77 lines
2.5 KiB
Python
77 lines
2.5 KiB
Python
# -*- 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 typing import TYPE_CHECKING, Optional
|
|
|
|
if TYPE_CHECKING:
|
|
from synapse.app.homeserver import HomeServer
|
|
|
|
logger = logging.getLogger(__name__)
|
|
|
|
|
|
class StateDeltasHandler:
|
|
def __init__(self, hs: "HomeServer"):
|
|
self.store = hs.get_datastore()
|
|
|
|
async def _get_key_change(
|
|
self,
|
|
prev_event_id: Optional[str],
|
|
event_id: Optional[str],
|
|
key_name: str,
|
|
public_value: str,
|
|
) -> Optional[bool]:
|
|
"""Given two events check if the `key_name` field in content changed
|
|
from not matching `public_value` to doing so.
|
|
|
|
For example, check if `history_visibility` (`key_name`) changed from
|
|
`shared` to `world_readable` (`public_value`).
|
|
|
|
Returns:
|
|
None if the field in the events either both match `public_value`
|
|
or if neither do, i.e. there has been no change.
|
|
True if it didn't match `public_value` but now does
|
|
False if it did match `public_value` but now doesn't
|
|
"""
|
|
prev_event = None
|
|
event = None
|
|
if prev_event_id:
|
|
prev_event = await self.store.get_event(prev_event_id, allow_none=True)
|
|
|
|
if event_id:
|
|
event = await self.store.get_event(event_id, allow_none=True)
|
|
|
|
if not event and not prev_event:
|
|
logger.debug("Neither event exists: %r %r", prev_event_id, event_id)
|
|
return None
|
|
|
|
prev_value = None
|
|
value = None
|
|
|
|
if prev_event:
|
|
prev_value = prev_event.content.get(key_name)
|
|
|
|
if event:
|
|
value = event.content.get(key_name)
|
|
|
|
logger.debug("prev_value: %r -> value: %r", prev_value, value)
|
|
|
|
if value == public_value and prev_value != public_value:
|
|
return True
|
|
elif value != public_value and prev_value == public_value:
|
|
return False
|
|
else:
|
|
return None
|