Convert additional database code to async/await. (#8195)

11 files changed, 246 insertions, 175 deletions

diff --git a/changelog.d/8195.misc b/changelog.d/8195.misc
new file mode 100644
index 0000000000..dfe4c03171
--- /dev/null
+++ b/changelog.d/8195.misc
@@ -0,0 +1 @@
+Convert various parts of the codebase to async/await.
diff --git a/synapse/appservice/__init__.py b/synapse/appservice/__init__.py
index 1ffdc1ed95..69a7182ef4 100644
--- a/synapse/appservice/__init__.py
+++ b/synapse/appservice/__init__.py
@@ -14,11 +14,16 @@
 # limitations under the License.
 import logging
 import re
+from typing import TYPE_CHECKING
 
 from synapse.api.constants import EventTypes
+from synapse.appservice.api import ApplicationServiceApi
 from synapse.types import GroupID, get_domain_from_id
 from synapse.util.caches.descriptors import cached
 
+if TYPE_CHECKING:
+    from synapse.storage.databases.main import DataStore
+
 logger = logging.getLogger(__name__)
 
 
@@ -35,19 +40,19 @@ class AppServiceTransaction(object):
         self.id = id
         self.events = events
 
-    def send(self, as_api):
+    async def send(self, as_api: ApplicationServiceApi) -> bool:
         """Sends this transaction using the provided AS API interface.
 
         Args:
-            as_api(ApplicationServiceApi): The API to use to send.
+            as_api: The API to use to send.
         Returns:
-            An Awaitable which resolves to True if the transaction was sent.
+            True if the transaction was sent.
         """
-        return as_api.push_bulk(
+        return await as_api.push_bulk(
             service=self.service, events=self.events, txn_id=self.id
         )
 
-    def complete(self, store):
+    async def complete(self, store: "DataStore") -> None:
         """Completes this transaction as successful.
 
         Marks this transaction ID on the application service and removes the
@@ -55,10 +60,8 @@ class AppServiceTransaction(object):
 
         Args:
             store: The database store to operate on.
-        Returns:
-            A Deferred which resolves to True if the transaction was completed.
         """
-        return store.complete_appservice_txn(service=self.service, txn_id=self.id)
+        await store.complete_appservice_txn(service=self.service, txn_id=self.id)
 
 
 class ApplicationService(object):
diff --git a/synapse/federation/persistence.py b/synapse/federation/persistence.py
index 769cd5de28..de1fe7da38 100644
--- a/synapse/federation/persistence.py
+++ b/synapse/federation/persistence.py
@@ -20,6 +20,7 @@ These actions are mostly only used by the :py:mod:`.replication` module.
 """
 
 import logging
+from typing import Optional, Tuple
 
 from synapse.federation.units import Transaction
 from synapse.logging.utils import log_function
@@ -36,25 +37,27 @@ class TransactionActions(object):
         self.store = datastore
 
     @log_function
-    def have_responded(self, origin, transaction):
-        """ Have we already responded to a transaction with the same id and
+    async def have_responded(
+        self, origin: str, transaction: Transaction
+    ) -> Optional[Tuple[int, JsonDict]]:
+        """Have we already responded to a transaction with the same id and
         origin?
 
         Returns:
-            Deferred: Results in `None` if we have not previously responded to
-            this transaction or a 2-tuple of `(int, dict)` representing the
-            response code and response body.
+            `None` if we have not previously responded to this transaction or a
+            2-tuple of `(int, dict)` representing the response code and response body.
         """
-        if not transaction.transaction_id:
+        transaction_id = transaction.transaction_id  # type: ignore
+        if not transaction_id:
             raise RuntimeError("Cannot persist a transaction with no transaction_id")
 
-        return self.store.get_received_txn_response(transaction.transaction_id, origin)
+        return await self.store.get_received_txn_response(transaction_id, origin)
 
     @log_function
     async def set_response(
         self, origin: str, transaction: Transaction, code: int, response: JsonDict
     ) -> None:
-        """ Persist how we responded to a transaction.
+        """Persist how we responded to a transaction.
         """
         transaction_id = transaction.transaction_id  # type: ignore
         if not transaction_id:
diff --git a/synapse/handlers/federation.py b/synapse/handlers/federation.py
index 155d087413..16389a0dca 100644
--- a/synapse/handlers/federation.py
+++ b/synapse/handlers/federation.py
@@ -1879,8 +1879,8 @@ class FederationHandler(BaseHandler):
         else:
             return None
 
-    def get_min_depth_for_context(self, context):
-        return self.store.get_min_depth(context)
+    async def get_min_depth_for_context(self, context):
+        return await self.store.get_min_depth(context)
 
     async def _handle_new_event(
         self, origin, event, state=None, auth_events=None, backfilled=False
diff --git a/synapse/storage/databases/main/appservice.py b/synapse/storage/databases/main/appservice.py
index 92f56f1602..454c0bc50c 100644
--- a/synapse/storage/databases/main/appservice.py
+++ b/synapse/storage/databases/main/appservice.py
@@ -172,7 +172,7 @@ class ApplicationServiceTransactionWorkerStore(
             "application_services_state", {"as_id": service.id}, {"state": state}
         )
 
-    def create_appservice_txn(self, service, events):
+    async def create_appservice_txn(self, service, events):
         """Atomically creates a new transaction for this application service
         with the given list of events.
 
