diff options
Diffstat (limited to 'synapse/handlers/sliding_sync.py')
| -rw-r--r-- | synapse/handlers/sliding_sync.py | 350 |
1 files changed, 314 insertions, 36 deletions
diff --git a/synapse/handlers/sliding_sync.py b/synapse/handlers/sliding_sync.py index 3231574402..2b74f1c9c9 100644 --- a/synapse/handlers/sliding_sync.py +++ b/synapse/handlers/sliding_sync.py @@ -18,6 +18,7 @@ # # import logging +from enum import Enum from itertools import chain from typing import ( TYPE_CHECKING, @@ -34,6 +35,7 @@ from typing import ( import attr from immutabledict import immutabledict +from typing_extensions import assert_never from synapse.api.constants import AccountDataTypes, Direction, EventTypes, Membership from synapse.events import EventBase @@ -52,6 +54,7 @@ from synapse.types import ( RoomStreamToken, SlidingSyncStreamToken, StateMap, + StrCollection, StreamKeyType, StreamToken, UserID, @@ -361,6 +364,8 @@ class SlidingSyncHandler: self.push_rules_handler = hs.get_push_rules_handler() self.rooms_to_exclude_globally = hs.config.server.rooms_to_exclude_from_sync + self.connection_store = SlidingSyncConnectionStore() + async def wait_for_sync_for_user( self, requester: Requester, @@ -464,6 +469,11 @@ class SlidingSyncHandler: # See https://github.com/matrix-org/matrix-doc/issues/1144 raise NotImplementedError() + await self.connection_store.mark_token_seen( + sync_config=sync_config, + from_token=from_token, + ) + # Get all of the room IDs that the user should be able to see in the sync # response has_lists = sync_config.lists is not None and len(sync_config.lists) > 0 @@ -613,7 +623,7 @@ class SlidingSyncHandler: @tag_args async def handle_room(room_id: str) -> None: room_sync_result = await self.get_room_sync_data( - user=sync_config.user, + sync_config=sync_config, room_id=room_id, room_sync_config=relevant_room_map[room_id], room_membership_for_user_at_to_token=room_membership_for_user_map[ @@ -635,11 +645,22 @@ class SlidingSyncHandler: to_token=to_token, ) - # TODO: Update this when we implement per-connection state - connection_token = 0 + if has_lists or has_room_subscriptions: + connection_position = await self.connection_store.record_rooms( + sync_config=sync_config, + from_token=from_token, + sent_room_ids=relevant_room_map.keys(), + # TODO: We need to calculate which rooms have had updates since the `from_token` but were not included in the `sent_room_ids` + unsent_room_ids=[], + ) + elif from_token: + connection_position = from_token.connection_position + else: + # Initial sync without a `from_token` starts at `0` + connection_position = 0 return SlidingSyncResult( - next_pos=SlidingSyncStreamToken(to_token, connection_token), + next_pos=SlidingSyncStreamToken(to_token, connection_position), lists=lists, rooms=rooms, extensions=extensions, @@ -1370,7 +1391,7 @@ class SlidingSyncHandler: async def get_room_sync_data( self, - user: UserID, + sync_config: SlidingSyncConfig, room_id: str, room_sync_config: RoomSyncConfig, room_membership_for_user_at_to_token: _RoomMembershipForUser, @@ -1392,6 +1413,37 @@ class SlidingSyncHandler: from_token: The point in the stream to sync from. to_token: The point in the stream to sync up to. """ + user = sync_config.user + + # Determine whether we should limit the timeline to the token range. + # + # We should return historical messages (before token range) in the + # following cases because we want clients to be able to show a basic + # screen of information: + # - Initial sync (because no `from_token` to limit us anyway) + # - When users `newly_joined` + # - For an incremental sync where we haven't sent it down this + # connection before + from_bound = None + initial = True + if from_token and not room_membership_for_user_at_to_token.newly_joined: + room_status = await self.connection_store.have_sent_room( + sync_config=sync_config, + connection_token=from_token.connection_position, + room_id=room_id, + ) + if room_status.status == HaveSentRoomFlag.LIVE: + from_bound = from_token.stream_token.room_key + initial = False + elif room_status.status == HaveSentRoomFlag.PREVIOUSLY: + assert room_status.last_token is not None + from_bound = room_status.last_token + initial = False + elif room_status.status == HaveSentRoomFlag.NEVER: + from_bound = None + initial = True + else: + assert_never(room_status.status) # Assemble the list of timeline events # @@ -1418,36 +1470,23 @@ class SlidingSyncHandler: prev_batch_token = to_token # We're going to paginate backwards from the `to_token` - from_bound = to_token.room_key + to_bound = to_token.room_key # People shouldn't see past their leave/ban event if room_membership_for_user_at_to_token.membership in ( Membership.LEAVE, Membership.BAN, ): - from_bound = ( + to_bound = ( room_membership_for_user_at_to_token.event_pos.to_room_stream_token() ) - # Determine whether we should limit the timeline to the token range. - # - # We should return historical messages (before token range) in the - # following cases because we want clients to be able to show a basic - # screen of information: - # - Initial sync (because no `from_token` to limit us anyway) - # - When users `newly_joined` - # - TODO: For an incremental sync where we haven't sent it down this - # connection before - to_bound = ( - from_token.stream_token.room_key - if from_token is not None - and not room_membership_for_user_at_to_token.newly_joined - else None - ) - timeline_events, new_room_key = await self.store.paginate_room_events( room_id=room_id, - from_key=from_bound, - to_key=to_bound, + # The bounds are reversed so we can paginate backwards + # (from newer to older events) starting at to_bound. + # This ensures we fill the `limit` with the newest events first, + from_key=to_bound, + to_key=from_bound, direction=Direction.BACKWARDS, # We add one so we can determine if there are enough events to saturate # the limit or not (see `limited`) @@ -1564,12 +1603,6 @@ class SlidingSyncHandler: # indicate to the client that a state reset happened. Perhaps we should indicate # this by setting `initial: True` and empty `required_state`. - # TODO: Since we can't determine whether we've already sent a room down this - # Sliding Sync connection before (we plan to add this optimization in the - # future), we're always returning the requested room state instead of - # updates. - initial = True - # Check whether the room has a name set name_state_ids = await self.get_current_state_ids_at( room_id=room_id, @@ -1715,9 +1748,22 @@ class SlidingSyncHandler: to_token=to_token, ) else: - # TODO: Once we can figure out if we've sent a room down this connection before, - # we can return updates instead of the full required state. - raise NotImplementedError() + assert from_bound is not None + + # TODO: Limit the number of state events we're about to send down + # the room, if its too many we should change this to an + # `initial=True`? + deltas = await self.store.get_current_state_deltas_for_room( + room_id=room_id, + from_token=from_bound, + to_token=to_token.room_key, + ) + # TODO: Filter room state before fetching events + # TODO: Handle state resets where event_id is None + events = await self.store.get_events( + [d.event_id for d in deltas if d.event_id] + ) + room_state = {(s.type, s.state_key): s for s in events.values()} required_room_state: StateMap[EventBase] = {} if required_state_filter != StateFilter.none(): @@ -1863,7 +1909,7 @@ class SlidingSyncHandler: to_token: The point in the stream to sync up to. """ user_id = sync_config.user.to_string() - device_id = sync_config.device_id + device_id = sync_config.requester.device_id # Skip if the extension is not enabled if not to_device_request.enabled: @@ -1939,7 +1985,7 @@ class SlidingSyncHandler: from_token: The point in the stream to sync from. """ user_id = sync_config.user.to_string() - device_id = sync_config.device_id + device_id = sync_config.requester.device_id # Skip if the extension is not enabled if not e2ee_request.enabled: @@ -2094,3 +2140,235 @@ class SlidingSyncHandler: global_account_data_map=global_account_data_map, account_data_by_room_map=account_data_by_room_map, ) + + +class