Allow modules to delete rooms. (#15997)

* Allow user_id to be optional for room deletion

* Add module API method to delete a room

* Newsfile

Signed-off-by: Olivier Wilkinson (reivilibre) <oliverw@matrix.org>

* Don't worry about the case block=True && requester_user_id is None

---------

Signed-off-by: Olivier Wilkinson (reivilibre) <oliverw@matrix.org>

changelog.d/15997.misc

@@ -0,0 +1 @@
+Allow modules to delete rooms.

synapse/handlers/pagination.py

@@ -713,7 +713,7 @@ async def _shutdown_and_purge_room(
  self,
  delete_id: str,
  room_id: str,
- requester_user_id: str,
+ requester_user_id: Optional[str],
  new_room_user_id: Optional[str] = None,
  new_room_name: Optional[str] = None,
  message: Optional[str] = None,
@@ -732,6 +732,10 @@ async def _shutdown_and_purge_room(
  requester_user_id:
  User who requested the action. Will be recorded as putting the room on the
  blocking list.
+ If None, the action was not manually requested but instead
+ triggered automatically, e.g. through a Synapse module
+ or some other policy.
+ MUST NOT be None if block=True.
  new_room_user_id:
  If set, a new room will be created with this user ID
  as the creator and admin, and all users in the old room will be
@@ -818,7 +822,7 @@ def clear_delete() -> None:
  def start_shutdown_and_purge_room(
  self,
  room_id: str,
- requester_user_id: str,
+ requester_user_id: Optional[str],
  new_room_user_id: Optional[str] = None,
  new_room_name: Optional[str] = None,
  message: Optional[str] = None,
@@ -833,6 +837,10 @@ def start_shutdown_and_purge_room(
  requester_user_id:
  User who requested the action and put the room on the
  blocking list.
+ If None, the action was not manually requested but instead
+ triggered automatically, e.g. through a Synapse module
+ or some other policy.
+ MUST NOT be None if block=True.
  new_room_user_id:
  If set, a new room will be created with this user ID
  as the creator and admin, and all users in the old room will be

synapse/handlers/room.py

@@ -1787,7 +1787,7 @@ def __init__(self, hs: "HomeServer"):
  async def shutdown_room(
  self,
  room_id: str,
- requester_user_id: str,
+ requester_user_id: Optional[str],
  new_room_user_id: Optional[str] = None,
  new_room_name: Optional[str] = None,
  message: Optional[str] = None,
@@ -1811,6 +1811,10 @@ async def shutdown_room(
  requester_user_id:
  User who requested the action and put the room on the
  blocking list.
+ If None, the action was not manually requested but instead
+ triggered automatically, e.g. through a Synapse module
+ or some other policy.
+ MUST NOT be None if block=True.
  new_room_user_id:
  If set, a new room will be created with this user ID
  as the creator and admin, and all users in the old room will be
@@ -1863,6 +1867,10 @@ async def shutdown_room(
 
  # Action the block first (even if the room doesn't exist yet)
  if block:
+ if requester_user_id is None:
+ raise ValueError(
+ "shutdown_room: block=True not allowed when requester_user_id is None."
+ )
  # This will work even if the room is already blocked, but that is
  # desirable in case the first attempt at blocking the room failed below.
  await self.store.block_room(room_id, requester_user_id)

synapse/module_api/__init__.py

@@ -1730,6 +1730,19 @@ async def create_room(
  room_alias_str = room_alias.to_string() if room_alias else None
  return room_id, room_alias_str
 
+ async def delete_room(self, room_id: str) -> None:
+ """
+ Schedules the deletion of a room from Synapse's database.
+
+ If the room is already being deleted, this method does nothing.
+ This method does not wait for the room to be deleted.
+
+ Added in Synapse v1.89.0.
+ """
+ # Future extensions to this method might want to e.g. allow use of `force_purge`.
+ # TODO In the future we should make sure this is persistent.
+ self._hs.get_pagination_handler().start_shutdown_and_purge_room(room_id, None)
+
  async def set_displayname(
  self,
  user_id: UserID,

synapse/module_api/callbacks/third_party_event_rules_callbacks.py

@@ -40,7 +40,7 @@
  [str, StateMap[EventBase], str], Awaitable[bool]
 ]
 ON_NEW_EVENT_CALLBACK = Callable[[EventBase, StateMap[EventBase]], Awaitable]
-CHECK_CAN_SHUTDOWN_ROOM_CALLBACK = Callable[[str, str], Awaitable[bool]]
+CHECK_CAN_SHUTDOWN_ROOM_CALLBACK = Callable[[Optional[str], str], Awaitable[bool]]
 CHECK_CAN_DEACTIVATE_USER_CALLBACK = Callable[[str, bool], Awaitable[bool]]
 ON_PROFILE_UPDATE_CALLBACK = Callable[[str, ProfileInfo, bool, bool], Awaitable]
 ON_USER_DEACTIVATION_STATUS_CHANGED_CALLBACK = Callable[[str, bool, bool], Awaitable]
@@ -429,12 +429,17 @@ async def on_new_event(self, event_id: str) -> None:
  "Failed to run module API callback %s: %s", callback, e
  )
 
- async def check_can_shutdown_room(self, user_id: str, room_id: str) -> bool:
+ async def check_can_shutdown_room(
+ self, user_id: Optional[str], room_id: str
+ ) -> bool:
  """Intercept requests to shutdown a room. If `False` is returned, the
  room must not be shut down.
 
  Args:
- requester: The ID of the user requesting the shutdown.
+ user_id: The ID of the user requesting the shutdown.
+ If no user ID is supplied, then the room is being shut down through
+ some mechanism other than a user's request, e.g. through a module's
+ request.
  room_id: The ID of the room.
  """
  for callback in self._check_can_shutdown_room_callbacks: