MatrixSynapse/synapse/handlers/read_marker.py

91 lines
3.5 KiB
Python

# -*- coding: utf-8 -*-
# Copyright 2015, 2016 OpenMarket Ltd
#
# 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.
from ._base import BaseHandler
from twisted.internet import defer
from synapse.util.async import Linearizer
from synapse.api.errors import SynapseError
import logging
logger = logging.getLogger(__name__)
class ReadMarkerHandler(BaseHandler):
def __init__(self, hs):
super(ReadMarkerHandler, self).__init__(hs)
self.server_name = hs.config.server_name
self.store = hs.get_datastore()
self.read_marker_linearizer = Linearizer(name="read_marker")
self.notifier = hs.get_notifier()
@defer.inlineCallbacks
def received_client_read_marker(self, room_id, user_id, event_id):
"""Updates the read marker for a given user in a given room if the event ID given
is ahead in the stream relative to the current read marker.
This uses a notifier to indicate that account data should be sent down /sync if
the read marker has changed.
"""
# Get ordering for existing read marker
with (yield self.read_marker_linearizer.queue(room_id + "_" + user_id)):
account_data = yield self.store.get_account_data_for_room(user_id, room_id)
existing_read_marker = account_data["m.read_marker"]
should_update = True
res = yield self.store._simple_select_one(
table="events",
retcols=["topological_ordering", "stream_ordering"],
keyvalues={"event_id": event_id},
allow_none=True
)
if not res:
raise SynapseError(404, 'Event does not exist')
if existing_read_marker:
new_to = int(res["topological_ordering"])
new_so = int(res["stream_ordering"])
# Get ordering for existing read marker
res = yield self.store._simple_select_one(
table="events",
retcols=["topological_ordering", "stream_ordering"],
keyvalues={"event_id": existing_read_marker['marker']},
allow_none=True
)
existing_to = int(res["topological_ordering"]) if res else None
existing_so = int(res["stream_ordering"]) if res else None
# Prevent updating if the existing marker is ahead in the stream
if existing_to > new_to:
should_update = False
elif existing_to == new_to and existing_so >= new_so:
should_update = False
if should_update:
content = {
"marker": event_id
}
max_id = yield self.store.add_account_data_to_room(
user_id, room_id, "m.read_marker", content
)
self.notifier.on_new_event(
"account_data_key", max_id, users=[user_id], rooms=[room_id]
)