From 3406333a58d9887cdb79ef73cae218c705ac11b0 Mon Sep 17 00:00:00 2001 From: Richard van der Hoff Date: Thu, 9 Mar 2017 12:20:46 +0000 Subject: Factor _get_missing_events_for_pdu out of _handle_new_pdu This should be functionally identical: it just seeks to improve readability by reducing indentation. --- synapse/federation/federation_server.py | 144 ++++++++++++++++++-------------- 1 file changed, 82 insertions(+), 62 deletions(-) (limited to 'synapse/federation') diff --git a/synapse/federation/federation_server.py b/synapse/federation/federation_server.py index e922b7ff4a..3ef700f7fc 100644 --- a/synapse/federation/federation_server.py +++ b/synapse/federation/federation_server.py @@ -574,68 +574,9 @@ class FederationServer(FederationBase): pdu.room_id, len(prevs - seen), ) - # We recalculate seen, since it may have changed. - have_seen = yield self.store.have_events(prevs) - seen = set(have_seen.keys()) - - if prevs - seen: - latest = yield self.store.get_latest_event_ids_in_room( - pdu.room_id - ) - - # We add the prev events that we have seen to the latest - # list to ensure the remote server doesn't give them to us - latest = set(latest) - latest |= seen - - logger.info( - "Missing %d events for room %r: %r...", - len(prevs - seen), pdu.room_id, list(prevs - seen)[:5] - ) - - # XXX: we set timeout to 10s to help workaround - # https://github.com/matrix-org/synapse/issues/1733. - # The reason is to avoid holding the linearizer lock - # whilst processing inbound /send transactions, causing - # FDs to stack up and block other inbound transactions - # which empirically can currently take up to 30 minutes. - # - # N.B. this explicitly disables retry attempts. - # - # N.B. this also increases our chances of falling back to - # fetching fresh state for the room if the missing event - # can't be found, which slightly reduces our security. - # it may also increase our DAG extremity count for the room, - # causing additional state resolution? See #1760. - # However, fetching state doesn't hold the linearizer lock - # apparently. - # - # see https://github.com/matrix-org/synapse/pull/1744 - - missing_events = yield self.get_missing_events( - origin, - pdu.room_id, - earliest_events_ids=list(latest), - latest_events=[pdu], - limit=10, - min_depth=min_depth, - timeout=10000, - ) - - # We want to sort these by depth so we process them and - # tell clients about them in order. - missing_events.sort(key=lambda x: x.depth) - - for e in missing_events: - yield self._handle_new_pdu( - origin, - e, - get_missing=False - ) - - have_seen = yield self.store.have_events( - [ev for ev, _ in pdu.prev_events] - ) + yield self._get_missing_events_for_pdu( + origin, pdu, prevs, min_depth + ) prevs = {e_id for e_id, _ in pdu.prev_events} seen = set(have_seen.keys()) @@ -667,6 +608,85 @@ class FederationServer(FederationBase): auth_chain=auth_chain, ) + @defer.inlineCallbacks + def _get_missing_events_for_pdu(self, origin, pdu, prevs, min_depth): + """ + Args: + origin (str): Origin of the pdu. Will be called to get the missing events + pdu: received pdu + prevs (str[]): List of event ids which we are missing + min_depth (int): Minimum depth of events to return. + + Returns: + Deferred: updated have_seen dictionary + """ + # We recalculate seen, since it may have changed. + have_seen = yield self.store.have_events(prevs) + seen = set(have_seen.keys()) + + if not prevs - seen: + # nothing left to do + defer.returnValue(have_seen) + + latest = yield self.store.get_latest_event_ids_in_room( + pdu.room_id + ) + + # We add the prev events that we have seen to the latest + # list to ensure the remote server doesn't give them to us + latest = set(latest) + latest |= seen + + logger.info( + "Missing %d events for room %r: %r...", + len(prevs - seen), pdu.room_id, list(prevs - seen)[:5] + ) + + # XXX: we set timeout to 10s to help workaround + # https://github.com/matrix-org/synapse/issues/1733. + # The reason is to avoid holding the linearizer lock + # whilst processing inbound /send transactions, causing + # FDs to stack up and block other inbound transactions + # which empirically can currently take up to 30 minutes. + # + # N.B. this explicitly disables retry attempts. + # + # N.B. this also increases our chances of falling back to + # fetching fresh state for the room if the missing event + # can't be found, which slightly reduces our security. + # it may also increase our DAG extremity count for the room, + # causing additional state resolution? See #1760. + # However, fetching state doesn't hold the linearizer lock + # apparently. + # + # see https://github.com/matrix-org/synapse/pull/1744 + + missing_events = yield self.get_missing_events( + origin, + pdu.room_id, + earliest_events_ids=list(latest), + latest_events=[pdu], + limit=10, + min_depth=min_depth, + timeout=10000, + ) + + # We want to sort these by depth so we process them and + # tell clients about them in order. + missing_events.sort(key=lambda x: x.depth) + + for e in missing_events: + yield self._handle_new_pdu( + origin, + e, + get_missing=False + ) + + have_seen = yield self.store.have_events( + [ev for ev, _ in pdu.prev_events] + ) + defer.returnValue(have_seen) + def __str__(self): return "" % self.server_name -- cgit 1.4.1