Always use send_presence_to_destinations rather than send_presence

This a) reduces the API surface and b) means that we calculate where to
send presence on the presence writer, rather than federation senders.

3 files changed, 13 insertions, 119 deletions

diff --git a/synapse/federation/send_queue.py b/synapse/federation/send_queue.py
index e3f0bc2471..ba4e8e2d37 100644
--- a/synapse/federation/send_queue.py
+++ b/synapse/federation/send_queue.py
@@ -244,23 +244,6 @@ class FederationRemoteSendQueue(AbstractFederationSender):
         """
         # nothing to do here: the replication listener will handle it.
 
-    def send_presence(self, states: List[UserPresenceState]) -> None:
-        """As per FederationSender
-
-        Args:
-            states
-        """
-        pos = self._next_pos()
-
-        # We only want to send presence for our own users, so lets always just
-        # filter here just in case.
-        local_states = [s for s in states if self.is_mine_id(s.user_id)]
-
-        self.presence_map.update({state.user_id: state for state in local_states})
-        self.presence_changed[pos] = [state.user_id for state in local_states]
-
-        self.notifier.on_new_replication_data()
-
     def send_presence_to_destinations(
         self, states: Iterable[UserPresenceState], destinations: Iterable[str]
     ) -> None:
@@ -559,9 +542,6 @@ def process_rows_for_federation(
         parsed_row = RowType.from_data(row.data)
         parsed_row.add_to_buffer(buff)
 
-    if buff.presence:
-        transaction_queue.send_presence(buff.presence)
-
     for state, destinations in buff.presence_destinations:
         transaction_queue.send_presence_to_destinations(
             states=[state], destinations=destinations
diff --git a/synapse/federation/sender/__init__.py b/synapse/federation/sender/__init__.py
index 952ad39f8c..6266accaf5 100644
--- a/synapse/federation/sender/__init__.py
+++ b/synapse/federation/sender/__init__.py
@@ -24,8 +24,6 @@ from synapse.events import EventBase
 from synapse.federation.sender.per_destination_queue import PerDestinationQueue
 from synapse.federation.sender.transaction_manager import TransactionManager
 from synapse.federation.units import Edu
-from synapse.handlers.presence import get_interested_remotes
-from synapse.logging.context import preserve_fn
 from synapse.metrics import (
     LaterGauge,
     event_processing_loop_counter,
@@ -34,7 +32,7 @@ from synapse.metrics import (
 )
 from synapse.metrics.background_process_metrics import run_as_background_process
 from synapse.types import Collection, JsonDict, ReadReceipt, RoomStreamToken
-from synapse.util.metrics import Measure, measure_func
+from synapse.util.metrics import Measure
 
 if TYPE_CHECKING:
     from synapse.events.presence_router import PresenceRouter
@@ -80,15 +78,6 @@ class AbstractFederationSender(metaclass=abc.ABCMeta):
         raise NotImplementedError()
 
     @abc.abstractmethod
-    def send_presence(self, states: List[UserPresenceState]) -> None:
-        """Send the new presence states to the appropriate destinations.
-
-        This actually queues up the presence states ready for sending and
-        triggers a background task to process them and send out the transactions.
-        """
-        raise NotImplementedError()
-
-    @abc.abstractmethod
     def send_presence_to_destinations(
         self, states: Iterable[UserPresenceState], destinations: Iterable[str]
     ) -> None:
@@ -176,11 +165,6 @@ class FederationSender(AbstractFederationSender):
             ),
         )
 
-        # Map of user_id -> UserPresenceState for all the pending presence
-        # to be sent out by user_id. Entries here get processed and put in
-        # pending_presence_by_dest
-        self.pending_presence = {}  # type: Dict[str, UserPresenceState]
-
         LaterGauge(
             "synapse_federation_transaction_queue_pending_pdus",
             "",
@@ -201,8 +185,6 @@ class FederationSender(AbstractFederationSender):
         self._is_processing = False
         self._last_poked_id = -1
 
-        self._processing_pending_presence = False
-
         # map from room_id to a set of PerDestinationQueues which we believe are
         # awaiting a call to flush_read_receipts_for_room. The presence of an entry
         # here for a given room means that we are rate-limiting RR flushes to that room,
@@ -546,48 +528,6 @@ class FederationSender(AbstractFederationSender):
         for queue in queues:
             queue.flush_read_receipts_for_room(room_id)
 
