synapse-product/synapse/handlers/sync.py
2015-08-11 11:30:59 +01:00

500 lines
18 KiB
Python

# -*- coding: utf-8 -*-
# Copyright 2015 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 synapse.streams.config import PaginationConfig
from synapse.api.constants import Membership, EventTypes
from twisted.internet import defer
import collections
import logging
logger = logging.getLogger(__name__)
SyncConfig = collections.namedtuple("SyncConfig", [
"user",
"client_info",
"limit",
"gap",
"sort",
"backfill",
"filter",
])
class RoomSyncResult(collections.namedtuple("RoomSyncResult", [
"room_id",
"limited",
"published",
"events",
"state",
"prev_batch",
"ephemeral",
])):
__slots__ = []
def __nonzero__(self):
"""Make the result appear empty if there are no updates. This is used
to tell if room needs to be part of the sync result.
"""
return bool(self.events or self.state or self.ephemeral)
class SyncResult(collections.namedtuple("SyncResult", [
"next_batch", # Token for the next sync
"private_user_data", # List of private events for the user.
"public_user_data", # List of public events for all users.
"rooms", # RoomSyncResult for each room.
])):
__slots__ = []
def __nonzero__(self):
"""Make the result appear empty if there are no updates. This is used
to tell if the notifier needs to wait for more events when polling for
events.
"""
return bool(
self.private_user_data or self.public_user_data or self.rooms
)
class SyncHandler(BaseHandler):
def __init__(self, hs):
super(SyncHandler, self).__init__(hs)
self.event_sources = hs.get_event_sources()
self.clock = hs.get_clock()
@defer.inlineCallbacks
def wait_for_sync_for_user(self, sync_config, since_token=None, timeout=0):
"""Get the sync for a client if we have new data for it now. Otherwise
wait for new data to arrive on the server. If the timeout expires, then
return an empty sync result.
Returns:
A Deferred SyncResult.
"""
if timeout == 0 or since_token is None:
result = yield self.current_sync_for_user(sync_config, since_token)
defer.returnValue(result)
else:
def current_sync_callback(before_token, after_token):
return self.current_sync_for_user(sync_config, since_token)
rm_handler = self.hs.get_handlers().room_member_handler
room_ids = yield rm_handler.get_joined_rooms_for_user(
sync_config.user
)
result = yield self.notifier.wait_for_events(
sync_config.user, room_ids,
sync_config.filter, timeout, current_sync_callback
)
defer.returnValue(result)
def current_sync_for_user(self, sync_config, since_token=None):
"""Get the sync for client needed to match what the server has now.
Returns:
A Deferred SyncResult.
"""
if since_token is None:
return self.initial_sync(sync_config)
else:
if sync_config.gap:
return self.incremental_sync_with_gap(sync_config, since_token)
else:
# TODO(mjark): Handle gapless sync
raise NotImplementedError()
@defer.inlineCallbacks
def initial_sync(self, sync_config):
"""Get a sync for a client which is starting without any state
Returns:
A Deferred SyncResult.
"""
if sync_config.sort == "timeline,desc":
# TODO(mjark): Handle going through events in reverse order?.
# What does "most recent events" mean when applying the limits mean
# in this case?
raise NotImplementedError()
now_token = yield self.event_sources.get_current_token()
presence_stream = self.event_sources.sources["presence"]
# TODO (mjark): This looks wrong, shouldn't we be getting the presence
# UP to the present rather than after the present?
pagination_config = PaginationConfig(from_token=now_token)
presence, _ = yield presence_stream.get_pagination_rows(
user=sync_config.user,
pagination_config=pagination_config.get_source_config("presence"),
key=None
)
room_list = yield self.store.get_rooms_for_user_where_membership_is(
user_id=sync_config.user.to_string(),
membership_list=[Membership.INVITE, Membership.JOIN]
)
# TODO (mjark): Does public mean "published"?
published_rooms = yield self.store.get_rooms(is_public=True)
published_room_ids = set(r["room_id"] for r in published_rooms)
rooms = []
for event in room_list:
room_sync = yield self.initial_sync_for_room(
event.room_id, sync_config, now_token, published_room_ids
)
rooms.append(room_sync)
defer.returnValue(SyncResult(
public_user_data=presence,
private_user_data=[],
rooms=rooms,
next_batch=now_token,
))
@defer.inlineCallbacks
def initial_sync_for_room(self, room_id, sync_config, now_token,
published_room_ids):
"""Sync a room for a client which is starting without any state
Returns:
A Deferred RoomSyncResult.