@@ -209,20 +209,17 @@ class ApplicationServiceTransactionWorkerStore(
             )
             return AppServiceTransaction(service=service, id=new_txn_id, events=events)
 
-        return self.db_pool.runInteraction(
+        return await self.db_pool.runInteraction(
             "create_appservice_txn", _create_appservice_txn
         )
 
-    def complete_appservice_txn(self, txn_id, service):
+    async def complete_appservice_txn(self, txn_id, service) -> None:
         """Completes an application service transaction.
 
         Args:
             txn_id(str): The transaction ID being completed.
             service(ApplicationService): The application service which was sent
             this transaction.
-        Returns:
-            A Deferred which resolves if this transaction was stored
-            successfully.
         """
         txn_id = int(txn_id)
 
@@ -258,7 +255,7 @@ class ApplicationServiceTransactionWorkerStore(
                 {"txn_id": txn_id, "as_id": service.id},
             )
 
-        return self.db_pool.runInteraction(
+        await self.db_pool.runInteraction(
             "complete_appservice_txn", _complete_appservice_txn
         )
 
@@ -312,13 +309,13 @@ class ApplicationServiceTransactionWorkerStore(
         else:
             return int(last_txn_id[0])  # select 'last_txn' col
 
-    def set_appservice_last_pos(self, pos):
+    async def set_appservice_last_pos(self, pos) -> None:
         def set_appservice_last_pos_txn(txn):
             txn.execute(
                 "UPDATE appservice_stream_position SET stream_ordering = ?", (pos,)
             )
 
-        return self.db_pool.runInteraction(
+        await self.db_pool.runInteraction(
             "set_appservice_last_pos", set_appservice_last_pos_txn
         )
 
diff --git a/synapse/storage/databases/main/deviceinbox.py b/synapse/storage/databases/main/deviceinbox.py
index bb85637a95..0044433110 100644
--- a/synapse/storage/databases/main/deviceinbox.py
+++ b/synapse/storage/databases/main/deviceinbox.py
@@ -190,15 +190,15 @@ class DeviceInboxWorkerStore(SQLBaseStore):
         )
 
     @trace
-    def delete_device_msgs_for_remote(self, destination, up_to_stream_id):
+    async def delete_device_msgs_for_remote(
+        self, destination: str, up_to_stream_id: int
+    ) -> None:
         """Used to delete messages when the remote destination acknowledges
         their receipt.
 
         Args:
-            destination(str): The destination server_name
-            up_to_stream_id(int): Where to delete messages up to.
-        Returns:
-            A deferred that resolves when the messages have been deleted.
+            destination: The destination server_name
+            up_to_stream_id: Where to delete messages up to.
         """
 
         def delete_messages_for_remote_destination_txn(txn):
@@ -209,7 +209,7 @@ class DeviceInboxWorkerStore(SQLBaseStore):
             )
             txn.execute(sql, (destination, up_to_stream_id))
 
-        return self.db_pool.runInteraction(
+        await self.db_pool.runInteraction(
             "delete_device_msgs_for_remote", delete_messages_for_remote_destination_txn
         )
 
diff --git a/synapse/storage/databases/main/e2e_room_keys.py b/synapse/storage/databases/main/e2e_room_keys.py
index 82f9d870fd..12cecceec2 100644
--- a/synapse/storage/databases/main/e2e_room_keys.py
+++ b/synapse/storage/databases/main/e2e_room_keys.py
@@ -151,7 +151,7 @@ class EndToEndRoomKeyStore(SQLBaseStore):
 
         return sessions
 
-    def get_e2e_room_keys_multi(self, user_id, version, room_keys):
+    async def get_e2e_room_keys_multi(self, user_id, version, room_keys):
         """Get multiple room keys at a time.  The difference between this function and
         get_e2e_room_keys is that this function can be used to retrieve
         multiple specific keys at a time, whereas get_e2e_room_keys is used for
@@ -166,10 +166,10 @@ class EndToEndRoomKeyStore(SQLBaseStore):
                 that we want to query
 
         Returns:
-           Deferred[dict[str, dict[str, dict]]]: a map of room IDs to session IDs to room key
+           dict[str, dict[str, dict]]: a map of room IDs to session IDs to room key
         """
 
-        return self.db_pool.runInteraction(
+        return await self.db_pool.runInteraction(
             "get_e2e_room_keys_multi",
             self._get_e2e_room_keys_multi_txn,
             user_id,
@@ -283,7 +283,7 @@ class EndToEndRoomKeyStore(SQLBaseStore):
             raise StoreError(404, "No current backup version")
         return row[0]
 
-    def get_e2e_room_keys_version_info(self, user_id, version=None):
+    async def get_e2e_room_keys_version_info(self, user_id, version=None):
         """Get info metadata about a version of our room_keys backup.
 
