Convert presence handler helpers to async/await. (#7939)

changelog.d/7939.misc

@@ -0,0 +1 @@
+Convert presence handler helpers to async/await.

synapse/federation/sender/__init__.py

@@ -453,7 +453,9 @@ class FederationSender(object):
         """Given a list of states populate self.pending_presence_by_dest and
         poke to send a new transaction to each destination
         """
-        hosts_and_states = yield get_interested_remotes(self.store, states, self.state)
+        hosts_and_states = yield defer.ensureDeferred(
+            get_interested_remotes(self.store, states, self.state)
+        )
 
         for destinations, states in hosts_and_states:
             for destination in destinations:

synapse/handlers/presence.py

@@ -30,8 +30,6 @@ from typing import Dict, Iterable, List, Set, Tuple
 from prometheus_client import Counter
 from typing_extensions import ContextManager
 
-from twisted.internet import defer
-
 import synapse.metrics
 from synapse.api.constants import EventTypes, Membership, PresenceState
 from synapse.api.errors import SynapseError
@@ -39,6 +37,8 @@ from synapse.logging.context import run_in_background
 from synapse.logging.utils import log_function
 from synapse.metrics import LaterGauge
 from synapse.metrics.background_process_metrics import run_as_background_process
+from synapse.state import StateHandler
+from synapse.storage.data_stores.main import DataStore
 from synapse.storage.presence import UserPresenceState
 from synapse.types import JsonDict, UserID, get_domain_from_id
 from synapse.util.async_helpers import Linearizer
@@ -895,16 +895,9 @@ class PresenceHandler(BasePresenceHandler):
 
             await self._on_user_joined_room(room_id, state_key)
 
-    async def _on_user_joined_room(self, room_id, user_id):
+    async def _on_user_joined_room(self, room_id: str, user_id: str) -> None:
         """Called when we detect a user joining the room via the current state
         delta stream.
-
-        Args:
-            room_id (str)
-            user_id (str)
-
-        Returns:
-            Deferred
         """
 
         if self.is_mine_id(user_id):
@@ -1296,22 +1289,24 @@ def handle_update(prev_state, new_state, is_mine, wheel_timer, now):
     return new_state, persist_and_notify, federation_ping
 
 
-@defer.inlineCallbacks
+async def get_interested_parties(
-def get_interested_parties(store, states):
+    store: DataStore, 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:
-        states (list(UserPresenceState))
+        store
+        states
 
     Returns:
-        2-tuple: `(room_ids_to_states, users_to_states)`,
+        A 2-tuple of `(room_ids_to_states, users_to_states)`,
         with each item being a dict of `entity_name` -> `[UserPresenceState]`
     """
     room_ids_to_states = {}  # type: Dict[str, List[UserPresenceState]]
     users_to_states = {}  # type: Dict[str, List[UserPresenceState]]
     for state in states:
-        room_ids = yield store.get_rooms_for_user(state.user_id)
+        room_ids = await store.get_rooms_for_user(state.user_id)
         for room_id in room_ids:
             room_ids_to_states.setdefault(room_id, []).append(state)
 
@@ -1321,20 +1316,22 @@ def get_interested_parties(store, states):
     return room_ids_to_states, users_to_states
 
 
-@defer.inlineCallbacks
+async def get_interested_remotes(
-def get_interested_remotes(store, states, state_handler):
+    store: DataStore, states: List[UserPresenceState], state_handler: StateHandler
+) -> List[Tuple[List[str], List[UserPresenceState]]]:
     """Given a list of presence states figure out which remote servers
     should be sent which.
 
     All the presence states should be for local users only.
 
     Args:
-        store (DataStore)
+        store
-        states (list(UserPresenceState))
+        states
+        state_handler
 
     Returns:
-        Deferred list of ([destinations], [UserPresenceState]), where for
+        A list of 2-tuples of destinations and states, where for
-        each row the list of UserPresenceState should be sent to each
+        each tuple the list of UserPresenceState should be sent to each
         destination
     """
     hosts_and_states = []
@@ -1342,10 +1339,10 @@ def get_interested_remotes(store, states, state_handler):
     # 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 = yield get_interested_parties(store, states)
+    room_ids_to_states, users_to_states = await get_interested_parties(store, states)
 
     for room_id, states in room_ids_to_states.items():
-        hosts = yield state_handler.get_current_hosts_in_room(room_id)
+        hosts = await state_handler.get_current_hosts_in_room(room_id)
         hosts_and_states.append((hosts, states))
 
     for user_id, states in users_to_states.items():