Fix sync bug when accepting invites (#4956)

Hopefully this time we really will fix #4422.

We need to make sure that the cache on
`get_rooms_for_user_with_stream_ordering` is invalidated *before* the
SyncHandler is notified for the new events, and we can now do so reliably via
the `events` stream.
This commit is contained in:
Richard van der Hoff 2019-04-02 12:42:39 +01:00 committed by GitHub
parent 4c552ed78a
commit 297bf2547e
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GPG Key ID: 4AEE18F83AFDEB23
7 changed files with 237 additions and 69 deletions

1
changelog.d/4956.bugfix Normal file
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@ -0,0 +1 @@
Fix sync bug which made accepting invites unreliable in worker-mode synapses.

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@ -16,7 +16,10 @@
import logging
from synapse.api.constants import EventTypes
from synapse.replication.tcp.streams.events import EventsStreamEventRow
from synapse.replication.tcp.streams.events import (
EventsStreamCurrentStateRow,
EventsStreamEventRow,
)
from synapse.storage.event_federation import EventFederationWorkerStore
from synapse.storage.event_push_actions import EventPushActionsWorkerStore
from synapse.storage.events_worker import EventsWorkerStore
@ -80,14 +83,7 @@ class SlavedEventStore(EventFederationWorkerStore,
if stream_name == "events":
self._stream_id_gen.advance(token)
for row in rows:
if row.type != EventsStreamEventRow.TypeId:
continue
data = row.data
self.invalidate_caches_for_event(
token, data.event_id, data.room_id, data.type, data.state_key,
data.redacts,
backfilled=False,
)
self._process_event_stream_row(token, row)
elif stream_name == "backfill":
self._backfill_id_gen.advance(-token)
for row in rows:
@ -100,6 +96,23 @@ class SlavedEventStore(EventFederationWorkerStore,
stream_name, token, rows
)
def _process_event_stream_row(self, token, row):
data = row.data
if row.type == EventsStreamEventRow.TypeId:
self.invalidate_caches_for_event(
token, data.event_id, data.room_id, data.type, data.state_key,
data.redacts,
backfilled=False,
)
elif row.type == EventsStreamCurrentStateRow.TypeId:
if data.type == EventTypes.Member:
self.get_rooms_for_user_with_stream_ordering.invalidate(
(data.state_key, ),
)
else:
raise Exception("Unknown events stream row type %s" % (row.type, ))
def invalidate_caches_for_event(self, stream_ordering, event_id, room_id,
etype, state_key, redacts, backfilled):
self._invalidate_get_event_cache(event_id)

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@ -1355,11 +1355,6 @@ class SQLBaseStore(object):
members_changed (iterable[str]): The user_ids of members that have
changed
"""
for member in members_changed:
self._attempt_to_invalidate_cache(
"get_rooms_for_user_with_stream_ordering", (member,),
)
for host in set(get_domain_from_id(u) for u in members_changed):
self._attempt_to_invalidate_cache(
"is_host_joined", (room_id, host,),

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@ -79,7 +79,7 @@ def encode_json(json_object):
"""
out = frozendict_json_encoder.encode(json_object)
if isinstance(out, bytes):
out = out.decode('utf8')
out = out.decode("utf8")
return out
@ -813,9 +813,10 @@ class EventsStore(
"""
all_events_and_contexts = events_and_contexts
min_stream_order = events_and_contexts[0][0].internal_metadata.stream_ordering
max_stream_order = events_and_contexts[-1][0].internal_metadata.stream_ordering
self._update_current_state_txn(txn, state_delta_for_room, max_stream_order)
self._update_current_state_txn(txn, state_delta_for_room, min_stream_order)
self._update_forward_extremities_txn(
txn,
@ -890,7 +891,7 @@ class EventsStore(
backfilled=backfilled,
)
def _update_current_state_txn(self, txn, state_delta_by_room, max_stream_order):
def _update_current_state_txn(self, txn, state_delta_by_room, stream_id):
for room_id, current_state_tuple in iteritems(state_delta_by_room):
to_delete, to_insert = current_state_tuple
@ -899,6 +900,12 @@ class EventsStore(
# that we can use it to calculate the `prev_event_id`. (This
# allows us to not have to pull out the existing state
# unnecessarily).
#
# The stream_id for the update is chosen to be the minimum of the stream_ids
# for the batch of the events that we are persisting; that means we do not
# end up in a situation where workers see events before the
# current_state_delta updates.
#
sql = """
INSERT INTO current_state_delta_stream
(stream_id, room_id, type, state_key, event_id, prev_event_id)
@ -911,7 +918,7 @@ class EventsStore(
sql,
(
(
max_stream_order,
stream_id,
room_id,
etype,
state_key,
@ -929,7 +936,7 @@ class EventsStore(
sql,
(
(
max_stream_order,
stream_id,
room_id,
etype,
state_key,
@ -970,7 +977,7 @@ class EventsStore(
txn.call_after(
self._curr_state_delta_stream_cache.entity_has_changed,
room_id,
max_stream_order,
stream_id,
)
# Invalidate the various caches
@ -986,6 +993,11 @@ class EventsStore(
if ev_type == EventTypes.Member
)
for member in members_changed:
txn.call_after(
self.get_rooms_for_user_with_stream_ordering.invalidate, (member,)
)
self._invalidate_state_caches_and_stream(txn, room_id, members_changed)
def _update_forward_extremities_txn(