"""
recents, prev_batch_token, limited = yield self.load_filtered_recents(
room_id, sync_config, now_token,
)
current_state = yield self.state_handler.get_current_state(
room_id
)
current_state_events = current_state.values()
defer.returnValue(RoomSyncResult(
room_id=room_id,
published=room_id in published_room_ids,
events=recents,
prev_batch=prev_batch_token,
state=current_state_events,
limited=limited,
ephemeral=[],
))
@defer.inlineCallbacks
def incremental_sync_with_gap(self, sync_config, since_token):
""" Get the incremental delta needed to bring the client up to
date with the server.
Returns:
A Deferred SyncResult.
"""
if sync_config.sort == "timeline,desc":
# TODO(mjark): Handle going through events in reverse order?.
# What does "most recent events" mean when applying the limits mean
# in this case?
raise NotImplementedError()
now_token = yield self.event_sources.get_current_token()
presence_source = self.event_sources.sources["presence"]
presence, presence_key = yield presence_source.get_new_events_for_user(
user=sync_config.user,
from_key=since_token.presence_key,
limit=sync_config.limit,
)
now_token = now_token.copy_and_replace("presence_key", presence_key)
typing_source = self.event_sources.sources["typing"]
typing, typing_key = yield typing_source.get_new_events_for_user(
user=sync_config.user,
from_key=since_token.typing_key,
limit=sync_config.limit,
)
now_token = now_token.copy_and_replace("typing_key", typing_key)
typing_by_room = {event["room_id"]: [event] for event in typing}
for event in typing:
event.pop("room_id")
logger.debug("Typing %r", typing_by_room)
rm_handler = self.hs.get_handlers().room_member_handler
room_ids = yield rm_handler.get_joined_rooms_for_user(sync_config.user)
# TODO (mjark): Does public mean "published"?
published_rooms = yield self.store.get_rooms(is_public=True)
published_room_ids = set(r["room_id"] for r in published_rooms)
room_events, _ = yield self.store.get_room_events_stream(
sync_config.user.to_string(),
from_key=since_token.room_key,
to_key=now_token.room_key,
room_id=None,
limit=sync_config.limit + 1,
)
rooms = []
if len(room_events) <= sync_config.limit:
# There is no gap in any of the rooms. Therefore we can just
# partition the new events by room and return them.
events_by_room_id = {}
for event in room_events:
events_by_room_id.setdefault(event.room_id, []).append(event)
for room_id in room_ids:
recents = events_by_room_id.get(room_id, [])
state = [event for event in recents if event.is_state()]
if recents:
prev_batch = now_token.copy_and_replace(
"room_key", recents[0].internal_metadata.before
)
else:
prev_batch = now_token
state = yield self.check_joined_room(
sync_config, room_id, state
)
room_sync = RoomSyncResult(
room_id=room_id,
published=room_id in published_room_ids,
events=recents,
prev_batch=prev_batch,
state=state,
limited=False,
ephemeral=typing_by_room.get(room_id, [])
)
if room_sync:
rooms.append(room_sync)
else:
for room_id in room_ids:
room_sync = yield self.incremental_sync_with_gap_for_room(
room_id, sync_config, since_token, now_token,
published_room_ids, typing_by_room
)
if room_sync:
rooms.append(room_sync)
defer.returnValue(SyncResult(
public_user_data=presence,
private_user_data=[],
rooms=rooms,
next_batch=now_token,
))
@defer.inlineCallbacks
def _filter_events_for_client(self, user_id, room_id, events):
event_id_to_state = yield self.store.get_state_for_events(
room_id, frozenset(e.event_id for e in events),
types=(
(EventTypes.RoomHistoryVisibility, ""),
(EventTypes.Member, user_id),
)
)
def allowed(event_and_state):
event, state = event_and_state
if event.type == EventTypes.RoomHistoryVisibility:
return True
membership_ev = state.get((EventTypes.Member, user_id), None)
if membership_ev:
membership = membership_ev.membership
else:
membership = Membership.LEAVE
if membership == Membership.JOIN:
return True
history = state.get((EventTypes.RoomHistoryVisibility, ''), None)
if history:
visibility = history.content.get("history_visibility", "shared")
else:
visibility = "shared"
if visibility == "public":
return True
elif visibility == "shared":
return True
elif visibility == "joined":
return membership == Membership.JOIN
elif visibility == "invited":
return membership == Membership.INVITE
return True
event_and_state = filter(
allowed,
[
(e, event_id_to_state[e.event_id])
for e in events
