diff options
Diffstat (limited to 'synapse/handlers')
| -rw-r--r-- | synapse/handlers/presence.py | 243 |
1 files changed, 223 insertions, 20 deletions
diff --git a/synapse/handlers/presence.py b/synapse/handlers/presence.py index bd2382193f..598466c9bd 100644 --- a/synapse/handlers/presence.py +++ b/synapse/handlers/presence.py @@ -24,6 +24,7 @@ The methods that define policy are: import abc import contextlib import logging +from bisect import bisect from contextlib import contextmanager from typing import ( TYPE_CHECKING, @@ -53,7 +54,9 @@ from synapse.replication.http.presence import ( ReplicationBumpPresenceActiveTime, ReplicationPresenceSetState, ) +from synapse.replication.http.streams import ReplicationGetStreamUpdates from synapse.replication.tcp.commands import ClearUserSyncsCommand +from synapse.replication.tcp.streams import PresenceFederationStream, PresenceStream from synapse.state import StateHandler from synapse.storage.databases.main import DataStore from synapse.types import Collection, JsonDict, UserID, get_domain_from_id @@ -128,10 +131,10 @@ class BasePresenceHandler(abc.ABC): self.is_mine_id = hs.is_mine_id self._federation = None - if hs.should_send_federation() or not hs.config.worker_app: + if hs.should_send_federation(): self._federation = hs.get_federation_sender() - self._send_federation = hs.should_send_federation() + self._federation_queue = PresenceFederationQueue(hs, self) self._busy_presence_enabled = hs.config.experimental.msc3026_enabled @@ -254,9 +257,17 @@ class BasePresenceHandler(abc.ABC): """ pass - async def process_replication_rows(self, token, rows): - """Process presence stream rows received over replication.""" - pass + async def process_replication_rows( + self, stream_name: str, instance_name: str, token: int, rows: list + ): + """Process streams received over replication.""" + await self._federation_queue.process_replication_rows( + stream_name, instance_name, token, rows + ) + + def get_federation_queue(self) -> "PresenceFederationQueue": + """Get the presence federation queue.""" + return self._federation_queue async def maybe_send_presence_to_interested_destinations( self, states: List[UserPresenceState] @@ -266,12 +277,9 @@ class BasePresenceHandler(abc.ABC): users. """ - if not self._send_federation: + if not self._federation: return - # If this worker sends federation we must have a FederationSender. - assert self._federation - states = [s for s in states if self.is_mine_id(s.user_id)] if not states: @@ -427,7 +435,14 @@ class WorkerPresenceHandler(BasePresenceHandler): # If this is a federation sender, notify about presence updates. await self.maybe_send_presence_to_interested_destinations(states) - async def process_replication_rows(self, token, rows): + async def process_replication_rows( + self, stream_name: str, instance_name: str, token: int, rows: list + ): + await super().process_replication_rows(stream_name, instance_name, token, rows) + + if stream_name != PresenceStream.NAME: + return + states = [ UserPresenceState( row.user_id, @@ -729,12 +744,10 @@ class PresenceHandler(BasePresenceHandler): self.state, ) - # Since this is master we know that we have a federation sender or - # queue, and so this will be defined. - assert self._federation - for destinations, states in hosts_and_states: - self._federation.send_presence_to_destinations(states, destinations) + self._federation_queue.send_presence_to_destinations( + states, destinations + ) async def _handle_timeouts(self): """Checks the presence of users that have timed out and updates as @@ -1213,13 +1226,9 @@ class PresenceHandler(BasePresenceHandler): user_presence_states ) - # Since this is master we know that we have a federation sender or - # queue, and so this will be defined. - assert self._federation - # Send out user presence updates for each destination for destination, user_state_set in presence_destinations.items(): - self._federation.send_presence_to_destinations( + self._federation_queue.send_presence_to_destinations( destinations=[destination], states=user_state_set ) @@ -1864,3 +1873,197 @@ async def get_interested_remotes( hosts_and_states.append(([host], states)) return hosts_and_states + + +class PresenceFederationQueue: + """Handles sending ad hoc presence updates over federation, which are *not* + due to state updates (that get handled via the presence stream), e.g. + federation pings and sending existing present states to newly joined hosts. + + Only the last N minutes will be queued, so if a federation sender instance + is down for longer then some updates will be dropped. This is OK as presence + is ephemeral, and so it will self correct eventually. + + On workers the class tracks the last received position of the stream from + replication, and handles querying for missed updates over HTTP replication, + c.f. `get_current_token` and `get_replication_rows`. + """ + + # How long to keep entries in the queue for. Workers that are down for + # longer than this duration will miss out on older updates. + _KEEP_ITEMS_IN_QUEUE_FOR_MS = 5 * 60 * 1000 + + # How often to check if we can expire entries from the queue. + _CLEAR_ITEMS_EVERY_MS = 60 * 1000 + + def __init__(self, hs: "HomeServer", presence_handler: BasePresenceHandler): + self._clock = hs.get_clock() + self._notifier = hs.get_notifier() + self._instance_name = hs.get_instance_name() + self._presence_handler = presence_handler + self._repl_client = ReplicationGetStreamUpdates.make_client(hs) + + # Should we keep a queue of recent presence updates? We only bother if + # another process may be handling federation sending. + self._queue_presence_updates = True + + # Whether this instance is a presence writer. + self._presence_writer = hs.config.worker.worker_app is None + + # The FederationSender instance, if this process sends federation traffic directly. + self._federation = None + + if hs.should_send_federation(): + self._federation = hs.get_federation_sender() + + # We don't bother queuing up presence states if only this instance + # is sending federation. + if hs.config.worker.federation_shard_config.instances == [ + self._instance_name + ]: + self._queue_presence_updates = False + + # The queue of recently queued updates as tuples of: `(timestamp, + # stream_id, destinations, user_ids)`. We don't store the full states + # for efficiency, and remote workers will already have the full states + # cached. + self._queue = [] # type: List[Tuple[int, int, Collection[str], Set[str]]] + + self._next_id = 1 + + # Map from instance name to current token + self._current_tokens = {} # type: Dict[str, int] + + if self._queue_presence_updates: + self._clock.looping_call(self._clear_queue, self._CLEAR_ITEMS_EVERY_MS) + + def _clear_queue(self): + """Clear out older entries from the queue.""" + clear_before = self._clock.time_msec() - self._KEEP_ITEMS_IN_QUEUE_FOR_MS + + # The queue is sorted by timestamp, so we can bisect to find the right + # place to purge before. Note that we are searching using a 1-tuple with + # the time, which does The Right Thing since the queue is a tuple where + # the first item is a timestamp. + index = bisect(self._queue, (clear_before,)) + self._queue = self._queue[index:] + + def send_presence_to_destinations( + self, states: Collection[UserPresenceState], destinations: Collection[str] + ) -> None: + """Send the presence states to the given destinations. + + Will forward to the local federation sender (if there is one) and queue + to send over replication (if there are other federation sender instances.). + + Must only be called on the master process. + """ + + # This should only be called on a presence writer. + assert self._presence_writer + + if self._federation: + self._federation.send_presence_to_destinations( + states=states, + destinations=destinations, + ) + + if not self._queue_presence_updates: + return + + now = self._clock.time_msec() + + stream_id = self._next_id + self._next_id += 1 + + self._queue.append((now, stream_id, destinations, {s.user_id for s in states})) + + self._notifier.notify_replication() + + def get_current_token(self, instance_name: str) -> int: + """Get the current position of the stream. + + On workers this returns the last stream ID received from replication. + """ + if instance_name == self._instance_name: + return self._next_id - 1 + else: + return self._current_tokens.get(instance_name, 0) + + async def get_replication_rows( + self, + instance_name: str, + from_token: int, + upto_token: int, + target_row_count: int, + ) -> Tuple[List[Tuple[int, Tuple[str, str]]], int, bool]: + """Get all the updates between the two tokens. + + We return rows in the form of `(destination, user_id)` to keep the size + of each row bounded (rather than returning the sets in a row). + + On workers this will query the master process via HTTP replication. + """ + if instance_name != self._instance_name: + # If not local we query over http replication from the master + result = await self._repl_client( + instance_name=instance_name, + stream_name=PresenceFederationStream.NAME, + from_token=from_token, + upto_token=upto_token, + ) + return result["updates"], result["upto_token"], result["limited"] + + # We can find the correct position in the queue by noting that there is + # exactly one entry per stream ID, and that the last entry has an ID of + # `self._next_id - 1`, so we can count backwards from the end. + # + # Since the start of the queue is periodically truncated we need to + # handle the case where `from_token` stream ID has already been dropped. + start_idx = max(from_token - self._next_id, -len(self._queue)) + + to_send = [] # type: List[Tuple[int, Tuple[str, str]]] + limited = False + new_id = upto_token + for _, stream_id, destinations, user_ids in self._queue[start_idx:]: + if stream_id > upto_token: + break + + new_id = stream_id + + to_send.extend( + (stream_id, (destination, user_id)) + for destination in destinations + for user_id in user_ids + ) + + if len(to_send) > target_row_count: + limited = True + break + + return to_send, new_id, limited + + async def process_replication_rows( + self, stream_name: str, instance_name: str, token: int, rows: list + ): + if stream_name != PresenceFederationStream.NAME: + return + + # We keep track of the current tokens (so that we can catch up with anything we missed after a disconnect) + self._current_tokens[instance_name] = token + + # If we're a federation sender we pull out the presence states to send + # and forward them on. + if not self._federation: + return + + hosts_to_users = {} # type: Dict[str, Set[str]] + for row in rows: + hosts_to_users.setdefault(row.destination, set()).add(row.user_id) + + for host, user_ids in hosts_to_users.items(): + states = await self._presence_handler.current_state_for_users(user_ids) + self._federation.send_presence_to_destinations( + states=states.values(), + destinations=[host], + ) |