mirror of
https://git.anonymousland.org/anonymousland/synapse-product.git
synced 2024-12-17 09:04:20 -05:00
Update get_pdu
to return the original, pristine EventBase
(#13320)
Update `get_pdu` to return the untouched, pristine `EventBase` as it was originally seen over federation (no metadata added). Previously, we returned the same `event` reference that we stored in the cache which downstream code modified in place and added metadata like setting it as an `outlier` and essentially poisoned our cache. Now we always return a copy of the `event` so the original can stay pristine in our cache and re-used for the next cache call.
Split out from https://github.com/matrix-org/synapse/pull/13205
As discussed at:
- https://github.com/matrix-org/synapse/pull/13205#discussion_r918365746
- https://github.com/matrix-org/synapse/pull/13205#discussion_r918366125
Related to https://github.com/matrix-org/synapse/issues/12584. This PR doesn't fix that issue because it hits [`get_event` which exists from the local database before it tries to `get_pdu`](7864f33e28/synapse/federation/federation_client.py (L581-L594)
).
This commit is contained in:
parent
a1b62af2af
commit
0f971ca68e
1
changelog.d/13320.misc
Normal file
1
changelog.d/13320.misc
Normal file
@ -0,0 +1 @@
|
||||
Fix `FederationClient.get_pdu()` returning events from the cache as `outliers` instead of original events we saw over federation.
|
@ -53,7 +53,7 @@ from synapse.api.room_versions import (
|
||||
RoomVersion,
|
||||
RoomVersions,
|
||||
)
|
||||
from synapse.events import EventBase, builder
|
||||
from synapse.events import EventBase, builder, make_event_from_dict
|
||||
from synapse.federation.federation_base import (
|
||||
FederationBase,
|
||||
InvalidEventSignatureError,
|
||||
@ -299,7 +299,8 @@ class FederationClient(FederationBase):
|
||||
moving to the next destination. None indicates no timeout.
|
||||
|
||||
Returns:
|
||||
The requested PDU, or None if we were unable to find it.
|
||||
A copy of the requested PDU that is safe to modify, or None if we
|
||||
were unable to find it.
|
||||
|
||||
Raises:
|
||||
SynapseError, NotRetryingDestination, FederationDeniedError
|
||||
@ -309,7 +310,7 @@ class FederationClient(FederationBase):
|
||||
)
|
||||
|
||||
logger.debug(
|
||||
"retrieved event id %s from %s: %r",
|
||||
"get_pdu_from_destination_raw: retrieved event id %s from %s: %r",
|
||||
event_id,
|
||||
destination,
|
||||
transaction_data,
|
||||
@ -358,54 +359,92 @@ class FederationClient(FederationBase):
|
||||
The requested PDU, or None if we were unable to find it.
|
||||
"""
|
||||
|
||||
logger.debug(
|
||||
"get_pdu: event_id=%s from destinations=%s", event_id, destinations
|
||||
)
|
||||
|
||||
# TODO: Rate limit the number of times we try and get the same event.
|
||||
|
||||
ev = self._get_pdu_cache.get(event_id)
|
||||
if ev:
|
||||
return ev
|
||||
# We might need the same event multiple times in quick succession (before
|
||||
# it gets persisted to the database), so we cache the results of the lookup.
|
||||
# Note that this is separate to the regular get_event cache which caches
|
||||
# events once they have been persisted.
|
||||
event = self._get_pdu_cache.get(event_id)
|
||||
|
||||
pdu_attempts = self.pdu_destination_tried.setdefault(event_id, {})
|
||||
# If we don't see the event in the cache, go try to fetch it from the
|
||||
# provided remote federated destinations
|
||||
if not event:
|
||||
pdu_attempts = self.pdu_destination_tried.setdefault(event_id, {})
|
||||
|
||||
signed_pdu = None
|
||||
for destination in destinations:
|
||||
now = self._clock.time_msec()
|
||||
last_attempt = pdu_attempts.get(destination, 0)
|
||||
if last_attempt + PDU_RETRY_TIME_MS > now:
|
||||
continue
|
||||
for destination in destinations:
|
||||
now = self._clock.time_msec()
|
||||
last_attempt = pdu_attempts.get(destination, 0)
|
||||
if last_attempt + PDU_RETRY_TIME_MS > now:
|
||||
logger.debug(
|
||||
"get_pdu: skipping destination=%s because we tried it recently last_attempt=%s and we only check every %s (now=%s)",
|
||||
destination,
|
||||
last_attempt,
|
||||
PDU_RETRY_TIME_MS,
|
||||
now,
|
||||
)
|
||||
continue
|
||||
|
||||
try:
|
||||
signed_pdu = await self.get_pdu_from_destination_raw(
|
||||
destination=destination,
|
||||
event_id=event_id,
|
||||
room_version=room_version,
|
||||
timeout=timeout,
|
||||
)
|
||||
try:
|
||||
event = await self.get_pdu_from_destination_raw(
|
||||
destination=destination,
|
||||
event_id=event_id,
|
||||
room_version=room_version,
|
||||
timeout=timeout,
|
||||
)
|
||||
|
||||
pdu_attempts[destination] = now
|
||||
pdu_attempts[destination] = now
|
||||
|
||||
except SynapseError as e:
|
||||
logger.info(
|
||||
"Failed to get PDU %s from %s because %s", event_id, destination, e
|
||||
)
|
||||
continue
|
||||
except NotRetryingDestination as e:
|
||||
logger.info(str(e))
|
||||
continue
|
||||
except FederationDeniedError as e:
|
||||
logger.info(str(e))
|
||||
continue
|
||||
except Exception as e:
|
||||
pdu_attempts[destination] = now
|
||||
if event:
|
||||
# Prime the cache
|
||||
self._get_pdu_cache[event.event_id] = event
|
||||
|
||||
logger.info(
|
||||
"Failed to get PDU %s from %s because %s", event_id, destination, e
|
||||
)
|
||||
continue
|
||||
# FIXME: We should add a `break` here to avoid calling every
|
||||
# destination after we already found a PDU (will follow-up
|
||||
# in a separate PR)
|
||||
|
||||
if signed_pdu:
|
||||
self._get_pdu_cache[event_id] = signed_pdu
|
||||
except SynapseError as e:
|
||||
logger.info(
|
||||
"Failed to get PDU %s from %s because %s",
|
||||
event_id,
|
||||
destination,
|
||||
e,
|
||||
)
|
||||
continue
|
||||
except NotRetryingDestination as e:
|
||||
logger.info(str(e))
|
||||
continue
|
||||
except FederationDeniedError as e:
|
||||
logger.info(str(e))
|
||||
continue
|
||||
except Exception as e:
|
||||
pdu_attempts[destination] = now
|
||||
|
||||
return signed_pdu
|
||||
logger.info(
|
||||
"Failed to get PDU %s from %s because %s",
|
||||
event_id,
|
||||
destination,
|
||||
e,
|
||||
)
|
||||
continue
|
||||
|
||||
if not event:
|
||||
return None
|
||||
|
||||
# `event` now refers to an object stored in `get_pdu_cache`. Our
|
||||
# callers may need to modify the returned object (eg to set
|
||||
# `event.internal_metadata.outlier = true`), so we return a copy
|
||||
# rather than the original object.
|
||||
event_copy = make_event_from_dict(
|
||||
event.get_pdu_json(),
|
||||
event.room_version,
|
||||
)
|
||||
|
||||
return event_copy
|
||||
|
||||
async def get_room_state_ids(
|
||||
self, destination: str, room_id: str, event_id: str
|
||||
|
@ -766,10 +766,24 @@ class FederationEventHandler:
|
||||
"""
|
||||
logger.info("Processing pulled event %s", event)
|
||||
|
||||
# these should not be outliers.
|
||||
assert (
|
||||
not event.internal_metadata.is_outlier()
|
||||
), "pulled event unexpectedly flagged as outlier"
|
||||
# This function should not be used to persist outliers (use something
|
||||
# else) because this does a bunch of operations that aren't necessary
|
||||
# (extra work; in particular, it makes sure we have all the prev_events
|
||||
# and resolves the state across those prev events). If you happen to run
|
||||
# into a situation where the event you're trying to process/backfill is
|
||||
# marked as an `outlier`, then you should update that spot to return an
|
||||
# `EventBase` copy that doesn't have `outlier` flag set.
|
||||
#
|
||||
# `EventBase` is used to represent both an event we have not yet
|
||||
# persisted, and one that we have persisted and now keep in the cache.
|
||||
# In an ideal world this method would only be called with the first type
|
||||
# of event, but it turns out that's not actually the case and for
|
||||
# example, you could get an event from cache that is marked as an
|
||||
# `outlier` (fix up that spot though).
|
||||
assert not event.internal_metadata.is_outlier(), (
|
||||
"Outlier event passed to _process_pulled_event. "
|
||||
"To persist an event as a non-outlier, make sure to pass in a copy without `event.internal_metadata.outlier = true`."