]
)
defer.returnValue([
ev
for ev, _ in event_and_state
])
@defer.inlineCallbacks
def load_filtered_recents(self, room_id, sync_config, now_token,
since_token=None):
limited = True
recents = []
filtering_factor = 2
load_limit = max(sync_config.limit * filtering_factor, 100)
max_repeat = 3 # Only try a few times per room, otherwise
room_key = now_token.room_key
end_key = room_key
while limited and len(recents) < sync_config.limit and max_repeat:
events, keys = yield self.store.get_recent_events_for_room(
room_id,
limit=load_limit + 1,
from_token=since_token.room_key if since_token else None,
end_token=end_key,
)
(room_key, _) = keys
end_key = "s" + room_key.split('-')[-1]
loaded_recents = sync_config.filter.filter_room_events(events)
loaded_recents = yield self._filter_events_for_client(
sync_config.user.to_string(), room_id, loaded_recents,
)
loaded_recents.extend(recents)
recents = loaded_recents
if len(events) <= load_limit:
limited = False
max_repeat -= 1
if len(recents) > sync_config.limit:
recents = recents[-sync_config.limit:]
room_key = recents[0].internal_metadata.before
prev_batch_token = now_token.copy_and_replace(
"room_key", room_key
)
defer.returnValue((recents, prev_batch_token, limited))
@defer.inlineCallbacks
def incremental_sync_with_gap_for_room(self, room_id, sync_config,
since_token, now_token,
published_room_ids, typing_by_room):
""" Get the incremental delta needed to bring the client up to date for
the room. Gives the client the most recent events and the changes to
state.
Returns:
A Deferred RoomSyncResult
"""
# TODO(mjark): Check for redactions we might have missed.
recents, prev_batch_token, limited = yield self.load_filtered_recents(
room_id, sync_config, now_token, since_token,
)
logging.debug("Recents %r", recents)
# TODO(mjark): This seems racy since this isn't being passed a
# token to indicate what point in the stream this is
current_state = yield self.state_handler.get_current_state(
room_id
)
current_state_events = current_state.values()
state_at_previous_sync = yield self.get_state_at_previous_sync(
room_id, since_token=since_token
)
state_events_delta = yield self.compute_state_delta(
since_token=since_token,
previous_state=state_at_previous_sync,
current_state=current_state_events,
)
state_events_delta = yield self.check_joined_room(
sync_config, room_id, state_events_delta
)
room_sync = RoomSyncResult(
room_id=room_id,
published=room_id in published_room_ids,
events=recents,
prev_batch=prev_batch_token,
state=state_events_delta,
limited=limited,
ephemeral=typing_by_room.get(room_id, [])
)
logging.debug("Room sync: %r", room_sync)
defer.returnValue(room_sync)
@defer.inlineCallbacks
def get_state_at_previous_sync(self, room_id, since_token):
""" Get the room state at the previous sync the client made.
Returns:
A Deferred list of Events.
"""
last_events, token = yield self.store.get_recent_events_for_room(
room_id, end_token=since_token.room_key, limit=1,
)
if last_events:
last_event = last_events[0]
last_context = yield self.state_handler.compute_event_context(
last_event
)
if last_event.is_state():
state = [last_event] + last_context.current_state.values()
else:
state = last_context.current_state.values()
else:
state = ()
defer.returnValue(state)
def compute_state_delta(self, since_token, previous_state, current_state):
""" Works out the differnce in state between the current state and the
state the client got when it last performed a sync.
Returns:
A list of events.
"""
# TODO(mjark) Check if the state events were received by the server
# after the previous sync, since we need to include those state
# updates even if they occured logically before the previous event.
# TODO(mjark) Check for new redactions in the state events.
previous_dict = {event.event_id: event for event in previous_state}
state_delta = []
for event in current_state:
if event.event_id not in previous_dict:
state_delta.append(event)
return state_delta
@defer.inlineCallbacks
def check_joined_room(self, sync_config, room_id, state_delta):
joined = False
for event in state_delta:
if (
event.type == EventTypes.Member
and event.state_key == sync_config.user.to_string()
):
if event.content["membership"] == Membership.JOIN:
joined = True
if joined:
res = yield self.state_handler.get_current_state(room_id)
state_delta = res.values()
defer.returnValue(state_delta)