_event(requester, event, context) + ) + + current_depth = 1 + limit = 100 + with LoggingContext("receive_pdu"): + # Make sure backfill still works + d = run_in_background( + self.hs.get_federation_handler().maybe_backfill, + room_id, + current_depth, + limit, + ) + self.get_success(d) + def test_backfill_floating_outlier_membership_auth(self): """ As the local homeserver, check that we can properly process a federated |