         Args:
@@ -293,7 +293,7 @@ class EndToEndRoomKeyStore(SQLBaseStore):
         Raises:
             StoreError: with code 404 if there are no e2e_room_keys_versions present
         Returns:
-            A deferred dict giving the info metadata for this backup version, with
+            A dict giving the info metadata for this backup version, with
             fields including:
                 version(str)
                 algorithm(str)
@@ -324,12 +324,12 @@ class EndToEndRoomKeyStore(SQLBaseStore):
                 result["etag"] = 0
             return result
 
-        return self.db_pool.runInteraction(
+        return await self.db_pool.runInteraction(
             "get_e2e_room_keys_version_info", _get_e2e_room_keys_version_info_txn
         )
 
     @trace
-    def create_e2e_room_keys_version(self, user_id, info):
+    async def create_e2e_room_keys_version(self, user_id: str, info: dict) -> str:
         """Atomically creates a new version of this user's e2e_room_keys store
         with the given version info.
 
@@ -338,7 +338,7 @@ class EndToEndRoomKeyStore(SQLBaseStore):
             info(dict): the info about the backup version to be created
 
         Returns:
-            A deferred string for the newly created version ID
+            The newly created version ID
         """
 
         def _create_e2e_room_keys_version_txn(txn):
@@ -365,7 +365,7 @@ class EndToEndRoomKeyStore(SQLBaseStore):
 
             return new_version
 
-        return self.db_pool.runInteraction(
+        return await self.db_pool.runInteraction(
             "create_e2e_room_keys_version_txn", _create_e2e_room_keys_version_txn
         )
 
@@ -403,13 +403,15 @@ class EndToEndRoomKeyStore(SQLBaseStore):
             )
 
     @trace
-    def delete_e2e_room_keys_version(self, user_id, version=None):
+    async def delete_e2e_room_keys_version(
+        self, user_id: str, version: Optional[str] = None
+    ) -> None:
         """Delete a given backup version of the user's room keys.
         Doesn't delete their actual key data.
 
         Args:
-            user_id(str): the user whose backup version we're deleting
-            version(str): Optional. the version ID of the backup version we're deleting
+            user_id: the user whose backup version we're deleting
+            version: Optional. the version ID of the backup version we're deleting
                 If missing, we delete the current backup version info.
         Raises:
             StoreError: with code 404 if there are no e2e_room_keys_versions present,
@@ -430,13 +432,13 @@ class EndToEndRoomKeyStore(SQLBaseStore):
                 keyvalues={"user_id": user_id, "version": this_version},
             )
 
-            return self.db_pool.simple_update_one_txn(
+            self.db_pool.simple_update_one_txn(
                 txn,
                 table="e2e_room_keys_versions",
                 keyvalues={"user_id": user_id, "version": this_version},
                 updatevalues={"deleted": 1},
             )
 
-        return self.db_pool.runInteraction(
+        await self.db_pool.runInteraction(
             "delete_e2e_room_keys_version", _delete_e2e_room_keys_version_txn
         )
diff --git a/synapse/storage/databases/main/event_federation.py b/synapse/storage/databases/main/event_federation.py
index 6e5761c7b7..0b69aa6a94 100644
--- a/synapse/storage/databases/main/event_federation.py
+++ b/synapse/storage/databases/main/event_federation.py
@@ -59,7 +59,7 @@ class EventFederationWorkerStore(EventsWorkerStore, SignatureWorkerStore, SQLBas
             include_given: include the given events in result
 
         Returns:
-            list of event_ids
+            An awaitable which resolve to a list of event_ids
         """
         return await self.db_pool.runInteraction(
             "get_auth_chain_ids",
@@ -95,7 +95,7 @@ class EventFederationWorkerStore(EventsWorkerStore, SignatureWorkerStore, SQLBas
 
         return list(results)
 
-    def get_auth_chain_difference(self, state_sets: List[Set[str]]):
+    async def get_auth_chain_difference(self, state_sets: List[Set[str]]) -> Set[str]:
         """Given sets of state events figure out the auth chain difference (as
         per state res v2 algorithm).
 
@@ -104,10 +104,10 @@ class EventFederationWorkerStore(EventsWorkerStore, SignatureWorkerStore, SQLBas
         chain.
 
         Returns:
-            Deferred[Set[str]]
+            The set of the difference in auth chains.
         """
 
-        return self.db_pool.runInteraction(
+        return await self.db_pool.runInteraction(
             "get_auth_chain_difference",
             self._get_auth_chain_difference_txn,
             state_sets,
@@ -252,8 +252,8 @@ class EventFederationWorkerStore(EventsWorkerStore, SignatureWorkerStore, SQLBas
         # Return all events where not all sets can reach them.
         return {eid for eid, n in event_to_missing_sets.items() if n}
 
-    def get_oldest_events_with_depth_in_room(self, room_id):
-        return self.db_pool.runInteraction(
+    async def get_oldest_events_with_depth_in_room(self, room_id):
+        return await self.db_pool.runInteraction(
             "get_oldest_events_with_depth_in_room",
             self.get_oldest_events_with_depth_in_room_txn,
             room_id,
@@ -293,7 +293,7 @@ class EventFederationWorkerStore(EventsWorkerStore, SignatureWorkerStore, SQLBas
         else:
             return max(row["depth"] for row in rows)
 
-    def get_prev_events_for_room(self, room_id: str):
+    async def get_prev_events_for_room(self, room_id: str) -> List[str]:
         """
         Gets a subset of the current forward extremities in the given room.
 
