diff options
Diffstat (limited to 'synapse/server_notices/resource_limits_server_notices.py')
| -rw-r--r-- | synapse/server_notices/resource_limits_server_notices.py | 191 |
1 files changed, 191 insertions, 0 deletions
diff --git a/synapse/server_notices/resource_limits_server_notices.py b/synapse/server_notices/resource_limits_server_notices.py new file mode 100644 index 0000000000..575697e54b --- /dev/null +++ b/synapse/server_notices/resource_limits_server_notices.py @@ -0,0 +1,191 @@ +# -*- 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 six import iteritems + +from twisted.internet import defer + +from synapse.api.constants import ( + EventTypes, + ServerNoticeLimitReached, + ServerNoticeMsgType, +) +from synapse.api.errors import AuthError, ResourceLimitError, SynapseError +from synapse.server_notices.server_notices_manager import SERVER_NOTICE_ROOM_TAG + +logger = logging.getLogger(__name__) + + +class ResourceLimitsServerNotices(object): + """ Keeps track of whether the server has reached it's resource limit and + ensures that the client is kept up to date. + """ + def __init__(self, hs): + """ + Args: + hs (synapse.server.HomeServer): + """ + self._server_notices_manager = hs.get_server_notices_manager() + self._store = hs.get_datastore() + self._auth = hs.get_auth() + self._config = hs.config + self._resouce_limited = False + self._message_handler = hs.get_message_handler() + self._state = hs.get_state_handler() + + @defer.inlineCallbacks + def maybe_send_server_notice_to_user(self, user_id): + """Check if we need to send a notice to this user, this will be true in + two cases. + 1. The server has reached its limit does not reflect this + 2. The room state indicates that the server has reached its limit when + actually the server is fine + + Args: + user_id (str): user to check + + Returns: + Deferred + """ + if self._config.hs_disabled is True: + return + + if self._config.limit_usage_by_mau is False: + return + + timestamp = yield self._store.user_last_seen_monthly_active(user_id) + if timestamp is None: + # This user will be blocked from receiving the notice anyway. + # In practice, not sure we can ever get here + return + + # Determine current state of room + + room_id = yield self._server_notices_manager.get_notice_room_for_user(user_id) + + yield self._check_and_set_tags(user_id, room_id) + currently_blocked, ref_events = yield self._is_room_currently_blocked(room_id) + + try: + # Normally should always pass in user_id if you have it, but in + # this case are checking what would happen to other users if they + # were to arrive. + try: + yield self._auth.check_auth_blocking() + is_auth_blocking = False + except ResourceLimitError as e: + is_auth_blocking = True + event_content = e.msg + event_limit_type = e.limit_type + + if currently_blocked and not is_auth_blocking: + # Room is notifying of a block, when it ought not to be. + # Remove block notification + content = { + "pinned": ref_events + } + yield self._server_notices_manager.send_notice( + user_id, content, EventTypes.Pinned, '', + ) + + elif not currently_blocked and is_auth_blocking: + # Room is not notifying of a block, when it ought to be. + # Add block notification + content = { + 'body': event_content, + 'msgtype': ServerNoticeMsgType, + 'server_notice_type': ServerNoticeLimitReached, + 'admin_uri': self._config.admin_uri, + 'limit_type': event_limit_type + } + event = yield self._server_notices_manager.send_notice( + user_id, content, EventTypes.Message, + ) + + content = { + "pinned": [ + event.event_id, + ] + } + yield self._server_notices_manager.send_notice( + user_id, content, EventTypes.Pinned, '', + ) + + except SynapseError as e: + logger.error("Error sending resource limits server notice: %s", e) + + @defer.inlineCallbacks + def _check_and_set_tags(self, user_id, room_id): + """ + Since server notices rooms were originally not with tags, + important to check that tags have been set correctly + Args: + user_id(str): the user in question + room_id(str): the server notices room for that user + """ + tags = yield self._store.get_tags_for_user(user_id) + server_notices_tags = tags.get(room_id) + need_to_set_tag = True + if server_notices_tags: + if server_notices_tags.get(SERVER_NOTICE_ROOM_TAG): + # tag already present, nothing to do here + need_to_set_tag = False + if need_to_set_tag: + yield self._store.add_tag_to_room( + user_id, room_id, SERVER_NOTICE_ROOM_TAG, None + ) + + @defer.inlineCallbacks + def _is_room_currently_blocked(self, room_id): + """ + Determines if the room is currently blocked + + Args: + room_id(str): The room id of the server notices room + + Returns: + + bool: Is the room currently blocked + list: The list of pinned events that are unrelated to limit blocking + This list can be used as a convenience in the case where the block + is to be lifted and the remaining pinned event references need to be + preserved + """ + currently_blocked = False + pinned_state_event = None + try: + pinned_state_event = yield self._state.get_current_state( + room_id, event_type=EventTypes.Pinned + ) + except AuthError: + # The user has yet to join the server notices room + pass + + referenced_events = [] + if pinned_state_event is not None: + referenced_events = pinned_state_event.content.get('pinned') + + events = yield self._store.get_events(referenced_events) + for event_id, event in iteritems(events): + if event.type != EventTypes.Message: + continue + if event.content.get("msgtype") == ServerNoticeMsgType: + currently_blocked = True + # remove event in case we need to disable blocking later on. + if event_id in referenced_events: + referenced_events.remove(event.event_id) + + defer.returnValue((currently_blocked, referenced_events)) |