# Copyright 2018 New Vector Ltd # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. import logging from typing import TYPE_CHECKING, Optional from synapse.api.constants import EventTypes, Membership, RoomCreationPreset from synapse.events import EventBase from synapse.types import Requester, StreamKeyType, UserID, create_requester from synapse.util.caches.descriptors import cached if TYPE_CHECKING: from synapse.server import HomeServer logger = logging.getLogger(__name__) SERVER_NOTICE_ROOM_TAG = "m.server_notice" class ServerNoticesManager: def __init__(self, hs: "HomeServer"): self._store = hs.get_datastores().main self._config = hs.config self._account_data_handler = hs.get_account_data_handler() self._room_creation_handler = hs.get_room_creation_handler() self._room_member_handler = hs.get_room_member_handler() self._event_creation_handler = hs.get_event_creation_handler() self._message_handler = hs.get_message_handler() self._is_mine_id = hs.is_mine_id self._server_name = hs.hostname self._notifier = hs.get_notifier() self.server_notices_mxid = self._config.servernotices.server_notices_mxid def is_enabled(self) -> bool: """Checks if server notices are enabled on this server.""" return self.server_notices_mxid is not None async def send_notice( self, user_id: str, event_content: dict, type: str = EventTypes.Message, state_key: Optional[str] = None, txn_id: Optional[str] = None, ) -> EventBase: """Send a notice to the given user Creates the server notices room, if none exists. Args: user_id: mxid of user to send event to. event_content: content of event to send type: type of event is_state_event: Is the event a state event txn_id: The transaction ID. """ room_id = await self.get_or_create_notice_room_for_user(user_id) await self.maybe_invite_user_to_room(user_id, room_id) assert self.server_notices_mxid is not None requester = create_requester( self.server_notices_mxid, authenticated_entity=self._server_name ) logger.info("Sending server notice to %s", user_id) event_dict = { "type": type, "room_id": room_id, "sender": self.server_notices_mxid, "content": event_content, } if state_key is not None: event_dict["state_key"] = state_key event, _ = await self._event_creation_handler.create_and_send_nonmember_event( requester, event_dict, ratelimit=False, txn_id=txn_id ) return event @cached() async def maybe_get_notice_room_for_user(self, user_id: str) -> Optional[str]: """Try to look up the server notice room for this user if it exists. Does not create one if none can be found. Args: user_id: the user we want a server notice room for. Returns: The room's ID, or None if no room could be found. """ # If there is no server notices MXID, then there is no server notices room if self.server_notices_mxid is None: return None rooms = await self._store.get_rooms_for_local_user_where_membership_is( user_id, [Membership.INVITE, Membership.JOIN] ) for room in rooms: # it's worth noting that there is an asymmetry here in that we # expect the user to be invited or joined, but the system user must # be joined. This is kinda deliberate, in that if somebody somehow # manages to invite the system user to a room, that doesn't make it # the server notices room. is_server_notices_room = await self._store.check_local_user_in_room( user_id=self.server_notices_mxid, room_id=room.room_id ) if is_server_notices_room: # we found a room which our user shares with the system notice # user return room.room_id return None @cached() async def get_or_create_notice_room_for_user(self, user_id: str) -> str: """Get the room for notices for a given user If we have not yet created a notice room for this user, create it, but don't invite the user to it. Args: user_id: complete user id for the user we want a room for Returns: room id of notice room. """ if self.server_notices_mxid is None: raise Exception("Server notices not enabled") assert self._is_mine_id(user_id), "Cannot send server notices to remote users" requester = create_requester( self.server_notices_mxid, authenticated_entity=self._server_name ) room_id = await self.maybe_get_notice_room_for_user(user_id) if room_id is not None: logger.info( "Using existing server notices room %s for user %s", room_id, user_id, ) await self._update_notice_user_profile_if_changed( requester, room_id, self._config.servernotices.server_notices_mxid_display_name, self._config.servernotices.server_notices_mxid_avatar_url, ) return room_id # apparently no existing notice room: create a new one logger.info("Creating server notices room for %s", user_id) # see if we want to override the profile info for the server user. # note that if we want to override either the display name or the # avatar, we have to use both. join_profile = None if ( self._config.servernotices.server_notices_mxid_display_name is not None or self._config.servernotices.server_notices_mxid_avatar_url is not None ): join_profile = { "displayname": self._config.servernotices.server_notices_mxid_display_name, "avatar_url": self._config.servernotices.server_notices_mxid_avatar_url, } # `ignore_forced_encryption` is used to bypass `encryption_enabled_by_default_for_room_type` # setting if it set, since the server notices will not be encrypted anyway. room_id, _, _ = await self._room_creation_handler.create_room( requester, config={ "preset": RoomCreationPreset.PRIVATE_CHAT, "name": self._config.servernotices.server_notices_room_name, "power_level_content_override": {"users_default": -10}, }, ratelimit=False, creator_join_profile=join_profile, ignore_forced_encryption=True, ) self.maybe_get_notice_room_for_user.invalidate((user_id,)) max_id = await self._account_data_handler.add_tag_to_room( user_id, room_id, SERVER_NOTICE_ROOM_TAG, {} ) self._notifier.on_new_event(StreamKeyType.ACCOUNT_DATA, max_id, users=[user_id]) logger.info("Created server notices room %s for %s", room_id, user_id) return room_id async def maybe_invite_user_to_room(self, user_id: str, room_id: str) -> None: """Invite the given user to the given server room, unless the user has already joined or been invited to it. Args: user_id: The ID of the user to invite. room_id: The ID of the room to invite the user to. """ assert self.server_notices_mxid is not None requester = create_requester( self.server_notices_mxid, authenticated_entity=self._server_name ) # Check whether the user has already joined or been invited to this room. If # that's the case, there is no need to re-invite them. joined_rooms = await self._store.get_rooms_for_local_user_where_membership_is( user_id, [Membership.INVITE, Membership.JOIN] ) for room in joined_rooms: if room.room_id == room_id: return await self._room_member_handler.update_membership( requester=requester, target=UserID.from_string(user_id), room_id=room_id, action="invite", ratelimit=False, ) async def _update_notice_user_profile_if_changed( self, requester: Requester, room_id: str, display_name: Optional[str], avatar_url: Optional[str], ) -> None: """ Updates the notice user's profile if it's different from what is in the room. Args: requester: The user who is performing the update. room_id: The ID of the server notice room display_name: The displayname of the server notice user avatar_url: The avatar url of the server notice user """ logger.debug("Checking whether notice user profile has changed for %s", room_id) assert self.server_notices_mxid is not None notice_user_data_in_room = await self._message_handler.get_room_data( create_requester(self.server_notices_mxid), room_id, EventTypes.Member, self.server_notices_mxid, ) assert notice_user_data_in_room is not None notice_user_profile_changed = ( display_name != notice_user_data_in_room.content.get("displayname") or avatar_url != notice_user_data_in_room.content.get("avatar_url") ) if notice_user_profile_changed: logger.info("Updating notice user profile in room %s", room_id) await self._room_member_handler.update_membership( requester=requester, target=UserID.from_string(self.server_notices_mxid), room_id=room_id, action="join", ratelimit=False, content={"displayname": display_name, "avatar_url": avatar_url}, )