|
||||
)
|
||||
|
||||
event_id = event.event_id
|
||||
|
||||
|
@ -1346,9 +1346,24 @@ class PersistEventsStore:
|
||||
event_id: outlier for event_id, outlier in txn
|
||||
}
|
||||
|
||||
logger.debug(
|
||||
"_update_outliers_txn: events=%s have_persisted=%s",
|
||||
[ev.event_id for ev, _ in events_and_contexts],
|
||||
have_persisted,
|
||||
)
|
||||
|
||||
to_remove = set()
|
||||
for event, context in events_and_contexts:
|
||||
if event.event_id not in have_persisted:
|
||||
outlier_persisted = have_persisted.get(event.event_id)
|
||||
logger.debug(
|
||||
"_update_outliers_txn: event=%s outlier=%s outlier_persisted=%s",
|
||||
event.event_id,
|
||||
event.internal_metadata.is_outlier(),
|
||||
outlier_persisted,
|
||||
)
|
||||
|
||||
# Ignore events which we haven't persisted at all
|
||||
if outlier_persisted is None:
|
||||
continue
|
||||
|
||||
to_remove.add(event)
|
||||
@ -1358,7 +1373,6 @@ class PersistEventsStore:
|
||||
# was an outlier or not - what we have is at least as good.
|
||||
continue
|
||||
|
||||
outlier_persisted = have_persisted[event.event_id]
|
||||
if not event.internal_metadata.is_outlier() and outlier_persisted:
|
||||
# We received a copy of an event that we had already stored as
|
||||
# an outlier in the database. We now have some state at that event
|
||||
@ -1369,7 +1383,10 @@ class PersistEventsStore:
|
||||
# events down /sync. In general they will be historical events, so that
|
||||
# doesn't matter too much, but that is not always the case.
|
||||
|
||||
logger.info("Updating state for ex-outlier event %s", event.event_id)
|
||||
logger.info(
|
||||
"_update_outliers_txn: Updating state for ex-outlier event %s",
|
||||
event.event_id,
|
||||
)
|
||||
|
||||
# insert into event_to_state_groups.
|
||||
try:
|
||||
|
@ -22,6 +22,7 @@ from twisted.python.failure import Failure
|
||||
from twisted.test.proto_helpers import MemoryReactor
|
||||
|
||||
from synapse.api.room_versions import RoomVersions
|
||||
from synapse.events import EventBase
|
||||
from synapse.server import HomeServer
|
||||
from synapse.types import JsonDict
|
||||
from synapse.util import Clock
|
||||
@ -38,20 +39,24 @@ class FederationClientTest(FederatingHomeserverTestCase):
|
||||
self._mock_agent = mock.create_autospec(twisted.web.client.Agent, spec_set=True)
|
||||
homeserver.get_federation_http_client().agent = self._mock_agent
|
||||
|
||||
def test_get_room_state(self):
|
||||
creator = f"@creator:{self.OTHER_SERVER_NAME}"
|
||||
test_room_id = "!room_id"
|
||||
# Move clock up to somewhat realistic time so the PDU destination retry
|
||||
# works (`now` needs to be larger than `0 + PDU_RETRY_TIME_MS`).
|
||||
self.reactor.advance(1000000000)
|
||||
|
||||
self.creator = f"@creator:{self.OTHER_SERVER_NAME}"
|
||||
self.test_room_id = "!room_id"
|
||||
|
||||
def test_get_room_state(self):
|
||||
# mock up some events to use in the response.
|
||||
# In real life, these would have things in `prev_events` and `auth_events`, but that's
|
||||
# a bit annoying to mock up, and the code under test doesn't care, so we don't bother.
|
||||
create_event_dict = self.add_hashes_and_signatures_from_other_server(
|
||||
{
|
||||
"room_id": test_room_id,
|
||||
"room_id": self.test_room_id,
|
||||
"type": "m.room.create",
|
||||
"state_key": "",
|
||||
"sender": creator,
|
||||
"content": {"creator": creator},
|
||||
"sender": self.creator,
|
||||
"content": {"creator": self.creator},
|
||||
"prev_events": [],
|
||||
"auth_events": [],
|
||||
"origin_server_ts": 500,
|
||||
@ -59,10 +64,10 @@ class FederationClientTest(FederatingHomeserverTestCase):
|
||||
)
|
||||
member_event_dict = self.add_hashes_and_signatures_from_other_server(
|
||||
{
|
||||
"room_id": test_room_id,
|
||||
"room_id": self.test_room_id,
|
||||
"type": "m.room.member",
|
||||
"sender": creator,
|
||||
"state_key": creator,
|
||||
"sender": self.creator,
|
||||
"state_key": self.creator,
|
||||
"content": {"membership": "join"},
|
||||
"prev_events": [],
|
||||
"auth_events": [],
|
||||
@ -71,9 +76,9 @@ class FederationClientTest(FederatingHomeserverTestCase):
