mirror of
https://mau.dev/maunium/synapse.git
synced 2024-08-26 12:16:12 +00:00
![Richard van der Hoff](/assets/img/avatar_default.png)
Currently, we try to pull the event corresponding to a sync token from the database. However, when we fetch redaction events, we check the target of that redaction (because we aren't allowed to send redactions to clients without validating them). So, if the sync token points to a redaction of an event that we don't have, we have a problem. It turns out we don't really need that event, and can just work with its ID and metadata, which sidesteps the whole problem.
680 lines
24 KiB
Python
680 lines
24 KiB
Python
# Copyright 2014-2016 OpenMarket Ltd
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# Copyright 2020 The Matrix.org Foundation C.I.C.
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#
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# Licensed under the Apache License, Version 2.0 (the "License");
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# you may not use this file except in compliance with the License.
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# You may obtain a copy of the License at
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#
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# http://www.apache.org/licenses/LICENSE-2.0
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#
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# Unless required by applicable law or agreed to in writing, software
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# distributed under the License is distributed on an "AS IS" BASIS,
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# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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# See the License for the specific language governing permissions and
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# limitations under the License.
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import collections.abc
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import logging
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from typing import TYPE_CHECKING, Collection, Dict, Iterable, Optional, Set, Tuple
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import attr
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from synapse.api.constants import EventTypes, Membership
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from synapse.api.errors import NotFoundError, UnsupportedRoomVersionError
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from synapse.api.room_versions import KNOWN_ROOM_VERSIONS, RoomVersion
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from synapse.events import EventBase
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from synapse.events.snapshot import EventContext
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from synapse.storage._base import SQLBaseStore
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from synapse.storage.database import (
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DatabasePool,
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LoggingDatabaseConnection,
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LoggingTransaction,
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make_in_list_sql_clause,
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)
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from synapse.storage.databases.main.events_worker import EventsWorkerStore
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from synapse.storage.databases.main.roommember import RoomMemberWorkerStore
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from synapse.storage.state import StateFilter
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from synapse.types import JsonDict, JsonMapping, StateMap
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from synapse.util.caches import intern_string
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from synapse.util.caches.descriptors import cached, cachedList
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from synapse.util.iterutils import batch_iter
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if TYPE_CHECKING:
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from synapse.server import HomeServer
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logger = logging.getLogger(__name__)
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MAX_STATE_DELTA_HOPS = 100
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@attr.s(slots=True, frozen=True, auto_attribs=True)
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class EventMetadata:
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"""Returned by `get_metadata_for_events`"""
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room_id: str
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event_type: str
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state_key: Optional[str]
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rejection_reason: Optional[str]
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def _retrieve_and_check_room_version(room_id: str, room_version_id: str) -> RoomVersion:
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v = KNOWN_ROOM_VERSIONS.get(room_version_id)
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if not v:
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raise UnsupportedRoomVersionError(
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"Room %s uses a room version %s which is no longer supported"
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% (room_id, room_version_id)
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)
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return v
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# this inherits from EventsWorkerStore because it calls self.get_events
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class StateGroupWorkerStore(EventsWorkerStore, SQLBaseStore):
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"""The parts of StateGroupStore that can be called from workers."""
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def __init__(
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self,
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database: DatabasePool,
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db_conn: LoggingDatabaseConnection,
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hs: "HomeServer",
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):
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super().__init__(database, db_conn, hs)
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async def get_room_version(self, room_id: str) -> RoomVersion:
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"""Get the room_version of a given room
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Raises:
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NotFoundError: if the room is unknown
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UnsupportedRoomVersionError: if the room uses an unknown room version.
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Typically this happens if support for the room's version has been
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removed from Synapse.
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"""
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room_version_id = await self.get_room_version_id(room_id)
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return _retrieve_and_check_room_version(room_id, room_version_id)
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def get_room_version_txn(
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self, txn: LoggingTransaction, room_id: str
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) -> RoomVersion:
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"""Get the room_version of a given room
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Args:
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txn: Transaction object
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room_id: The room_id of the room you are trying to get the version for
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Raises:
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NotFoundError: if the room is unknown
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UnsupportedRoomVersionError: if the room uses an unknown room version.
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Typically this happens if support for the room's version has been
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removed from Synapse.
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"""
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room_version_id = self.get_room_version_id_txn(txn, room_id)
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return _retrieve_and_check_room_version(room_id, room_version_id)
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@cached(max_entries=10000)
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async def get_room_version_id(self, room_id: str) -> str:
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"""Get the room_version of a given room
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Raises:
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NotFoundError: if the room is unknown
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"""
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return await self.db_pool.runInteraction(
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"get_room_version_id_txn",
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self.get_room_version_id_txn,
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room_id,
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)
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def get_room_version_id_txn(self, txn: LoggingTransaction, room_id: str) -> str:
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"""Get the room_version of a given room
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Args:
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txn: Transaction object
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room_id: The room_id of the room you are trying to get the version for
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Raises:
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NotFoundError: if the room is unknown
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"""
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# First we try looking up room version from the database, but for old
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# rooms we might not have added the room version to it yet so we fall
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# back to previous behaviour and look in current state events.
