#
# This file is licensed under the Affero General Public License (AGPL) version 3.
#
# Copyright (C) 2023 New Vector, Ltd
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as
# published by the Free Software Foundation, either version 3 of the
# License, or (at your option) any later version.
#
# See the GNU Affero General Public License for more details:
# <https://www.gnu.org/licenses/agpl-3.0.html>.
#
# Originally licensed under the Apache License, Version 2.0:
# <http://www.apache.org/licenses/LICENSE-2.0>.
#
# [This file includes modifications made by New Vector Limited]
#
#
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 JsonDict, 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._storage_controllers = hs.get_storage_controllers()
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,
)
await self._update_room_info(
requester,
room_id,
EventTypes.Name,
"name",
self._config.servernotices.server_notices_room_name,
)
await self._update_room_info(
requester,
room_id,
EventTypes.RoomAvatar,
"url",
self._config.servernotices.server_notices_room_avatar_url,
)
await self._update_room_info(
requester,
room_id,
EventTypes.Topic,
"topic",
self._config.servernotices.server_notices_room_topic,
)
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,
}
room_config: JsonDict = {
"preset": RoomCreationPreset.PRIVATE_CHAT,
"power_level_content_override": {"users_default": -10},
}
if self._config.servernotices.server_notices_room_name:
room_config["name"] = self._config.servernotices.server_notices_room_name
if self._config.servernotices.server_notices_room_topic:
room_config["topic"] = self._config.servernotices.server_notices_room_topic
if self._config.servernotices.server_notices_room_avatar_url:
room_config["initial_state"] = [
{
"type": EventTypes.RoomAvatar,
"state_key": "",
"content": {
"url": self._config.servernotices.server_notices_room_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=room_config,
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
user_id_obj = UserID.from_string(user_id)
await self._room_member_handler.update_membership(
requester=requester,
target=user_id_obj,
room_id=room_id,
action="invite",
ratelimit=False,
)
if self._config.servernotices.server_notices_auto_join:
user_requester = create_requester(
user_id, authenticated_entity=self._server_name
)
await self._room_member_handler.update_membership(
requester=user_requester,
target=user_id_obj,
room_id=room_id,
action="join",
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._storage_controllers.state.get_current_state_event(
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},
)
async def _update_room_info(
self,
requester: Requester,
room_id: str,
info_event_type: str,
info_content_key: str,
info_value: Optional[str],
) -> None:
"""
Updates a specific notice room's info if it's different from what is set.
Args:
requester: The user who is performing the update.
room_id: The ID of the server notice room
info_event_type: The event type holding the specific info
info_content_key: The key containing the specific info in the event's content
info_value: The expected value for the specific info
"""
room_info_event = await self._storage_controllers.state.get_current_state_event(
room_id,
info_event_type,
"",
)
existing_info_value = None
if room_info_event:
existing_info_value = room_info_event.get(info_content_key)
if existing_info_value == info_value:
return
if not existing_info_value and not info_value:
# A missing `info_value` can either be represented by a None
# or an empty string, so we assume that if they're both falsey
# they're equivalent.
return
if info_value is None:
info_value = ""
room_info_event_dict = {
"type": info_event_type,
"room_id": room_id,
"sender": requester.user.to_string(),
"state_key": "",
"content": {
info_content_key: info_value,
},
}
event, _ = await self._event_creation_handler.create_and_send_nonmember_event(
requester, room_info_event_dict, ratelimit=False
)