|
||||
)
|
||||
pl_event_dict = self.add_hashes_and_signatures_from_other_server(
|
||||
{
|
||||
"room_id": test_room_id,
|
||||
"room_id": self.test_room_id,
|
||||
"type": "m.room.power_levels",
|
||||
"sender": creator,
|
||||
"sender": self.creator,
|
||||
"state_key": "",
|
||||
"content": {},
|
||||
"prev_events": [],
|
||||
@ -103,7 +108,7 @@ class FederationClientTest(FederatingHomeserverTestCase):
|
||||
state_resp, auth_resp = self.get_success(
|
||||
self.hs.get_federation_client().get_room_state(
|
||||
"yet.another.server",
|
||||
test_room_id,
|
||||
self.test_room_id,
|
||||
"event_id",
|
||||
RoomVersions.V9,
|
||||
)
|
||||
@ -130,6 +135,102 @@ class FederationClientTest(FederatingHomeserverTestCase):
|
||||
["m.room.create", "m.room.member", "m.room.power_levels"],
|
||||
)
|
||||
|
||||
def test_get_pdu_returns_nothing_when_event_does_not_exist(self):
|
||||
"""No event should be returned when the event does not exist"""
|
||||
remote_pdu = self.get_success(
|
||||
self.hs.get_federation_client().get_pdu(
|
||||
["yet.another.server"],
|
||||
"event_should_not_exist",
|
||||
RoomVersions.V9,
|
||||
)
|
||||
)
|
||||
self.assertEqual(remote_pdu, None)
|
||||
|
||||
def test_get_pdu(self):
|
||||
"""Test to make sure an event is returned by `get_pdu()`"""
|
||||
self._get_pdu_once()
|
||||
|
||||
def test_get_pdu_event_from_cache_is_pristine(self):
|
||||
"""Test that modifications made to events returned by `get_pdu()`
|
||||
do not propagate back to to the internal cache (events returned should
|
||||
be a copy).
|
||||
"""
|
||||
|
||||
# Get the PDU in the cache
|
||||
remote_pdu = self._get_pdu_once()
|
||||
|
||||
# Modify the the event reference.
|
||||
# This change should not make it back to the `_get_pdu_cache`.
|
||||
remote_pdu.internal_metadata.outlier = True
|
||||
|
||||
# Get the event again. This time it should read it from cache.
|
||||
remote_pdu2 = self.get_success(
|
||||
self.hs.get_federation_client().get_pdu(
|
||||
["yet.another.server"],
|
||||
remote_pdu.event_id,
|
||||
RoomVersions.V9,
|
||||
)
|
||||
)
|
||||
|
||||
# Sanity check that we are working against the same event
|
||||
self.assertEqual(remote_pdu.event_id, remote_pdu2.event_id)
|
||||
|
||||
# Make sure the event does not include modification from earlier
|
||||
self.assertIsNotNone(remote_pdu2)
|
||||
self.assertEqual(remote_pdu2.internal_metadata.outlier, False)
|
||||
|
||||
def _get_pdu_once(self) -> EventBase:
|
||||
"""Retrieve an event via `get_pdu()` and assert that an event was returned.
|
||||
Also used to prime the cache for subsequent test logic.
|
||||
"""
|
||||
message_event_dict = self.add_hashes_and_signatures_from_other_server(
|
||||
{
|
||||
"room_id": self.test_room_id,
|
||||
"type": "m.room.message",
|
||||
"sender": self.creator,
|
||||
"state_key": "",
|
||||
"content": {},
|
||||
"prev_events": [],
|
||||
"auth_events": [],
|
||||
"origin_server_ts": 700,
|
||||
"depth": 10,
|
||||
}
|
||||
)
|
||||
|
||||
# mock up the response, and have the agent return it
|
||||
self._mock_agent.request.side_effect = lambda *args, **kwargs: defer.succeed(
|
||||
_mock_response(
|
||||
{
|
||||
"origin": "yet.another.server",
|
||||
"origin_server_ts": 900,
|
||||
"pdus": [
|
||||
message_event_dict,
|
||||
],
|
||||
}
|
||||
)
|
||||
)
|
||||
|
||||
remote_pdu = self.get_success(
|
||||
self.hs.get_federation_client().get_pdu(
|
||||
["yet.another.server"],
|
||||
"event_id",
|
||||
RoomVersions.V9,
|
||||
)
|
||||
)
|
||||
|
||||
# check the right call got made to the agent
|
||||
self._mock_agent.request.assert_called_once_with(
|
||||
b"GET",
|
||||
b"matrix://yet.another.server/_matrix/federation/v1/event/event_id",
|
||||
headers=mock.ANY,
|
||||
bodyProducer=None,
|
||||
)
|
||||
|
||||
self.assertIsNotNone(remote_pdu)
|
||||
self.assertEqual(remote_pdu.internal_metadata.outlier, False)
|
||||
|
||||
return remote_pdu
|
||||
|
||||
|
||||
def _mock_response(resp: JsonDict):
|
||||
body = json.dumps(resp).encode("utf-8")
|
||||
|
Loading…
Reference in New Issue
Block a user