diff --git a/synapse/rest/admin/__init__.py b/synapse/rest/admin/__init__.py
index 6f7dc06503..b80b036090 100644
--- a/synapse/rest/admin/__init__.py
+++ b/synapse/rest/admin/__init__.py
@@ -36,6 +36,7 @@ from synapse.rest.admin.media import ListMediaInRoom, register_servlets_for_medi
from synapse.rest.admin.purge_room_servlet import PurgeRoomServlet
from synapse.rest.admin.rooms import (
DeleteRoomRestServlet,
+ ForwardExtremitiesRestServlet,
JoinRoomAliasServlet,
ListRoomRestServlet,
MakeRoomAdminRestServlet,
@@ -230,6 +231,7 @@ def register_servlets(hs, http_server):
EventReportsRestServlet(hs).register(http_server)
PushersRestServlet(hs).register(http_server)
MakeRoomAdminRestServlet(hs).register(http_server)
+ ForwardExtremitiesRestServlet(hs).register(http_server)
def register_servlets_for_client_rest_resource(hs, http_server):
diff --git a/synapse/rest/admin/rooms.py b/synapse/rest/admin/rooms.py
index ab7cc9102a..6757a8100b 100644
--- a/synapse/rest/admin/rooms.py
+++ b/synapse/rest/admin/rooms.py
@@ -499,3 +499,60 @@ class MakeRoomAdminRestServlet(RestServlet):
)
return 200, {}
+
+
+class ForwardExtremitiesRestServlet(RestServlet):
+ """Allows a server admin to get or clear forward extremities.
+
+ Clearing does not require restarting the server.
+
+ Clear forward extremities:
+ DELETE /_synapse/admin/v1/rooms/<room_id_or_alias>/forward_extremities
+
+ Get forward_extremities:
+ GET /_synapse/admin/v1/rooms/<room_id_or_alias>/forward_extremities
+ """
+
+ PATTERNS = admin_patterns("/rooms/(?P<room_identifier>[^/]*)/forward_extremities")
+
+ def __init__(self, hs: "HomeServer"):
+ self.hs = hs
+ self.auth = hs.get_auth()
+ self.room_member_handler = hs.get_room_member_handler()
+ self.store = hs.get_datastore()
+
+ async def resolve_room_id(self, room_identifier: str) -> str:
+ """Resolve to a room ID, if necessary."""
+ if RoomID.is_valid(room_identifier):
+ resolved_room_id = room_identifier
+ elif RoomAlias.is_valid(room_identifier):
+ room_alias = RoomAlias.from_string(room_identifier)
+ room_id, _ = await self.room_member_handler.lookup_room_alias(room_alias)
+ resolved_room_id = room_id.to_string()
+ else:
+ raise SynapseError(
+ 400, "%s was not legal room ID or room alias" % (room_identifier,)
+ )
+ if not resolved_room_id:
+ raise SynapseError(
+ 400, "Unknown room ID or room alias %s" % room_identifier
+ )
+ return resolved_room_id
+
+ async def on_DELETE(self, request, room_identifier):
+ requester = await self.auth.get_user_by_req(request)
+ await assert_user_is_admin(self.auth, requester.user)
+
+ room_id = await self.resolve_room_id(room_identifier)
+
+ deleted_count = await self.store.delete_forward_extremities_for_room(room_id)
+ return 200, {"deleted": deleted_count}
+
+ async def on_GET(self, request, room_identifier):
+ requester = await self.auth.get_user_by_req(request)
+ await assert_user_is_admin(self.auth, requester.user)
+
+ room_id = await self.resolve_room_id(room_identifier)
+
+ extremities = await self.store.get_forward_extremities_for_room(room_id)
+ return 200, {"count": len(extremities), "results": extremities}
diff --git a/synapse/storage/databases/main/__init__.py b/synapse/storage/databases/main/__init__.py
index c4de07a0a8..93b25af057 100644
--- a/synapse/storage/databases/main/__init__.py
+++ b/synapse/storage/databases/main/__init__.py
@@ -43,6 +43,7 @@ from .end_to_end_keys import EndToEndKeyStore
from .event_federation import EventFederationStore
from .event_push_actions import EventPushActionsStore
from .events_bg_updates import EventsBackgroundUpdatesStore
+from .events_forward_extremities import EventForwardExtremitiesStore
from .filtering import FilteringStore
from .group_server import GroupServerStore
from .keys import KeyStore
@@ -118,6 +119,7 @@ class DataStore(
UIAuthStore,
CacheInvalidationWorkerStore,
ServerMetricsStore,
+ EventForwardExtremitiesStore,
):
def __init__(self, database: DatabasePool, db_conn, hs):
self.hs = hs
diff --git a/synapse/storage/databases/main/events_forward_extremities.py b/synapse/storage/databases/main/events_forward_extremities.py
new file mode 100644
index 0000000000..6b8da52fee
--- /dev/null
+++ b/synapse/storage/databases/main/events_forward_extremities.py
@@ -0,0 +1,92 @@
+import logging
+from typing import Dict, List
+
+from synapse.api.errors import SynapseError
+from synapse.storage._base import SQLBaseStore
+
+logger = logging.getLogger(__name__)
+
+
+class EventForwardExtremitiesStore(SQLBaseStore):
+ async def delete_forward_extremities_for_room(self, room_id: str) -> int:
+ """Delete any extra forward extremities for a room.
+
+ Invalidates the "get_latest_event_ids_in_room" cache if any forward
+ extremities were deleted.
+
+ Returns count deleted.
+ """
+
+ def delete_forward_extremities_for_room_txn(txn):
+ # First we need to get the event_id to not delete
+ sql = (
+ "SELECT "
+ " last_value(event_id) OVER w AS event_id"
+ " FROM event_forward_extremities"
+ " NATURAL JOIN events"
+ " where room_id = ?"
+ " WINDOW w AS ("
+ " PARTITION BY room_id"
+ " ORDER BY stream_ordering"
+ " range between unbounded preceding and unbounded following"
+ " )"
+ " ORDER BY stream_ordering"
+ )
+ txn.execute(sql, (room_id,))
+ rows = txn.fetchall()
+ try:
+ event_id = rows[0][0]
+ logger.debug(
+ "Found event_id %s as the forward extremity to keep for room %s",
+ event_id,
+ room_id,
+ )
+ except KeyError:
+ msg = f"No forward extremity event found for room {room_id}"
+ logger.warning(msg)
+ raise SynapseError(400, msg)
+
+ # Now delete the extra forward extremities
+ sql = (
+ "DELETE FROM event_forward_extremities "
+ "WHERE"
+ " event_id != ?"
+ " AND room_id = ?"
+ )
+
+ txn.execute(sql, (event_id, room_id))
+ logger.info(
+ "Deleted %s extra forward extremities for room %s",
+ txn.rowcount,
+ room_id,
+ )
+
+ if txn.rowcount > 0:
+ # Invalidate the cache
+ self._invalidate_cache_and_stream(
+ txn, self.get_latest_event_ids_in_room, (room_id,),
+ )
+
+ return txn.rowcount
+
+ return await self.db_pool.runInteraction(
+ "delete_forward_extremities_for_room",
+ delete_forward_extremities_for_room_txn,
+ )
+
+ async def get_forward_extremities_for_room(self, room_id: str) -> List[Dict]:
+ """Get list of forward extremities for a room."""
+
+ def get_forward_extremities_for_room_txn(txn):
+ sql = (
+ "SELECT event_id, state_group FROM event_forward_extremities NATURAL JOIN event_to_state_groups "
+ "WHERE room_id = ?"
+ )
+
+ txn.execute(sql, (room_id,))
+ rows = txn.fetchall()
+ return [{"event_id": row[0], "state_group": row[1]} for row in rows]
+
+ return await self.db_pool.runInteraction(
+ "get_forward_extremities_for_room", get_forward_extremities_for_room_txn,
+ )
|
