diff options
Diffstat (limited to 'synapse/federation/federation_server.py')
| -rw-r--r-- | synapse/federation/federation_server.py | 98 |
1 files changed, 96 insertions, 2 deletions
diff --git a/synapse/federation/federation_server.py b/synapse/federation/federation_server.py index 2b07f18529..1d050e54e2 100644 --- a/synapse/federation/federation_server.py +++ b/synapse/federation/federation_server.py @@ -44,7 +44,7 @@ from synapse.api.errors import ( SynapseError, UnsupportedRoomVersionError, ) -from synapse.api.room_versions import KNOWN_ROOM_VERSIONS +from synapse.api.room_versions import KNOWN_ROOM_VERSIONS, RoomVersion from synapse.events import EventBase from synapse.federation.federation_base import FederationBase, event_from_pdu_json from synapse.federation.persistence import TransactionActions @@ -57,10 +57,12 @@ from synapse.logging.context import ( ) from synapse.logging.opentracing import log_kv, start_active_span_from_edu, trace from synapse.logging.utils import log_function +from synapse.metrics.background_process_metrics import wrap_as_background_process from synapse.replication.http.federation import ( ReplicationFederationSendEduRestServlet, ReplicationGetQueryRestServlet, ) +from synapse.storage.databases.main.lock import Lock from synapse.types import JsonDict from synapse.util import glob_to_regex, json_decoder, unwrapFirstError from synapse.util.async_helpers import Linearizer, concurrently_execute @@ -96,6 +98,11 @@ last_pdu_ts_metric = Gauge( ) +# The name of the lock to use when process events in a room received over +# federation. +_INBOUND_EVENT_HANDLING_LOCK_NAME = "federation_inbound_pdu" + + class FederationServer(FederationBase): def __init__(self, hs: "HomeServer"): super().__init__(hs) @@ -834,7 +841,94 @@ class FederationServer(FederationBase): except SynapseError as e: raise FederationError("ERROR", e.code, e.msg, affected=pdu.event_id) - await self.handler.on_receive_pdu(origin, pdu, sent_to_us_directly=True) + # Add the event to our staging area + await self.store.insert_received_event_to_staging(origin, pdu) + + # Try and acquire the processing lock for the room, if we get it start a + # background process for handling the events in the room. + lock = await self.store.try_acquire_lock( + _INBOUND_EVENT_HANDLING_LOCK_NAME, pdu.room_id + ) + if lock: + self._process_incoming_pdus_in_room_inner( + pdu.room_id, room_version, lock, origin, pdu + ) + + @wrap_as_background_process("_process_incoming_pdus_in_room_inner") + async def _process_incoming_pdus_in_room_inner( + self, + room_id: str, + room_version: RoomVersion, + lock: Lock, + latest_origin: str, + latest_event: EventBase, + ) -> None: + """Process events in the staging area for the given room. + + The latest_origin and latest_event args are the latest origin and event + received. + """ + + # The common path is for the event we just received be the only event in + # the room, so instead of pulling the event out of the DB and parsing + # the event we just pull out the next event ID and check if that matches. + next_origin, next_event_id = await self.store.get_next_staged_event_id_for_room( + room_id + ) + if next_origin == latest_origin and next_event_id == latest_event.event_id: + origin = latest_origin + event = latest_event + else: + next = await self.store.get_next_staged_event_for_room( + room_id, room_version + ) + if not next: + return + + origin, event = next + + # We loop round until there are no more events in the room in the + # staging area, or we fail to get the lock (which means another process + # has started processing). + while True: + async with lock: + try: + await self.handler.on_receive_pdu( + origin, event, sent_to_us_directly=True + ) + except FederationError as e: + # XXX: Ideally we'd inform the remote we failed to process + # the event, but we can't return an error in the transaction + # response (as we've already responded). + logger.warning("Error handling PDU %s: %s", event.event_id, e) + except Exception: + f = failure.Failure() + logger.error( + "Failed to handle PDU %s", + event.event_id, + exc_info=(f.type, f.value, f.getTracebackObject()), # type: ignore + ) + + await self.store.remove_received_event_from_staging( + origin, event.event_id + ) + + # We need to do this check outside the lock to avoid a race between + # a new event being inserted by another instance and it attempting + # to acquire the lock. + next = await self.store.get_next_staged_event_for_room( + room_id, room_version + ) + if not next: + break + + origin, event = next + + lock = await self.store.try_acquire_lock( + _INBOUND_EVENT_HANDLING_LOCK_NAME, room_id + ) + if not lock: + return def __str__(self) -> str: return "<ReplicationLayer(%s)>" % self.server_name |