@@ -301,14 +301,14 @@ class EventFederationWorkerStore(EventsWorkerStore, SignatureWorkerStore, SQLBas
         events which refer to hundreds of prev_events.
 
         Args:
-            room_id (str): room_id
+            room_id: room_id
 
         Returns:
-            Deferred[List[str]]: the event ids of the forward extremites
+            The event ids of the forward extremities.
 
         """
 
-        return self.db_pool.runInteraction(
+        return await self.db_pool.runInteraction(
             "get_prev_events_for_room", self._get_prev_events_for_room_txn, room_id
         )
 
@@ -328,17 +328,19 @@ class EventFederationWorkerStore(EventsWorkerStore, SignatureWorkerStore, SQLBas
 
         return [row[0] for row in txn]
 
-    def get_rooms_with_many_extremities(self, min_count, limit, room_id_filter):
+    async def get_rooms_with_many_extremities(
+        self, min_count: int, limit: int, room_id_filter: Iterable[str]
+    ) -> List[str]:
         """Get the top rooms with at least N extremities.
 
         Args:
-            min_count (int): The minimum number of extremities
-            limit (int): The maximum number of rooms to return.
-            room_id_filter (iterable[str]): room_ids to exclude from the results
+            min_count: The minimum number of extremities
+            limit: The maximum number of rooms to return.
+            room_id_filter: room_ids to exclude from the results
 
         Returns:
-            Deferred[list]: At most `limit` room IDs that have at least
-            `min_count` extremities, sorted by extremity count.
+            At most `limit` room IDs that have at least `min_count` extremities,
+            sorted by extremity count.
         """
 
         def _get_rooms_with_many_extremities_txn(txn):
@@ -363,7 +365,7 @@ class EventFederationWorkerStore(EventsWorkerStore, SignatureWorkerStore, SQLBas
             txn.execute(sql, query_args)
             return [room_id for room_id, in txn]
 
-        return self.db_pool.runInteraction(
+        return await self.db_pool.runInteraction(
             "get_rooms_with_many_extremities", _get_rooms_with_many_extremities_txn
         )
 
@@ -376,10 +378,10 @@ class EventFederationWorkerStore(EventsWorkerStore, SignatureWorkerStore, SQLBas
             desc="get_latest_event_ids_in_room",
         )
 
-    def get_min_depth(self, room_id):
-        """ For hte given room, get the minimum depth we have seen for it.
+    async def get_min_depth(self, room_id: str) -> int:
+        """For the given room, get the minimum depth we have seen for it.
         """
-        return self.db_pool.runInteraction(
+        return await self.db_pool.runInteraction(
             "get_min_depth", self._get_min_depth_interaction, room_id
         )
 
@@ -394,7 +396,9 @@ class EventFederationWorkerStore(EventsWorkerStore, SignatureWorkerStore, SQLBas
 
         return int(min_depth) if min_depth is not None else None
 
-    def get_forward_extremeties_for_room(self, room_id, stream_ordering):
+    async def get_forward_extremeties_for_room(
+        self, room_id: str, stream_ordering: int
+    ) -> List[str]:
         """For a given room_id and stream_ordering, return the forward
         extremeties of the room at that point in "time".
 
@@ -402,11 +406,11 @@ class EventFederationWorkerStore(EventsWorkerStore, SignatureWorkerStore, SQLBas
         stream_orderings from that point.
 
         Args:
-            room_id (str):
-            stream_ordering (int):
+            room_id:
+            stream_ordering:
 
         Returns:
-            deferred, which resolves to a list of event_ids
+            A list of event_ids
         """
         # We want to make the cache more effective, so we clamp to the last
         # change before the given ordering.
@@ -422,10 +426,10 @@ class EventFederationWorkerStore(EventsWorkerStore, SignatureWorkerStore, SQLBas
         if last_change > self.stream_ordering_month_ago:
             stream_ordering = min(last_change, stream_ordering)
 
-        return self._get_forward_extremeties_for_room(room_id, stream_ordering)
+        return await self._get_forward_extremeties_for_room(room_id, stream_ordering)
 
     @cached(max_entries=5000, num_args=2)
-    def _get_forward_extremeties_for_room(self, room_id, stream_ordering):
+    async def _get_forward_extremeties_for_room(self, room_id, stream_ordering):
         """For a given room_id and stream_ordering, return the forward
         extremeties of the room at that point in "time".
 