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#
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# We really should have an entry in the rooms table for every room we
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# care about, but let's be a bit paranoid (at least while the background
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# update is happening) to avoid breaking existing rooms.
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room_version = self.db_pool.simple_select_one_onecol_txn(
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txn,
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table="rooms",
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keyvalues={"room_id": room_id},
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retcol="room_version",
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allow_none=True,
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)
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if room_version is None:
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raise NotFoundError("Could not find room_version for %s" % (room_id,))
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return room_version
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async def get_metadata_for_events(
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self, event_ids: Collection[str]
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) -> Dict[str, EventMetadata]:
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"""Get some metadata (room_id, type, state_key) for the given events.
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This method is a faster alternative than fetching the full events from
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the DB, and should be used when the full event is not needed.
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Returns metadata for rejected and redacted events. Events that have not
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been persisted are omitted from the returned dict.
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"""
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def get_metadata_for_events_txn(
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txn: LoggingTransaction,
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batch_ids: Collection[str],
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) -> Dict[str, EventMetadata]:
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clause, args = make_in_list_sql_clause(
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self.database_engine, "e.event_id", batch_ids
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)
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sql = f"""
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SELECT e.event_id, e.room_id, e.type, se.state_key, r.reason
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FROM events AS e
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LEFT JOIN state_events se USING (event_id)
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LEFT JOIN rejections r USING (event_id)
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WHERE {clause}
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"""
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txn.execute(sql, args)
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return {
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event_id: EventMetadata(
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room_id=room_id,
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event_type=event_type,
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state_key=state_key,
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rejection_reason=rejection_reason,
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)
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for event_id, room_id, event_type, state_key, rejection_reason in txn
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}
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result_map: Dict[str, EventMetadata] = {}
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for batch_ids in batch_iter(event_ids, 1000):
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result_map.update(
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await self.db_pool.runInteraction(
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"get_metadata_for_events",
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get_metadata_for_events_txn,
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batch_ids=batch_ids,
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)
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)
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return result_map
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async def get_room_predecessor(self, room_id: str) -> Optional[JsonMapping]:
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"""Get the predecessor of an upgraded room if it exists.
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Otherwise return None.
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Args:
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room_id: The room ID.
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Returns:
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A dictionary containing the structure of the predecessor
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field from the room's create event. The structure is subject to other servers,
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but it is expected to be:
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* room_id (str): The room ID of the predecessor room
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* event_id (str): The ID of the tombstone event in the predecessor room
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None if a predecessor key is not found, or is not a dictionary.
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Raises:
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NotFoundError if the given room is unknown
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"""
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# Retrieve the room's create event
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create_event = await self.get_create_event_for_room(room_id)
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# Retrieve the predecessor key of the create event
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predecessor = create_event.content.get("predecessor", None)
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# Ensure the key is a dictionary
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if not isinstance(predecessor, collections.abc.Mapping):
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return None
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# The keys must be strings since the data is JSON.
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return predecessor
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async def get_create_event_for_room(self, room_id: str) -> EventBase:
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"""Get the create state event for a room.
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Args:
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room_id: The room ID.
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Returns:
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The room creation event.
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Raises:
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NotFoundError if the room is unknown
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"""
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state_ids = await self.get_current_state_ids(room_id)
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if not state_ids:
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raise NotFoundError(f"Current state for room {room_id} is empty")
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create_id = state_ids.get((EventTypes.Create, ""))
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# If we can't find the create event, assume we've hit a dead end
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if not create_id:
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raise NotFoundError(f"No create event in current state for room {room_id}")
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# Retrieve the room's create event and return
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create_event = await self.get_event(create_id)
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return create_event
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@cached(max_entries=100000, iterable=True)
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async def get_current_state_ids(self, room_id: str) -> StateMap[str]:
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"""Get the current state event ids for a room based on the
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current_state_events table.
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Args:
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room_id: The room to get the state IDs of.
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Returns:
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The current state of the room.
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"""
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def _get_current_state_ids_txn(txn: LoggingTransaction) -> StateMap[str]:
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txn.execute(
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"""SELECT type, state_key, event_id FROM current_state_events
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WHERE room_id = ?
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""",
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(room_id,),
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)
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return {(intern_string(r[0]), intern_string(r[1])): r[2] for r in txn}
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return await self.db_pool.runInteraction(
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"get_current_state_ids", _get_current_state_ids_txn
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)
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# FIXME: how should this be cached?
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async def get_filtered_current_state_ids(
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self, room_id: str, state_filter: Optional[StateFilter] = None
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) -> StateMap[str]:
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"""Get the current state event of a given type for a room based on the
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current_state_events table. This may not be as up-to-date as the result
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of doing a fresh state resolution as per state_handler.get_current_state
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Args:
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room_id
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state_filter: The state filter used to fetch state
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from the database.
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Returns:
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Map from type/state_key to event ID.
