From 63d6ad1064c1a5fe23da3b6b64474a2b211f5eea Mon Sep 17 00:00:00 2001 From: Richard van der Hoff <1389908+richvdh@users.noreply.github.com> Date: Thu, 5 Dec 2019 15:02:35 +0000 Subject: [PATCH] Stronger typing in the federation handler (#6480) replace the event_info dict with an attrs thing --- changelog.d/6480.misc | 1 + synapse/handlers/federation.py | 81 ++++++++++++++++++++++++---------- 2 files changed, 58 insertions(+), 24 deletions(-) create mode 100644 changelog.d/6480.misc diff --git a/changelog.d/6480.misc b/changelog.d/6480.misc new file mode 100644 index 000000000..d9a44389b --- /dev/null +++ b/changelog.d/6480.misc @@ -0,0 +1 @@ +Refactor some code in the event authentication path for clarity. diff --git a/synapse/handlers/federation.py b/synapse/handlers/federation.py index f5d04cdf9..bc2692176 100644 --- a/synapse/handlers/federation.py +++ b/synapse/handlers/federation.py @@ -19,11 +19,13 @@ import itertools import logging +from typing import Dict, Iterable, Optional, Sequence, Tuple import six from six import iteritems, itervalues from six.moves import http_client, zip +import attr from signedjson.key import decode_verify_key_bytes from signedjson.sign import verify_signed_json from unpaddedbase64 import decode_base64 @@ -45,6 +47,7 @@ from synapse.api.errors import ( from synapse.api.room_versions import KNOWN_ROOM_VERSIONS, RoomVersions from synapse.crypto.event_signing import compute_event_signature from synapse.event_auth import auth_types_for_event +from synapse.events import EventBase from synapse.events.snapshot import EventContext from synapse.events.validator import EventValidator from synapse.logging.context import ( @@ -72,6 +75,23 @@ from ._base import BaseHandler logger = logging.getLogger(__name__) +@attr.s +class _NewEventInfo: + """Holds information about a received event, ready for passing to _handle_new_events + + Attributes: + event: the received event + + state: the state at that event + + auth_events: the auth_event map for that event + """ + + event = attr.ib(type=EventBase) + state = attr.ib(type=Optional[Sequence[EventBase]], default=None) + auth_events = attr.ib(type=Optional[Dict[Tuple[str, str], EventBase]], default=None) + + def shortstr(iterable, maxitems=5): """If iterable has maxitems or fewer, return the stringification of a list containing those items. @@ -597,14 +617,14 @@ class FederationHandler(BaseHandler): for e in auth_chain if e.event_id in auth_ids or e.type == EventTypes.Create } - event_infos.append({"event": e, "auth_events": auth}) + event_infos.append(_NewEventInfo(event=e, auth_events=auth)) seen_ids.add(e.event_id) logger.info( "[%s %s] persisting newly-received auth/state events %s", room_id, event_id, - [e["event"].event_id for e in event_infos], + [e.event.event_id for e in event_infos], ) yield self._handle_new_events(origin, event_infos) @@ -795,9 +815,9 @@ class FederationHandler(BaseHandler): a.internal_metadata.outlier = True ev_infos.append( - { - "event": a, - "auth_events": { + _NewEventInfo( + event=a, + auth_events={ ( auth_events[a_id].type, auth_events[a_id].state_key, @@ -805,7 +825,7 @@ class FederationHandler(BaseHandler): for a_id in a.auth_event_ids() if a_id in auth_events }, - } + ) ) # Step 1b: persist the events in the chunk we fetched state for (i.e. @@ -817,10 +837,10 @@ class FederationHandler(BaseHandler): assert not ev.internal_metadata.is_outlier() ev_infos.append( - { - "event": ev, - "state": events_to_state[e_id], - "auth_events": { + _NewEventInfo( + event=ev, + state=events_to_state[e_id], + auth_events={ ( auth_events[a_id].type, auth_events[a_id].state_key, @@ -828,7 +848,7 @@ class FederationHandler(BaseHandler): for a_id in ev.auth_event_ids() if a_id in auth_events }, - } + ) ) yield self._handle_new_events(dest, ev_infos, backfilled=True) @@ -1713,7 +1733,12 @@ class FederationHandler(BaseHandler): return context @defer.inlineCallbacks - def _handle_new_events(self, origin, event_infos, backfilled=False): + def _handle_new_events( + self, + origin: str, + event_infos: Iterable[_NewEventInfo], + backfilled: bool = False, + ): """Creates the appropriate contexts and persists events. The events should not depend on one another, e.g. this should be used to persist a bunch of outliers, but not a chunk of individual events that depend @@ -1723,14 +1748,14 @@ class FederationHandler(BaseHandler): """ @defer.inlineCallbacks - def prep(ev_info): - event = ev_info["event"] + def prep(ev_info: _NewEventInfo): + event = ev_info.event with nested_logging_context(suffix=event.event_id): res = yield self._prep_event( origin, event, - state=ev_info.get("state"), - auth_events=ev_info.get("auth_events"), + state=ev_info.state, + auth_events=ev_info.auth_events, backfilled=backfilled, ) return res @@ -1744,7 +1769,7 @@ class FederationHandler(BaseHandler): yield self.persist_events_and_notify( [ - (ev_info["event"], context) + (ev_info.event, context) for ev_info, context in zip(event_infos, contexts) ], backfilled=backfilled, @@ -1846,7 +1871,14 @@ class FederationHandler(BaseHandler): yield self.persist_events_and_notify([(event, new_event_context)]) @defer.inlineCallbacks - def _prep_event(self, origin, event, state, auth_events, backfilled): + def _prep_event( + self, + origin: str, + event: EventBase, + state: Optional[Iterable[EventBase]], + auth_events: Optional[Dict[Tuple[str, str], EventBase]], + backfilled: bool, + ): """ Args: @@ -1854,7 +1886,7 @@ class FederationHandler(BaseHandler): event: state: auth_events: - backfilled (bool) + backfilled: Returns: Deferred, which resolves to synapse.events.snapshot.EventContext @@ -1890,15 +1922,16 @@ class FederationHandler(BaseHandler): return context @defer.inlineCallbacks - def _check_for_soft_fail(self, event, state, backfilled): + def _check_for_soft_fail( + self, event: EventBase, state: Optional[Iterable[EventBase]], backfilled: bool + ): """Checks if we should soft fail the event, if so marks the event as such. Args: - event (FrozenEvent) - state (dict|None): The state at the event if we don't have all the - event's prev events - backfilled (bool): Whether the event is from backfill + event + state: The state at the event if we don't have all the event's prev events + backfilled: Whether the event is from backfill Returns: Deferred