@@ -450,19 +454,18 @@ class EventFederationWorkerStore(EventsWorkerStore, SignatureWorkerStore, SQLBas
             txn.execute(sql, (stream_ordering, room_id))
             return [event_id for event_id, in txn]
 
-        return self.db_pool.runInteraction(
+        return await self.db_pool.runInteraction(
             "get_forward_extremeties_for_room", get_forward_extremeties_for_room_txn
         )
 
-    async def get_backfill_events(self, room_id, event_list, limit):
+    async def get_backfill_events(self, room_id: str, event_list: list, limit: int):
         """Get a list of Events for a given topic that occurred before (and
         including) the events in event_list. Return a list of max size `limit`
 
         Args:
-            txn
-            room_id (str)
-            event_list (list)
-            limit (int)
+            room_id
+            event_list
+            limit
         """
         event_ids = await self.db_pool.runInteraction(
             "get_backfill_events",
@@ -631,8 +634,8 @@ class EventFederationStore(EventFederationWorkerStore):
             _delete_old_forward_extrem_cache_txn,
         )
 
-    def clean_room_for_join(self, room_id):
-        return self.db_pool.runInteraction(
+    async def clean_room_for_join(self, room_id):
+        return await self.db_pool.runInteraction(
             "clean_room_for_join", self._clean_room_for_join_txn, room_id
         )
 
diff --git a/synapse/storage/databases/main/group_server.py b/synapse/storage/databases/main/group_server.py
index 6c60171888..ccfbb2135e 100644
--- a/synapse/storage/databases/main/group_server.py
+++ b/synapse/storage/databases/main/group_server.py
@@ -14,7 +14,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-from typing import Any, Dict, List, Optional, Tuple
+from typing import Any, Dict, List, Optional, Tuple, Union
 
 from synapse.api.errors import SynapseError
 from synapse.storage._base import SQLBaseStore, db_to_json
@@ -70,7 +70,9 @@ class GroupServerWorkerStore(SQLBaseStore):
             desc="get_invited_users_in_group",
         )
 
-    def get_rooms_in_group(self, group_id: str, include_private: bool = False):
+    async def get_rooms_in_group(
+        self, group_id: str, include_private: bool = False
+    ) -> List[Dict[str, Union[str, bool]]]:
         """Retrieve the rooms that belong to a given group. Does not return rooms that
         lack members.
 
@@ -79,8 +81,7 @@ class GroupServerWorkerStore(SQLBaseStore):
             include_private: Whether to return private rooms in results
 
         Returns:
-            Deferred[List[Dict[str, str|bool]]]: A list of dictionaries, each in the
-            form of:
+            A list of dictionaries, each in the form of:
 
             {
               "room_id": "!a_room_id:example.com",  # The ID of the room
@@ -117,13 +118,13 @@ class GroupServerWorkerStore(SQLBaseStore):
                 for room_id, is_public in txn
             ]
 
-        return self.db_pool.runInteraction(
+        return await self.db_pool.runInteraction(
             "get_rooms_in_group", _get_rooms_in_group_txn
         )
 
-    def get_rooms_for_summary_by_category(
+    async def get_rooms_for_summary_by_category(
         self, group_id: str, include_private: bool = False,
-    ):
+    ) -> Tuple[List[Dict[str, Any]], Dict[str, Any]]:
         """Get the rooms and categories that should be included in a summary request
 
         Args:
@@ -131,7 +132,7 @@ class GroupServerWorkerStore(SQLBaseStore):
             include_private: Whether to return private rooms in results
 
         Returns:
-            Deferred[Tuple[List, Dict]]: A tuple containing:
+            A tuple containing:
 
                 * A list of dictionaries with the keys:
                     * "room_id": str, the room ID
@@ -207,7 +208,7 @@ class GroupServerWorkerStore(SQLBaseStore):
 
             return rooms, categories
 
-        return self.db_pool.runInteraction(
+        return await self.db_pool.runInteraction(
             "get_rooms_for_summary", _get_rooms_for_summary_txn
         )
 
@@ -281,10 +282,11 @@ class GroupServerWorkerStore(SQLBaseStore):
             desc="get_local_groups_for_room",
         )
 
-    def get_users_for_summary_by_role(self, group_id, include_private=False):
+    async def get_users_for_summary_by_role(self, group_id, include_private=False):
         """Get the users and roles that should be included in a summary request
 
-        Returns ([users], [roles])
+        Returns:
+            ([users], [roles])
         """
 
         def _get_users_for_summary_txn(txn):
@@ -338,7 +340,7 @@ class GroupServerWorkerStore(SQLBaseStore):
 
             return users, roles
 
-        return self.db_pool.runInteraction(
+        return await self.db_pool.runInteraction(
             "get_users_for_summary_by_role", _get_users_for_summary_txn
         )
 
@@ -376,7 +378,7 @@ class GroupServerWorkerStore(SQLBaseStore):
             allow_none=True,
         )
 
-    def get_users_membership_info_in_group(self, group_id, user_id):
+    async def get_users_membership_info_in_group(self, group_id, user_id):
         """Get a dict describing the membership of a user in a group.
 
