# -*- coding: utf-8 -*-
# Copyright 2014-2016 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.
import logging
import random
from twisted.internet import defer
from synapse.api.constants import EventTypes, Membership
from synapse.api.errors import AuthError, SynapseError
from synapse.events import EventBase
from synapse.events.utils import serialize_event
from synapse.types import UserID
from synapse.util.logutils import log_function
from synapse.visibility import filter_events_for_client
from ._base import BaseHandler
logger = logging.getLogger(__name__)
class EventStreamHandler(BaseHandler):
def __init__(self, hs):
super(EventStreamHandler, self).__init__(hs)
# Count of active streams per user
self._streams_per_user = {}
# Grace timers per user to delay the "stopped" signal
self._stop_timer_per_user = {}
self.distributor = hs.get_distributor()
self.distributor.declare("started_user_eventstream")
self.distributor.declare("stopped_user_eventstream")
self.clock = hs.get_clock()
self.notifier = hs.get_notifier()
self.state = hs.get_state_handler()
self._server_notices_sender = hs.get_server_notices_sender()
@defer.inlineCallbacks
@log_function
def get_stream(self, auth_user_id, pagin_config, timeout=0,
as_client_event=True, affect_presence=True,
only_keys=None, room_id=None, is_guest=False):
"""Fetches the events stream for a given user.
If `only_keys` is not None, events from keys will be sent down.
"""
if room_id:
blocked = yield self.store.is_room_blocked(room_id)
if blocked:
raise SynapseError(403, "This room has been blocked on this server")
# send any outstanding server notices to the user.
yield self._server_notices_sender.on_user_syncing(auth_user_id)
auth_user = UserID.from_string(auth_user_id)
presence_handler = self.hs.get_presence_handler()
context = yield presence_handler.user_syncing(
auth_user_id, affect_presence=affect_presence,
)
with context:
if timeout:
# If they've set a timeout set a minimum limit.
timeout = max(timeout, 500)
# Add some randomness to this value to try and mitigate against
# thundering herds on restart.
timeout = random.randint(int(timeout * 0.9), int(timeout * 1.1))
events, tokens = yield self.notifier.get_events_for(
auth_user, pagin_config, timeout,
only_keys=only_keys,
is_guest=is_guest, explicit_room_id=room_id
)
# When the user joins a new room, or another user joins a currently
# joined room, we need to send down presence for those users.
to_add = []
for event in events:
if not isinstance(event, EventBase):
continue
if event.type == EventTypes.Member:
if event.membership != Membership.JOIN:
continue
# Send down presence.
if event.state_key == auth_user_id:
# Send down presence for everyone in the room.
users = yield self.state.get_current_users_in_room(event.room_id)
states = yield presence_handler.get_states(
users,
as_event=True,
)
to_add.extend(states)
else:
ev = yield presence_handler.get_state(
UserID.from_string(event.state_key),
as_event=True,
)
to_add.append(ev)
events.extend(to_add)
time_now = self.clock.time_msec()
chunks = [
serialize_event(e, time_now, as_client_event) for e in events
]
chunk = {
"chunk": chunks,
"start": tokens[0].to_string(),
"end": tokens[1].to_string(),
}
defer.returnValue(chunk)
class EventHandler(BaseHandler):
@defer.inlineCallbacks
def get_event(self, user, room_id, event_id):
"""Retrieve a single specified event.
Args:
user (synapse.types.UserID): The user requesting the event
room_id (str|None): The expected room id. We'll return None if the
event's room does not match.
event_id (str): The event ID to obtain.
Returns:
dict: An event, or None if there is no event matching this ID.
Raises:
SynapseError if there was a problem retrieving this event, or
AuthError if the user does not have the rights to inspect this
event.
"""
event = yield self.store.get_event(event_id, check_room_id=room_id)
if not event:
defer.returnValue(None)
return
users = yield self.store.get_users_in_room(event.room_id)
is_peeking = user.to_string() not in users
filtered = yield filter_events_for_client(
self.store,
user.to_string(),
[event],
is_peeking=is_peeking
)
if not filtered:
raise AuthError(
403,
"You don't have permission to access that event."
)
defer.returnValue(event)