-    @preserve_fn  # the caller should not yield on this
-    async def send_presence(self, states: List[UserPresenceState]) -> None:
-        """Send the new presence states to the appropriate destinations.
-
-        This actually queues up the presence states ready for sending and
-        triggers a background task to process them and send out the transactions.
-        """
-        if not self.hs.config.use_presence:
-            # No-op if presence is disabled.
-            return
-
-        # First we queue up the new presence by user ID, so multiple presence
-        # updates in quick succession are correctly handled.
-        # We only want to send presence for our own users, so lets always just
-        # filter here just in case.
-        self.pending_presence.update(
-            {state.user_id: state for state in states if self.is_mine_id(state.user_id)}
-        )
-
-        # We then handle the new pending presence in batches, first figuring
-        # out the destinations we need to send each state to and then poking it
-        # to attempt a new transaction. We linearize this so that we don't
-        # accidentally mess up the ordering and send multiple presence updates
-        # in the wrong order
-        if self._processing_pending_presence:
-            return
-
-        self._processing_pending_presence = True
-        try:
-            while True:
-                states_map = self.pending_presence
-                self.pending_presence = {}
-
-                if not states_map:
-                    break
-
-                await self._process_presence_inner(list(states_map.values()))
-        except Exception:
-            logger.exception("Error sending presence states to servers")
-        finally:
-            self._processing_pending_presence = False
-
     def send_presence_to_destinations(
         self, states: Iterable[UserPresenceState], destinations: Iterable[str]
     ) -> None:
@@ -608,40 +548,6 @@ class FederationSender(AbstractFederationSender):
                 continue
             self._get_per_destination_queue(destination).send_presence(states)
 
-    @measure_func("txnqueue._process_presence")
-    async def _process_presence_inner(self, states: List[UserPresenceState]) -> None:
-        """Given a list of states populate self.pending_presence_by_dest and
-        poke to send a new transaction to each destination
-        """
-        # We pull the presence router here instead of __init__
-        # to prevent a dependency cycle:
-        #
-        # AuthHandler -> Notifier -> FederationSender
-        # -> PresenceRouter -> ModuleApi -> AuthHandler
-        if self._presence_router is None:
-            self._presence_router = self.hs.get_presence_router()
-
-        assert self._presence_router is not None
-
-        hosts_and_states = await get_interested_remotes(
-            self.store,
-            self._presence_router,
-            states,
-            self.state,
-        )
-
-        for destinations, states in hosts_and_states:
-            for destination in destinations:
-                if destination == self.server_name:
-                    continue
-
-                if not self._federation_shard_config.should_handle(
-                    self._instance_name, destination
-                ):
-                    continue
-
-                self._get_per_destination_queue(destination).send_presence(states)
-
     def build_and_send_edu(
         self,
         destination: str,
diff --git a/synapse/handlers/presence.py b/synapse/handlers/presence.py
index e120dd1f48..a0cc779869 100644
--- a/synapse/handlers/presence.py
+++ b/synapse/handlers/presence.py
@@ -680,7 +680,7 @@ class PresenceHandler(BasePresenceHandler):
             if to_federation_ping:
                 federation_presence_out_counter.inc(len(to_federation_ping))
 
-                self._push_to_remotes(to_federation_ping.values())
+                await self._push_to_remotes(to_federation_ping.values())
 
     async def _handle_timeouts(self):
         """Checks the presence of users that have timed out and updates as
@@ -920,15 +920,23 @@ class PresenceHandler(BasePresenceHandler):
             users=[UserID.from_string(u) for u in users_to_states],
         )
 
-        self._push_to_remotes(states)
+        await self._push_to_remotes(states)
 
-    def _push_to_remotes(self, states):
+    async def _push_to_remotes(self, states):
         """Sends state updates to remote servers.
 
         Args:
             states (list(UserPresenceState))
         """
-        self.federation.send_presence(states)
+        hosts_and_states = await get_interested_remotes(
+            self.store,
+            self.presence_router,
+            states,
+            self.state,
+        )
+
+        for destinations, states in hosts_and_states:
+            self.federation.send_presence_to_destinations(states, destinations)
 
     async def incoming_presence(self, origin, content):
         """Called when we receive a `m.presence` EDU from a remote server."""