         Example if joined:
@@ -387,7 +389,8 @@ class GroupServerWorkerStore(SQLBaseStore):
                 "is_privileged": False,
             }
 
-        Returns an empty dict if the user is not join/invite/etc
+        Returns:
+             An empty dict if the user is not join/invite/etc
         """
 
         def _get_users_membership_in_group_txn(txn):
@@ -419,7 +422,7 @@ class GroupServerWorkerStore(SQLBaseStore):
 
             return {}
 
-        return self.db_pool.runInteraction(
+        return await self.db_pool.runInteraction(
             "get_users_membership_info_in_group", _get_users_membership_in_group_txn
         )
 
@@ -433,7 +436,7 @@ class GroupServerWorkerStore(SQLBaseStore):
             desc="get_publicised_groups_for_user",
         )
 
-    def get_attestations_need_renewals(self, valid_until_ms):
+    async def get_attestations_need_renewals(self, valid_until_ms):
         """Get all attestations that need to be renewed until givent time
         """
 
@@ -445,7 +448,7 @@ class GroupServerWorkerStore(SQLBaseStore):
             txn.execute(sql, (valid_until_ms,))
             return self.db_pool.cursor_to_dict(txn)
 
-        return self.db_pool.runInteraction(
+        return await self.db_pool.runInteraction(
             "get_attestations_need_renewals", _get_attestations_need_renewals_txn
         )
 
@@ -475,7 +478,7 @@ class GroupServerWorkerStore(SQLBaseStore):
             desc="get_joined_groups",
         )
 
-    def get_all_groups_for_user(self, user_id, now_token):
+    async def get_all_groups_for_user(self, user_id, now_token):
         def _get_all_groups_for_user_txn(txn):
             sql = """
                 SELECT group_id, type, membership, u.content
@@ -495,7 +498,7 @@ class GroupServerWorkerStore(SQLBaseStore):
                 for row in txn
             ]
 
-        return self.db_pool.runInteraction(
+        return await self.db_pool.runInteraction(
             "get_all_groups_for_user", _get_all_groups_for_user_txn
         )
 
@@ -600,8 +603,27 @@ class GroupServerStore(GroupServerWorkerStore):
             desc="set_group_join_policy",
         )
 
-    def add_room_to_summary(self, group_id, room_id, category_id, order, is_public):
-        return self.db_pool.runInteraction(
+    async def add_room_to_summary(
+        self,
+        group_id: str,
+        room_id: str,
+        category_id: str,
+        order: int,
+        is_public: Optional[bool],
+    ) -> None:
+        """Add (or update) room's entry in summary.
+
+        Args:
+            group_id
+            room_id
+            category_id: If not None then adds the category to the end of
+                the summary if its not already there.
+            order: If not None inserts the room at that position, e.g. an order
+                of 1 will put the room first. Otherwise, the room gets added to
+                the end.
+            is_public
+        """
+        await self.db_pool.runInteraction(
             "add_room_to_summary",
             self._add_room_to_summary_txn,
             group_id,
@@ -612,18 +634,26 @@ class GroupServerStore(GroupServerWorkerStore):
         )
 
     def _add_room_to_summary_txn(
-        self, txn, group_id, room_id, category_id, order, is_public
-    ):
+        self,
+        txn,
+        group_id: str,
+        room_id: str,
+        category_id: str,
+        order: int,
+        is_public: Optional[bool],
+    ) -> None:
         """Add (or update) room's entry in summary.
 
         Args:
-            group_id (str)
-            room_id (str)
-            category_id (str): If not None then adds the category to the end of
-                the summary if its not already there. [Optional]
-            order (int): If not None inserts the room at that position, e.g.
-                an order of 1 will put the room first. Otherwise, the room gets
-                added to the end.
+            txn
+            group_id
+            room_id
+            category_id: If not None then adds the category to the end of
+                the summary if its not already there.
+            order: If not None inserts the room at that position, e.g. an order
+                of 1 will put the room first. Otherwise, the room gets added to
+                the end.
+            is_public
         """
         room_in_group = self.db_pool.simple_select_one_onecol_txn(
             txn,
@@ -818,8 +848,27 @@ class GroupServerStore(GroupServerWorkerStore):
             desc="remove_group_role",
         )
 
-    def add_user_to_summary(self, group_id, user_id, role_id, order, is_public):
-        return self.db_pool.runInteraction(
+    async def add_user_to_summary(
+        self,
+        group_id: str,
+        user_id: str,
+        role_id: str,
+        order: int,
+        is_public: Optional[bool],
+    ) -> None:
+        """Add (or update) user's entry in summary.
+
+        Args:
+            group_id
+            user_id
+            role_id: If not None then adds the role to the end of the summary if
+                its not already there.
+            order: If not None inserts the user at that position, e.g. an order
+                of 1 will put the user first. Otherwise, the user gets added to
+                the end.
+            is_public
+        """
+        await self.db_pool.runInteraction(
             "add_user_to_summary",
             self._add_user_to_summary_txn,
             group_id,
@@ -830,18 +879,26 @@ class GroupServerStore(GroupServerWorkerStore):
         )
 
     def _add_user_to_summary_txn(
-        self, txn, group_id, user_id, role_id, order, is_public
+        self,
+        txn,
+        group_id: str,
+        user_id: str,
+        role_id: str,
+        order: int,
+        is_public: Optional[bool],
     ):
         """Add (or update) user's entry in summary.
 
