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Diffstat (limited to 'synapse/handlers/sync.py')
| -rw-r--r-- | synapse/handlers/sync.py | 434 |
1 files changed, 434 insertions, 0 deletions
diff --git a/synapse/handlers/sync.py b/synapse/handlers/sync.py new file mode 100644 index 0000000000..962686f4bb --- /dev/null +++ b/synapse/handlers/sync.py @@ -0,0 +1,434 @@ +# -*- 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(): + 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_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_events = yield self.state_handler.get_current_state( + room_id + ) + + 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_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 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 + + 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=room_key, + ) + (room_key, _) = keys + loaded_recents = sync_config.filter.filter_room_events(events) + 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_events = yield self.state_handler.get_current_state( + room_id + ) + + 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: + state_delta = yield self.state_handler.get_current_state(room_id) + + defer.returnValue(state_delta) |