HaveSentRoomFlag(Enum): + """Flag for whether we have sent the room down a sliding sync connection. + + The valid state changes here are: + NEVER -> LIVE + LIVE -> PREVIOUSLY + PREVIOUSLY -> LIVE + """ + + # The room has never been sent down (or we have forgotten we have sent it + # down). + NEVER = 1 + + # We have previously sent the room down, but there are updates that we + # haven't sent down. + PREVIOUSLY = 2 + + # We have sent the room down and the client has received all updates. + LIVE = 3 + + +@attr.s(auto_attribs=True, slots=True, frozen=True) +class HaveSentRoom: + """Whether we have sent the room down a sliding sync connection. + + Attributes: + status: Flag of if we have or haven't sent down the room + last_token: If the flag is `PREVIOUSLY` then this is non-null and + contains the last stream token of the last updates we sent down + the room, i.e. we still need to send everything since then to the + client. + """ + + status: HaveSentRoomFlag + last_token: Optional[RoomStreamToken] + + @staticmethod + def previously(last_token: RoomStreamToken) -> "HaveSentRoom": + """Constructor for `PREVIOUSLY` flag.""" + return HaveSentRoom(HaveSentRoomFlag.PREVIOUSLY, last_token) + + +HAVE_SENT_ROOM_NEVER = HaveSentRoom(HaveSentRoomFlag.NEVER, None) +HAVE_SENT_ROOM_LIVE = HaveSentRoom(HaveSentRoomFlag.LIVE, None) + + +@attr.s(auto_attribs=True) +class SlidingSyncConnectionStore: + """In-memory store of per-connection state, including what rooms we have + previously sent down a sliding sync connection. + + Note: This is NOT safe to run in a worker setup because connection positions will + point to different sets of rooms on different workers. e.g. for the same connection, + a connection position of 5 might have totally different states on worker A and + worker B. + + One complication that we need to deal with here is needing to handle requests being + resent, i.e. if we sent down a room in a response that the client received, we must + consider the room *not* sent when we get the request again. + + This is handled by using an integer "token", which is returned to the client + as part of the sync token. For each connection we store a mapping from + tokens to the room states, and create a new entry when we send down new + rooms. + + Note that for any given sliding sync connection we will only store a maximum + of two different tokens: the previous token from the request and a new token + sent in the response. When we receive a request with a given token, we then + clear out all other entries with a different token. + + Attributes: + _connections: Mapping from `(user_id, conn_id)` to mapping of `token` + to mapping of room ID to `HaveSentRoom`. + """ + + # `(user_id, conn_id)` -> `token` -> `room_id` -> `HaveSentRoom` + _connections: Dict[Tuple[str, str], Dict[int, Dict[str, HaveSentRoom]]] = ( + attr.Factory(dict) + ) + + async def have_sent_room( + self, sync_config: SlidingSyncConfig, connection_token: int, room_id: str + ) -> HaveSentRoom: + """For the given user_id/conn_id/token, return whether we have + previously sent the room down + """ + + conn_key = self._get_connection_key(sync_config) + sync_statuses = self._connections.setdefault(conn_key, {}) + room_status = sync_statuses.get(connection_token, {}).get( + room_id, HAVE_SENT_ROOM_NEVER + ) + + return room_status + + async def record_rooms( + self, + sync_config: SlidingSyncConfig, + from_token: Optional[SlidingSyncStreamToken], + *, + sent_room_ids: StrCollection, + unsent_room_ids: StrCollection, + ) -> int: + """Record which rooms we have/haven't sent down in a new response + + Attributes: + sync_config + from_token: The since token from the request, if any + sent_room_ids: The set of room IDs that we have sent down as + part of this request (only needs to be ones we didn't + previously sent down). + unsent_room_ids: The set of room IDs that have had updates + since the `from_token`, but which were not included in + this request + """ + prev_connection_token = 0 + if from_token is not None: + prev_connection_token = from_token.connection_position + + # If there are no changes then this is a noop. + if not sent_room_ids and not unsent_room_ids: + return prev_connection_token + + conn_key = self._get_connection_key(sync_config) + sync_statuses = self._connections.setdefault(conn_key, {}) + + # Generate a new token, removing any existing entries in that token + # (which can happen if requests get resent). + new_store_token = prev_connection_token + 1 + sync_statuses.pop(new_store_token, None) + + # Copy over and update the room mappings. + new_room_statuses = dict(sync_statuses.get(prev_connection_token, {})) + + # Whether we have updated the `new_room_statuses`, if we don't by the + # end we can treat this as a noop. + have_updated = False + for room_id in sent_room_ids: + new_room_statuses[room_id] = HAVE_SENT_ROOM_LIVE + have_updated = True + + # Whether we add/update the entries for unsent rooms depends on the + # existing entry: + # - LIVE: We have previously sent down everything up to + # `last_room_token, so we update the entry to be `PREVIOUSLY` with + # `last_room_token`. + # - PREVIOUSLY: We have previously sent down everything up to *a* + # given token, so we don't need to update the entry. + # - NEVER: We have never previously sent down the room, and we haven't + # sent anything down this time either so we leave it as NEVER. + + # Work out the new state for unsent rooms that were `LIVE`. + if from_token: + new_unsent_state = HaveSentRoom.previously(from_token.stream_token.room_key) + else: + new_unsent_state = HAVE_SENT_ROOM_NEVER + + for room_id in unsent_room_ids: + prev_state = new_room_statuses.get(room_id) + if prev_state is not None and prev_state.status == HaveSentRoomFlag.LIVE: + new_room_statuses[room_id] = new_unsent_state + have_updated = True + + if not have_updated: + return prev_connection_token + + sync_statuses[new_store_token] = new_room_statuses + + return new_store_token + + async def mark_token_seen( + self, + sync_config: SlidingSyncConfig, + from_token: Optional[SlidingSyncStreamToken], + ) -> None: + """We have received a request with the given token, so we can clear out + any other tokens associated with the connection. + + If there is no from token then we have started afresh, and so we delete + all tokens associated with the device. + """ + # Clear out any tokens for the connection that doesn't match the one + # from the request. + + conn_key = self._get_connection_key(sync_config) + sync_statuses = self._connections.pop(conn_key, {}) + if from_token is None: + return + + sync_statuses = { + connection_token: room_statuses + for connection_token, room_statuses in sync_statuses.items() + if connection_token == from_token.connection_position + } + if sync_statuses: + self._connections[conn_key] = sync_statuses + + @staticmethod + def _get_connection_key(sync_config: SlidingSyncConfig) -> Tuple[str, str]: + """Return a unique identifier for this connection. + + The first part is simply the user ID. + + The second part is generally a combination of device ID and conn_id. + However, both these two are optional (e.g. puppet access tokens don't + have device IDs), so this handles those edge cases. + + We use this over the raw `conn_id` to avoid clashes between different + clients that use the same `conn_id`. Imagine a user uses a web client + that uses `conn_id: main_sync_loop` and an Android client that also has + a `conn_id: main_sync_loop`. + """ + + user_id = sync_config.user.to_string() + + # Only one sliding sync connection is allowed per given conn_id (empty + # or not). + conn_id = sync_config.conn_id or "" + + if sync_config.requester.device_id: + return (user_id, f"D/{sync_config.requester.device_id}/{conn_id}") + + if sync_config.requester.access_token_id: + # If we don't have a device, then the access token ID should be a + # stable ID. + return (user_id, f"A/{sync_config.requester.access_token_id}/{conn_id}") + + # If we have neither then its likely an AS or some weird token. Either + # way we can just fail here. + raise Exception("Cannot use sliding sync with access token type") |