         Args:
-            group_id (str)
-            user_id (str)
-            role_id (str): If not None then adds the role to the end of
-                the summary if its not already there. [Optional]
-            order (int): If not None inserts the user at that position, e.g.
-                an order of 1 will put the user first. Otherwise, the user gets
-                added to the end.
+            txn
+            group_id
+            user_id
+            role_id: If not None then adds the role to the end of the summary if
+                its not already there.
+            order: If not None inserts the user at that position, e.g. an order
+                of 1 will put the user first. Otherwise, the user gets added to
+                the end.
+            is_public
         """
         user_in_group = self.db_pool.simple_select_one_onecol_txn(
             txn,
@@ -963,27 +1020,26 @@ class GroupServerStore(GroupServerWorkerStore):
             desc="add_group_invite",
         )
 
-    def add_user_to_group(
+    async def add_user_to_group(
         self,
-        group_id,
-        user_id,
-        is_admin=False,
-        is_public=True,
-        local_attestation=None,
-        remote_attestation=None,
-    ):
+        group_id: str,
+        user_id: str,
+        is_admin: bool = False,
+        is_public: bool = True,
+        local_attestation: dict = None,
+        remote_attestation: dict = None,
+    ) -> None:
         """Add a user to the group server.
 
         Args:
-            group_id (str)
-            user_id (str)
-            is_admin (bool)
-            is_public (bool)
-            local_attestation (dict): The attestation the GS created to give
-                to the remote server. Optional if the user and group are on the
-                same server
-            remote_attestation (dict): The attestation given to GS by remote
+            group_id
+            user_id
+            is_admin
+            is_public
+            local_attestation: The attestation the GS created to give to the remote
                 server. Optional if the user and group are on the same server
+            remote_attestation: The attestation given to GS by remote server.
+                Optional if the user and group are on the same server
         """
 
         def _add_user_to_group_txn(txn):
@@ -1026,9 +1082,9 @@ class GroupServerStore(GroupServerWorkerStore):
                     },
                 )
 
-        return self.db_pool.runInteraction("add_user_to_group", _add_user_to_group_txn)
+        await self.db_pool.runInteraction("add_user_to_group", _add_user_to_group_txn)
 
-    def remove_user_from_group(self, group_id, user_id):
+    async def remove_user_from_group(self, group_id: str, user_id: str) -> None:
         def _remove_user_from_group_txn(txn):
             self.db_pool.simple_delete_txn(
                 txn,
@@ -1056,7 +1112,7 @@ class GroupServerStore(GroupServerWorkerStore):
                 keyvalues={"group_id": group_id, "user_id": user_id},
             )
 
-        return self.db_pool.runInteraction(
+        await self.db_pool.runInteraction(
             "remove_user_from_group", _remove_user_from_group_txn
         )
 
@@ -1079,7 +1135,7 @@ class GroupServerStore(GroupServerWorkerStore):
             desc="update_room_in_group_visibility",
         )
 
-    def remove_room_from_group(self, group_id, room_id):
+    async def remove_room_from_group(self, group_id: str, room_id: str) -> None:
         def _remove_room_from_group_txn(txn):
             self.db_pool.simple_delete_txn(
                 txn,
@@ -1093,7 +1149,7 @@ class GroupServerStore(GroupServerWorkerStore):
                 keyvalues={"group_id": group_id, "room_id": room_id},
             )
 
-        return self.db_pool.runInteraction(
+        await self.db_pool.runInteraction(
             "remove_room_from_group", _remove_room_from_group_txn
         )
 
@@ -1286,14 +1342,11 @@ class GroupServerStore(GroupServerWorkerStore):
     def get_group_stream_token(self):
         return self._group_updates_id_gen.get_current_token()
 
-    def delete_group(self, group_id):
+    async def delete_group(self, group_id: str) -> None:
         """Deletes a group fully from the database.
 
         Args:
-            group_id (str)
-
-        Returns:
-            Deferred
+            group_id: The group ID to delete.
         """
 
         def _delete_group_txn(txn):
@@ -1317,4 +1370,4 @@ class GroupServerStore(GroupServerWorkerStore):
                     txn, table=table, keyvalues={"group_id": group_id}
                 )
 
-        return self.db_pool.runInteraction("delete_group", _delete_group_txn)
+        await self.db_pool.runInteraction("delete_group", _delete_group_txn)
diff --git a/synapse/storage/databases/main/keys.py b/synapse/storage/databases/main/keys.py
index 1c0a049c55..ad43bb05ab 100644
--- a/synapse/storage/databases/main/keys.py
+++ b/synapse/storage/databases/main/keys.py
@@ -16,7 +16,7 @@
 
 import itertools
 import logging
-from typing import Iterable, Tuple
+from typing import Dict, Iterable, List, Optional, Tuple
 
 from signedjson.key import decode_verify_key_bytes
 
@@ -42,16 +42,17 @@ class KeyStore(SQLBaseStore):
     @cachedList(
         cached_method_name="_get_server_verify_key", list_name="server_name_and_key_ids"
     )
-    def get_server_verify_keys(self, server_name_and_key_ids):
+    async def get_server_verify_keys(
+        self, server_name_and_key_ids: Iterable[Tuple[str, str]]
+    ) -> Dict[Tuple[str, str], Optional[FetchKeyResult]]:
         """
         Args:
-            server_name_and_key_ids (iterable[Tuple[str, str]]):
+            server_name_and_key_ids:
                 iterable of (server_name, key-id) tuples to fetch keys for
 