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@ -56,7 +56,9 @@ class BaseSlavedStoreTestCase(unittest.HomeserverTestCase):
client = client_factory.buildProtocol(None)
client.makeConnection(FakeTransport(server, reactor))
server.makeConnection(FakeTransport(client, reactor))
self.server_to_client_transport = FakeTransport(client, reactor)
server.makeConnection(self.server_to_client_transport)
def replicate(self):
"""Tell the master side of replication that something has happened, and then
@ -69,6 +71,24 @@ class BaseSlavedStoreTestCase(unittest.HomeserverTestCase):
master_result = self.get_success(getattr(self.master_store, method)(*args))
slaved_result = self.get_success(getattr(self.slaved_store, method)(*args))
if expected_result is not None:
self.assertEqual(master_result, expected_result)
self.assertEqual(slaved_result, expected_result)
self.assertEqual(master_result, slaved_result)
self.assertEqual(
master_result,
expected_result,
"Expected master result to be %r but was %r" % (
expected_result, master_result
),
)
self.assertEqual(
slaved_result,
expected_result,
"Expected slave result to be %r but was %r" % (
expected_result, slaved_result
),
)
self.assertEqual(
master_result,
slaved_result,
"Slave result %r does not match master result %r" % (
slaved_result, master_result
),
)

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@ -11,11 +11,13 @@
# 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 logging
from canonicaljson import encode_canonical_json
from synapse.events import FrozenEvent, _EventInternalMetadata
from synapse.events.snapshot import EventContext
from synapse.handlers.room import RoomEventSource
from synapse.replication.slave.storage.events import SlavedEventStore
from synapse.storage.roommember import RoomsForUser
@ -26,6 +28,8 @@ USER_ID_2 = "@bright:blue"
OUTLIER = {"outlier": True}
ROOM_ID = "!room:blue"
logger = logging.getLogger(__name__)
def dict_equals(self, other):
me = encode_canonical_json(self.get_pdu_json())
@ -172,18 +176,142 @@ class SlavedEventStoreTestCase(BaseSlavedStoreTestCase):
{"highlight_count": 1, "notify_count": 2},
)
def test_get_rooms_for_user_with_stream_ordering(self):
"""Check that the cache on get_rooms_for_user_with_stream_ordering is invalidated
by rows in the events stream
"""
self.persist(type="m.room.create", key="", creator=USER_ID)
self.persist(type="m.room.member", key=USER_ID, membership="join")
self.replicate()
self.check("get_rooms_for_user_with_stream_ordering", (USER_ID_2,), set())
j2 = self.persist(
type="m.room.member", sender=USER_ID_2, key=USER_ID_2, membership="join"
)
self.replicate()
self.check(
"get_rooms_for_user_with_stream_ordering",
(USER_ID_2,),
{(ROOM_ID, j2.internal_metadata.stream_ordering)},
)
def test_get_rooms_for_user_with_stream_ordering_with_multi_event_persist(self):
"""Check that current_state invalidation happens correctly with multiple events
in the persistence batch.
This test attempts to reproduce a race condition between the event persistence
loop and a worker-based Sync handler.
The problem occurred when the master persisted several events in one batch. It
only updates the current_state at the end of each batch, so the obvious thing
to do is then to issue a current_state_delta stream update corresponding to the
last stream_id in the batch.
However, that raises the possibility that a worker will see the replication
notification for a join event before the current_state caches are invalidated.
The test involves:
* creating a join and a message event for a user, and persisting them in the
same batch
* controlling the replication stream so that updates are sent gradually
* between each bunch of replication updates, check that we see a consistent
snapshot of the state.
"""
self.persist(type="m.room.create", key="", creator=USER_ID)
self.persist(type="m.room.member", key=USER_ID, membership="join")
self.replicate()
self.check("get_rooms_for_user_with_stream_ordering", (USER_ID_2,), set())
# limit the replication rate
repl_transport = self.server_to_client_transport
repl_transport.autoflush = False
# build the join and message events and persist them in the same batch.
logger.info("----- build test events ------")
j2, j2ctx = self.build_event(
type="m.room.member", sender=USER_ID_2, key=USER_ID_2, membership="join"
)
msg, msgctx = self.build_event()
self.get_success(self.master_store.persist_events([
(j2, j2ctx),
(msg, msgctx),
]))
self.replicate()
event_source = RoomEventSource(self.hs)
event_source.store = self.slaved_store
current_token = self.get_success(event_source.get_current_key())
# gradually stream out the replication
while repl_transport.buffer:
logger.info("------ flush ------")
repl_transport.flush(30)
self.pump(0)
prev_token = current_token
current_token = self.get_success(event_source.get_current_key())
# attempt to replicate the behaviour of the sync handler.
#
# First, we get a list of the rooms we are joined to
joined_rooms = self.get_success(
self.slaved_store.get_rooms_for_user_with_stream_ordering(
USER_ID_2,
),
)
# Then, we get a list of the events since the last sync
membership_changes = self.get_success(
self.slaved_store.get_membership_changes_for_user(
USER_ID_2, prev_token, current_token,
)
)
logger.info(
"%s->%s: joined_rooms=%r membership_changes=%r",
prev_token,
current_token,
joined_rooms,
membership_changes,
)
# the membership change is only any use to us if the room is in the
# joined_rooms list.
if membership_changes:
self.assertEqual(
joined_rooms, {(ROOM_ID, j2.internal_metadata.stream_ordering)}
)
event_id = 0
def persist(
def persist(self, backfill=False, **kwargs):
"""
Returns:
synapse.events.FrozenEvent: The event that was persisted.
"""
event, context = self.build_event(**kwargs)
if backfill:
self.get_success(
self.master_store.persist_events([(event, context)], backfilled=True)
)
else:
self.get_success(
self.master_store.persist_event(event, context)
)
return event
def build_event(
self,
sender=USER_ID,
room_id=ROOM_ID,
type={},
type="m.room.message",
key=None,
internal={},
state=None,
reset_state=False,
backfill=False,
depth=None,
prev_events=[],
auth_events=[],
@ -192,10 +320,7 @@ class SlavedEventStoreTestCase(BaseSlavedStoreTestCase):
push_actions=[],
**content
):
"""
Returns:
synapse.events.FrozenEvent: The event that was persisted.
"""
if depth is None:
depth = self.event_id
@ -234,23 +359,11 @@ class SlavedEventStoreTestCase(BaseSlavedStoreTestCase):
)
else:
state_handler = self.hs.get_state_handler()
context = self.get_success(state_handler.compute_event_context(event))
context = self.get_success(state_handler.compute_event_context(
event
))
self.master_store.add_push_actions_to_staging(
event.event_id, {user_id: actions for user_id, actions in push_actions}
)
ordering = None
if backfill:
self.get_success(
self.master_store.persist_events([(event, context)], backfilled=True)
)
else:
ordering, _ = self.get_success(
self.master_store.persist_event(event, context)
)
if ordering:
event.internal_metadata.stream_ordering = ordering
return event
return event, context

