diff options
Diffstat (limited to 'synapse/handlers/presence.py')
| -rw-r--r-- | synapse/handlers/presence.py | 278 |
1 files changed, 235 insertions, 43 deletions
diff --git a/synapse/handlers/presence.py b/synapse/handlers/presence.py index da92feacc9..c817f2952d 100644 --- a/synapse/handlers/presence.py +++ b/synapse/handlers/presence.py @@ -25,7 +25,17 @@ The methods that define policy are: import abc import logging from contextlib import contextmanager -from typing import TYPE_CHECKING, Dict, Iterable, List, Set, Tuple +from typing import ( + TYPE_CHECKING, + Dict, + FrozenSet, + Iterable, + List, + Optional, + Set, + Tuple, + Union, +) from prometheus_client import Counter from typing_extensions import ContextManager @@ -34,6 +44,7 @@ import synapse.metrics from synapse.api.constants import EventTypes, Membership, PresenceState from synapse.api.errors import SynapseError from synapse.api.presence import UserPresenceState +from synapse.events.presence_router import PresenceRouter from synapse.logging.context import run_in_background from synapse.logging.utils import log_function from synapse.metrics import LaterGauge @@ -42,7 +53,7 @@ from synapse.state import StateHandler from synapse.storage.databases.main import DataStore from synapse.types import Collection, JsonDict, UserID, get_domain_from_id from synapse.util.async_helpers import Linearizer -from synapse.util.caches.descriptors import cached +from synapse.util.caches.descriptors import _CacheContext, cached from synapse.util.metrics import Measure from synapse.util.wheel_timer import WheelTimer @@ -209,6 +220,7 @@ class PresenceHandler(BasePresenceHandler): self.notifier = hs.get_notifier() self.federation = hs.get_federation_sender() self.state = hs.get_state_handler() + self.presence_router = hs.get_presence_router() self._presence_enabled = hs.config.use_presence federation_registry = hs.get_federation_registry() @@ -653,7 +665,7 @@ class PresenceHandler(BasePresenceHandler): """ stream_id, max_token = await self.store.update_presence(states) - parties = await get_interested_parties(self.store, states) + parties = await get_interested_parties(self.store, self.presence_router, states) room_ids_to_states, users_to_states = parties self.notifier.on_new_event( @@ -1041,7 +1053,12 @@ class PresenceEventSource: # # Presence -> Notifier -> PresenceEventSource -> Presence # + # Same with get_module_api, get_presence_router + # + # AuthHandler -> Notifier -> PresenceEventSource -> ModuleApi -> AuthHandler self.get_presence_handler = hs.get_presence_handler + self.get_module_api = hs.get_module_api + self.get_presence_router = hs.get_presence_router self.clock = hs.get_clock() self.store = hs.get_datastore() self.state = hs.get_state_handler() @@ -1055,7 +1072,7 @@ class PresenceEventSource: include_offline=True, explicit_room_id=None, **kwargs - ): + ) -> Tuple[List[UserPresenceState], int]: # The process for getting presence events are: # 1. Get the rooms the user is in. # 2. Get the list of user in the rooms. @@ -1068,7 +1085,17 @@ class PresenceEventSource: # We don't try and limit the presence updates by the current token, as # sending down the rare duplicate is not a concern. + user_id = user.to_string() + stream_change_cache = self.store.presence_stream_cache + with Measure(self.clock, "presence.get_new_events"): + if user_id in self.get_module_api()._send_full_presence_to_local_users: + # This user has been specified by a module to receive all current, online + # user presence. Removing from_key and setting include_offline to false + # will do effectively this. + from_key = None + include_offline = False + if from_key is not None: from_key = int(from_key) @@ -1091,59 +1118,209 @@ class PresenceEventSource: # doesn't return. C.f. #5503. return [], max_token - presence = self.get_presence_handler() - stream_change_cache = self.store.presence_stream_cache - + # Figure out which other users this user should receive updates for users_interested_in = await self._get_interested_in(user, explicit_room_id) - user_ids_changed = set() # type: Collection[str] - changed = None - if from_key: - changed = stream_change_cache.get_all_entities_changed(from_key) + # We have a set of users that we're interested in the presence of. We want to + # cross-reference that with the users that have actually changed their presence. - if changed is not None and len(changed) < 500: - assert isinstance(user_ids_changed, set) + # Check whether this user should see all user updates - # For small deltas, its quicker to get all changes and then - # work out if we share a room or they're in our presence list - get_updates_counter.labels("stream").inc() - for other_user_id in changed: - if other_user_id in users_interested_in: - user_ids_changed.add(other_user_id) - else: - # Too many possible updates. Find all users we can see and check - # if any of them have changed. - get_updates_counter.labels("full").inc() + if users_interested_in == PresenceRouter.ALL_USERS: + # Provide presence state for all users + presence_updates = await self._filter_all_presence_updates_for_user( + user_id, include_offline, from_key + ) - if from_key: - user_ids_changed = stream_change_cache.get_entities_changed( - users_interested_in, from_key + # Remove the user from the list of users to receive all presence + if user_id in self.get_module_api()._send_full_presence_to_local_users: + self.get_module_api()._send_full_presence_to_local_users.remove( + user_id ) + + return presence_updates, max_token + + # Make mypy happy. users_interested_in should now be a set + assert not isinstance(users_interested_in, str) + + # The set of users that we're interested in and that have had a presence update. + # We'll actually pull the presence updates for these users at the end. + interested_and_updated_users = ( + set() + ) # type: Union[Set[str], FrozenSet[str]] + + if from_key: + # First get all users that have had a presence update + updated_users = stream_change_cache.get_all_entities_changed(from_key) + + # Cross-reference users we're interested in with those that have had updates. + # Use a slightly-optimised method for processing smaller sets of updates. + if updated_users is not None and len(updated_users) < 500: + # For small deltas, it's quicker to get all changes and then + # cross-reference with the users we're interested in + get_updates_counter.labels("stream").inc() + for other_user_id in updated_users: + if other_user_id in users_interested_in: + # mypy thinks this variable could be a FrozenSet as it's possibly set + # to one in the `get_entities_changed` call below, and `add()` is not + # method on a FrozenSet. That doesn't affect us here though, as + # `interested_and_updated_users` is clearly a set() above. + interested_and_updated_users.add(other_user_id) # type: ignore else: - user_ids_changed = users_interested_in + # Too many possible updates. Find all users we can see and check + # if any of them have changed. + get_updates_counter.labels("full").inc() - updates = await presence.current_state_for_users(user_ids_changed) + interested_and_updated_users = ( + stream_change_cache.get_entities_changed( + users_interested_in, from_key + ) + ) + else: + # No from_key has been specified. Return the presence for all users + # this user is interested in + interested_and_updated_users = users_interested_in + + # Retrieve the current presence state for each user + users_to_state = await self.get_presence_handler().current_state_for_users( + interested_and_updated_users + ) + presence_updates = list(users_to_state.values()) - if include_offline: - return (list(updates.values()), max_token) + # Remove the user from the list of users to receive all presence + if user_id in self.get_module_api()._send_full_presence_to_local_users: + self.get_module_api()._send_full_presence_to_local_users.remove(user_id) + + if not include_offline: + # Filter out offline presence states + presence_updates = self._filter_offline_presence_state(presence_updates) + + return presence_updates, max_token + + async def _filter_all_presence_updates_for_user( + self, + user_id: str, + include_offline: bool, + from_key: Optional[int] = None, + ) -> List[UserPresenceState]: + """ + Computes the presence updates a user should receive. + + First pulls presence updates from the database. Then consults PresenceRouter + for whether any updates should be excluded by user ID. + + Args: + user_id: The User ID of the user to compute presence updates for. + include_offline: Whether to include offline presence states from the results. + from_key: The minimum stream ID of updates to pull from the database + before filtering. + + Returns: + A list of presence states for the given user to receive. + """ + if from_key: + # Only return updates since the last sync + updated_users = self.store.presence_stream_cache.get_all_entities_changed( + from_key + ) + if not updated_users: + updated_users = [] + + # Get the actual presence update for each change + users_to_state = await self.get_presence_handler().current_state_for_users( + updated_users + ) + presence_updates = list(users_to_state.values()) + + if not include_offline: + # Filter out offline states + presence_updates = self._filter_offline_presence_state(presence_updates) else: - return ( - [s for s in updates.values() if s.state != PresenceState.OFFLINE], - max_token, + users_to_state = await self.store.get_presence_for_all_users( + include_offline=include_offline ) + presence_updates = list(users_to_state.values()) + + # TODO: This feels wildly inefficient, and it's unfortunate we need to ask the + # module for information on a number of users when we then only take the info + # for a single user + + # Filter through the presence router + users_to_state_set = await self.get_presence_router().get_users_for_states( + presence_updates + ) + + # We only want the mapping for the syncing user + presence_updates = list(users_to_state_set[user_id]) + + # Return