synapse/tests/federation/test_federation_client.py
Eric Eastwood 0f971ca68e
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)).
2022-07-20 15:58:51 -05:00

250 lines
8.8 KiB
Python

# Copyright 2022 Matrix.org Federation C.I.C
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
import json
from unittest import mock
import twisted.web.client
from twisted.internet import defer
from twisted.internet.protocol import Protocol
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
from tests.unittest import FederatingHomeserverTestCase
class FederationClientTest(FederatingHomeserverTestCase):
def prepare(self, reactor: MemoryReactor, clock: Clock, homeserver: HomeServer):
super().prepare(reactor, clock, homeserver)
# mock out the Agent used by the federation client, which is easier than
# catching the HTTPS connection and do the TLS stuff.
self._mock_agent = mock.create_autospec(twisted.web.client.Agent, spec_set=True)
homeserver.get_federation_http_client().agent = self._mock_agent
# 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": self.test_room_id,
"type": "m.room.create",
"state_key": "",
"sender": self.creator,
"content": {"creator": self.creator},
"prev_events": [],
"auth_events": [],
"origin_server_ts": 500,
}
)
member_event_dict = self.add_hashes_and_signatures_from_other_server(
{
"room_id": self.test_room_id,
"type": "m.room.member",
"sender": self.creator,
"state_key": self.creator,
"content": {"membership": "join"},
"prev_events": [],
"auth_events": [],
"origin_server_ts": 600,
}
)
pl_event_dict = self.add_hashes_and_signatures_from_other_server(
{
"room_id": self.test_room_id,
"type": "m.room.power_levels",
"sender": self.creator,
"state_key": "",
"content": {},
"prev_events": [],
"auth_events": [],
"origin_server_ts": 700,
}
)
# mock up the response, and have the agent return it
self._mock_agent.request.side_effect = lambda *args, **kwargs: defer.succeed(
_mock_response(
{
"pdus": [
create_event_dict,
member_event_dict,
pl_event_dict,
],
"auth_chain": [
create_event_dict,
member_event_dict,
],
}
)
)
# now fire off the request
state_resp, auth_resp = self.get_success(
self.hs.get_federation_client().get_room_state(
"yet.another.server",
self.test_room_id,
"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/state/%21room_id?event_id=event_id",
headers=mock.ANY,
bodyProducer=None,
)
# ... and that the response is correct.
# the auth_resp should be empty because all the events are also in state
self.assertEqual(auth_resp, [])
# all of the events should be returned in state_resp, though not necessarily
# in the same order. We just check the type on the assumption that if the type
# is right, so is the rest of the event.
self.assertCountEqual(
[e.type for e in state_resp],
["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")
def deliver_body(p: Protocol):
p.dataReceived(body)
p.connectionLost(Failure(twisted.web.client.ResponseDone()))
response = mock.Mock(
code=200,
phrase=b"OK",
headers=twisted.web.client.Headers({"content-Type": ["application/json"]}),
length=len(body),
deliverBody=deliver_body,
)
mock.seal(response)
return response