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@ -365,6 +365,7 @@ class FakeTransport(object):
disconnected = False
buffer = attr.ib(default=b'')
producer = attr.ib(default=None)
autoflush = attr.ib(default=True)
def getPeer(self):
return None
@ -415,7 +416,17 @@ class FakeTransport(object):
def write(self, byt):
self.buffer = self.buffer + byt
def _write():
# always actually do the write asynchronously. Some protocols (notably the
# TLSMemoryBIOProtocol) get very confused if a read comes back while they are
# still doing a write. Doing a callLater here breaks the cycle.
if self.autoflush:
self._reactor.callLater(0.0, self.flush)
def writeSequence(self, seq):
for x in seq:
self.write(x)
def flush(self, maxbytes=None):
if not self.buffer:
# nothing to do. Don't write empty buffers: it upsets the
# TLSMemoryBIOProtocol
@ -423,23 +434,26 @@ class FakeTransport(object):
if self.disconnected:
return
logger.info("%s->%s: %s", self._protocol, self.other, self.buffer)
if getattr(self.other, "transport") is not None:
if getattr(self.other, "transport") is None:
# the other has no transport yet; reschedule
if self.autoflush:
self._reactor.callLater(0.0, self.flush)
return
if maxbytes is not None:
to_write = self.buffer[:maxbytes]
else:
to_write = self.buffer
logger.info("%s->%s: %s", self._protocol, self.other, to_write)
try:
self.other.dataReceived(self.buffer)
self.buffer = b""
self.other.dataReceived(to_write)
except Exception as e:
logger.warning("Exception writing to protocol: %s", e)
return
self._reactor.callLater(0.0, _write)
# always actually do the write asynchronously. Some protocols (notably the
# TLSMemoryBIOProtocol) get very confused if a read comes back while they are
# still doing a write. Doing a callLater here breaks the cycle.
self._reactor.callLater(0.0, _write)
def writeSequence(self, seq):
for x in seq:
self.write(x)
self.buffer = self.buffer[len(to_write):]
if self.buffer and self.autoflush:
self._reactor.callLater(0.0, self.flush)