presence information for all users + return presence_updates + + def _filter_offline_presence_state( + self, presence_updates: Iterable[UserPresenceState] + ) -> List[UserPresenceState]: + """Given an iterable containing user presence updates, return a list with any offline + presence states removed. + + Args: + presence_updates: Presence states to filter + + Returns: + A new list with any offline presence states removed. + """ + return [ + update + for update in presence_updates + if update.state != PresenceState.OFFLINE + ] + def get_current_key(self): return self.store.get_current_presence_token() @cached(num_args=2, cache_context=True) - async def _get_interested_in(self, user, explicit_room_id, cache_context): + async def _get_interested_in( + self, + user: UserID, + explicit_room_id: Optional[str] = None, + cache_context: Optional[_CacheContext] = None, + ) -> Union[Set[str], str]: """Returns the set of users that the given user should see presence - updates for + updates for. + + Args: + user: The user to retrieve presence updates for. + explicit_room_id: The users that are in the room will be returned. + + Returns: + A set of user IDs to return presence updates for, or "ALL" to return all + known updates. """ user_id = user.to_string() users_interested_in = set() users_interested_in.add(user_id) # So that we receive our own presence + # cache_context isn't likely to ever be None due to the @cached decorator, + # but we can't have a non-optional argument after the optional argument + # explicit_room_id either. Assert cache_context is not None so we can use it + # without mypy complaining. + assert cache_context + + # Check with the presence router whether we should poll additional users for + # their presence information + additional_users = await self.get_presence_router().get_interested_users( + user.to_string() + ) + if additional_users == PresenceRouter.ALL_USERS: + # If the module requested that this user see the presence updates of *all* + # users, then simply return that instead of calculating what rooms this + # user shares + return PresenceRouter.ALL_USERS + + # Add the additional users from the router + users_interested_in.update(additional_users) + + # Find the users who share a room with this user users_who_share_room = await self.store.get_users_who_share_room_with_user( user_id, on_invalidate=cache_context.invalidate ) @@ -1314,14 +1491,15 @@ def handle_update(prev_state, new_state, is_mine, wheel_timer, now): async def get_interested_parties( - store: DataStore, states: List[UserPresenceState] + store: DataStore, presence_router: PresenceRouter, states: List[UserPresenceState] ) -> Tuple[Dict[str, List[UserPresenceState]], Dict[str, List[UserPresenceState]]]: """Given a list of states return which entities (rooms, users) are interested in the given states. Args: - store - states + store: The homeserver's data store. + presence_router: A module for augmenting the destinations for presence updates. + states: A list of incoming user presence updates. Returns: A 2-tuple of `(room_ids_to_states, users_to_states)`, @@ -1337,11 +1515,22 @@ async def get_interested_parties( # Always notify self users_to_states.setdefault(state.user_id, []).append(state) + # Ask a presence routing module for any additional parties if one + # is loaded. + router_users_to_states = await presence_router.get_users_for_states(states) + + # Update the dictionaries with additional destinations and state to send + for user_id, user_states in router_users_to_states.items(): + users_to_states.setdefault(user_id, []).extend(user_states) + return room_ids_to_states, users_to_states async def get_interested_remotes( - store: DataStore, states: List[UserPresenceState], state_handler: StateHandler + store: DataStore, + presence_router: PresenceRouter, + states: List[UserPresenceState], + state_handler: StateHandler, ) -> List[Tuple[Collection[str], List[UserPresenceState]]]: """Given a list of presence states figure out which remote servers should be sent which. @@ -1349,9 +1538,10 @@ async def get_interested_remotes( All the presence states should be for local users only. Args: - store - states - state_handler + store: The homeserver's data store. + presence_router: A module for augmenting the destinations for presence updates. + states: A list of incoming user presence updates. + state_handler: Returns: A list of 2-tuples of destinations and states, where for @@ -1363,7 +1553,9 @@ async def get_interested_remotes( # First we look up the rooms each user is in (as well as any explicit # subscriptions), then for each distinct room we look up the remote # hosts in those rooms. - room_ids_to_states, users_to_states = await get_interested_parties(store, states) + room_ids_to_states, users_to_states = await get_interested_parties( + store, presence_router, states + ) for room_id, states in room_ids_to_states.items(): hosts = await state_handler.get_current_hosts_in_room(room_id) |