diff --git a/synapse/server_notices/server_notices_manager.py b/synapse/server_notices/server_notices_manager.py
new file mode 100644
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+++ b/synapse/server_notices/server_notices_manager.py
@@ -0,0 +1,131 @@
+# -*- coding: utf-8 -*-
+# 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 twisted.internet import defer
+
+from synapse.api.constants import EventTypes, Membership, RoomCreationPreset
+from synapse.types import create_requester
+from synapse.util.caches.descriptors import cachedInlineCallbacks
+
+logger = logging.getLogger(__name__)
+
+
+class ServerNoticesManager(object):
+ def __init__(self, hs):
+ """
+
+ Args:
+ hs (synapse.server.HomeServer):
+ """
+
+ self._store = hs.get_datastore()
+ self._config = hs.config
+ self._room_creation_handler = hs.get_room_creation_handler()
+ self._event_creation_handler = hs.get_event_creation_handler()
+
+ def is_enabled(self):
+ """Checks if server notices are enabled on this server.
+
+ Returns:
+ bool
+ """
+ return self._config.server_notices_mxid is not None
+
+ @defer.inlineCallbacks
+ def send_notice(self, user_id, event_content):
+ """Send a notice to the given user
+
+ Creates the server notices room, if none exists.
+
+ Args:
+ user_id (str): mxid of user to send event to.
+ event_content (dict): content of event to send
+
+ Returns:
+ Deferrred[None]
+ """
+ room_id = yield self.get_notice_room_for_user(user_id)
+
+ system_mxid = self._config.server_notices_mxid
+ requester = create_requester(system_mxid)
+
+ logger.info("Sending server notice to %s", user_id)
+
+ yield self._event_creation_handler.create_and_send_nonmember_event(
+ requester, {
+ "type": EventTypes.Message,
+ "room_id": room_id,
+ "sender": system_mxid,
+ "content": event_content,
+ },
+ ratelimit=False,
+ )
+
+ @cachedInlineCallbacks()
+ def get_notice_room_for_user(self, user_id):
+ """Get the room for notices for a given user
+
+ If we have not yet created a notice room for this user, create it
+
+ Args:
+ user_id (str): complete user id for the user we want a room for
+
+ Returns:
+ str: room id of notice room.
+ """
+ if not self.is_enabled():
+ raise Exception("Server notices not enabled")
+
+ rooms = yield self._store.get_rooms_for_user_where_membership_is(
+ user_id, [Membership.INVITE, Membership.JOIN],
+ )
+ system_mxid = self._config.server_notices_mxid
+ 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.
+ user_ids = yield self._store.get_users_in_room(room.room_id)
+ if system_mxid in user_ids:
+ # we found a room which our user shares with the system notice
+ # user
+ logger.info("Using room %s", room.room_id)
+ defer.returnValue(room.room_id)
+
+ # apparently no existing notice room: create a new one
+ logger.info("Creating server notices room for %s", user_id)
+
+ requester = create_requester(system_mxid)
+ info = yield self._room_creation_handler.create_room(
+ requester,
+ config={
+ "preset": RoomCreationPreset.PRIVATE_CHAT,
+ "name": self._config.server_notices_room_name,
+ "power_level_content_override": {
+ "users_default": -10,
+ },
+ "invite": (user_id,)
+ },
+ ratelimit=False,
+ creator_join_profile={
+ "displayname": self._config.server_notices_mxid_display_name,
+ },
+ )
+ room_id = info['room_id']
+
+ logger.info("Created server notices room %s for %s", room_id, user_id)
+ defer.returnValue(room_id)
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