         Returns:
-            Deferred: resolves to dict[Tuple[str, str], FetchKeyResult|None]:
-                map from (server_name, key_id) -> FetchKeyResult, or None if the key is
-                unknown
+            A map from (server_name, key_id) -> FetchKeyResult, or None if the
+            key is unknown
         """
         keys = {}
 
@@ -87,7 +88,7 @@ class KeyStore(SQLBaseStore):
                 _get_keys(txn, batch)
             return keys
 
-        return self.db_pool.runInteraction("get_server_verify_keys", _txn)
+        return await self.db_pool.runInteraction("get_server_verify_keys", _txn)
 
     async def store_server_verify_keys(
         self,
@@ -179,7 +180,9 @@ class KeyStore(SQLBaseStore):
             desc="store_server_keys_json",
         )
 
-    def get_server_keys_json(self, server_keys):
+    async def get_server_keys_json(
+        self, server_keys: Iterable[Tuple[str, Optional[str], Optional[str]]]
+    ) -> Dict[Tuple[str, Optional[str], Optional[str]], List[dict]]:
         """Retrive the key json for a list of server_keys and key ids.
         If no keys are found for a given server, key_id and source then
         that server, key_id, and source triplet entry will be an empty list.
@@ -188,8 +191,7 @@ class KeyStore(SQLBaseStore):
         Args:
             server_keys (list): List of (server_name, key_id, source) triplets.
         Returns:
-            Deferred[dict[Tuple[str, str, str|None], list[dict]]]:
-                Dict mapping (server_name, key_id, source) triplets to lists of dicts
+            A mapping from (server_name, key_id, source) triplets to a list of dicts
         """
 
         def _get_server_keys_json_txn(txn):
@@ -215,6 +217,6 @@ class KeyStore(SQLBaseStore):
                 results[(server_name, key_id, from_server)] = rows
             return results
 
-        return self.db_pool.runInteraction(
+        return await self.db_pool.runInteraction(
             "get_server_keys_json", _get_server_keys_json_txn
         )
diff --git a/synapse/storage/databases/main/transactions.py b/synapse/storage/databases/main/transactions.py
index 2efcc0dc66..5b31aab700 100644
--- a/synapse/storage/databases/main/transactions.py
+++ b/synapse/storage/databases/main/transactions.py
@@ -15,6 +15,7 @@
 
 import logging
 from collections import namedtuple
+from typing import Optional, Tuple
 
 from canonicaljson import encode_canonical_json
 
@@ -56,21 +57,23 @@ class TransactionStore(SQLBaseStore):
             expiry_ms=5 * 60 * 1000,
         )
 
-    def get_received_txn_response(self, transaction_id, origin):
+    async def get_received_txn_response(
+        self, transaction_id: str, origin: str
+    ) -> Optional[Tuple[int, JsonDict]]:
         """For an incoming transaction from a given origin, check if we have
         already responded to it. If so, return the response code and response
         body (as a dict).
 
         Args:
-            transaction_id (str)
-            origin(str)
+            transaction_id
+            origin
 
         Returns:
-            tuple: None if we have not previously responded to
-            this transaction or a 2-tuple of (int, dict)
+            None if we have not previously responded to this transaction or a
+            2-tuple of (int, dict)
         """
 
-        return self.db_pool.runInteraction(
+        return await self.db_pool.runInteraction(
             "get_received_txn_response",
             self._get_received_txn_response,
             transaction_id,
@@ -166,21 +169,25 @@ class TransactionStore(SQLBaseStore):
         else:
             return None
 
-    def set_destination_retry_timings(
-        self, destination, failure_ts, retry_last_ts, retry_interval
-    ):
+    async def set_destination_retry_timings(
+        self,
+        destination: str,
+        failure_ts: Optional[int],
+        retry_last_ts: int,
+        retry_interval: int,
+    ) -> None:
         """Sets the current retry timings for a given destination.
         Both timings should be zero if retrying is no longer occuring.
 
         Args:
-            destination (str)
-            failure_ts (int|None) - when the server started failing (ms since epoch)
-            retry_last_ts (int) - time of last retry attempt in unix epoch ms
-            retry_interval (int) - how long until next retry in ms
+            destination
+            failure_ts: when the server started failing (ms since epoch)
+            retry_last_ts: time of last retry attempt in unix epoch ms
+            retry_interval: how long until next retry in ms
         """
 
         self._destination_retry_cache.pop(destination, None)
-        return self.db_pool.runInteraction(
+        return await self.db_pool.runInteraction(
             "set_destination_retry_timings",
             self._set_destination_retry_timings,
             destination,
@@ -256,13 +263,13 @@ class TransactionStore(SQLBaseStore):
             "cleanup_transactions", self._cleanup_transactions
         )
 
-    def _cleanup_transactions(self):
+    async def _cleanup_transactions(self) -> None:
         now = self._clock.time_msec()
         month_ago = now - 30 * 24 * 60 * 60 * 1000
 
         def _cleanup_transactions_txn(txn):
             txn.execute("DELETE FROM received_transactions WHERE ts < ?", (month_ago,))
 
-        return self.db_pool.runInteraction(
+        await self.db_pool.runInteraction(
             "_cleanup_transactions", _cleanup_transactions_txn
         )