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"""
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where_clause, where_args = (
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state_filter or StateFilter.all()
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).make_sql_filter_clause()
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if not where_clause:
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# We delegate to the cached version
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return await self.get_current_state_ids(room_id)
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def _get_filtered_current_state_ids_txn(
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txn: LoggingTransaction,
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) -> StateMap[str]:
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results = {}
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sql = """
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SELECT type, state_key, event_id FROM current_state_events
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WHERE room_id = ?
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"""
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if where_clause:
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sql += " AND (%s)" % (where_clause,)
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args = [room_id]
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args.extend(where_args)
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txn.execute(sql, args)
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for row in txn:
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typ, state_key, event_id = row
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key = (intern_string(typ), intern_string(state_key))
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results[key] = event_id
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return results
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return await self.db_pool.runInteraction(
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"get_filtered_current_state_ids", _get_filtered_current_state_ids_txn
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)
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async def get_canonical_alias_for_room(self, room_id: str) -> Optional[str]:
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"""Get canonical alias for room, if any
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Args:
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room_id: The room ID
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Returns:
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The canonical alias, if any
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"""
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state = await self.get_filtered_current_state_ids(
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room_id, StateFilter.from_types([(EventTypes.CanonicalAlias, "")])
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)
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event_id = state.get((EventTypes.CanonicalAlias, ""))
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if not event_id:
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return None
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event = await self.get_event(event_id, allow_none=True)
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if not event:
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return None
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return event.content.get("canonical_alias")
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@cached(max_entries=50000)
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async def _get_state_group_for_event(self, event_id: str) -> Optional[int]:
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return await self.db_pool.simple_select_one_onecol(
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table="event_to_state_groups",
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keyvalues={"event_id": event_id},
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retcol="state_group",
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allow_none=True,
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desc="_get_state_group_for_event",
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)
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@cachedList(
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cached_method_name="_get_state_group_for_event",
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list_name="event_ids",
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num_args=1,
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)
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async def _get_state_group_for_events(
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self, event_ids: Collection[str]
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) -> Dict[str, int]:
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"""Returns mapping event_id -> state_group.
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Raises:
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RuntimeError if the state is unknown at any of the given events
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"""
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rows = await self.db_pool.simple_select_many_batch(
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table="event_to_state_groups",
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column="event_id",
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iterable=event_ids,
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keyvalues={},
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retcols=("event_id", "state_group"),
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desc="_get_state_group_for_events",
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)
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res = {row["event_id"]: row["state_group"] for row in rows}
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for e in event_ids:
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if e not in res:
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raise RuntimeError("No state group for unknown or outlier event %s" % e)
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return res
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async def get_referenced_state_groups(
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self, state_groups: Iterable[int]
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) -> Set[int]:
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"""Check if the state groups are referenced by events.
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Args:
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state_groups
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Returns:
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The subset of state groups that are referenced.
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"""
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rows = await self.db_pool.simple_select_many_batch(
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table="event_to_state_groups",
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column="state_group",
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iterable=state_groups,
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keyvalues={},
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retcols=("DISTINCT state_group",),
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desc="get_referenced_state_groups",
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)
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return {row["state_group"] for row in rows}
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async def update_state_for_partial_state_event(
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self,
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event: EventBase,
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context: EventContext,
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) -> None:
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"""Update the state group for a partial state event"""
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await self.db_pool.runInteraction(
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"update_state_for_partial_state_event",
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self._update_state_for_partial_state_event_txn,
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event,
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context,
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)
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def _update_state_for_partial_state_event_txn(
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self,
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txn: LoggingTransaction,
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event: EventBase,
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context: EventContext,
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) -> None:
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# we shouldn't have any outliers here
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assert not event.internal_metadata.is_outlier()
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# anything that was rejected should have the same state as its
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# predecessor.
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if context.rejected:
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assert context.state_group == context.state_group_before_event
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self.db_pool.simple_update_txn(
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txn,
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table="event_to_state_groups",
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keyvalues={"event_id": event.event_id},
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updatevalues={"state_group": context.state_group},
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)
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self.db_pool.simple_delete_one_txn(
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txn,
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table="partial_state_events",
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keyvalues={"event_id": event.event_id},
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)
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# TODO(faster_joins): need to do something about workers here
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txn.call_after(self.is_partial_state_event.invalidate, (event.event_id,))
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txn.call_after(
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self._get_state_group_for_event.prefill,
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(event.event_id,),
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context.state_group,
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)
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class MainStateBackgroundUpdateStore(RoomMemberWorkerStore):
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CURRENT_STATE_INDEX_UPDATE_NAME = "current_state_members_idx"
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EVENT_STATE_GROUP_INDEX_UPDATE_NAME = "event_to_state_groups_sg_index"
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DELETE_CURRENT_STATE_UPDATE_NAME = "delete_old_current_state_events"
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def __init__(
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self,
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database: DatabasePool,
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db_conn: LoggingDatabaseConnection,
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hs: "HomeServer",
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):
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super().__init__(database, db_conn, hs)
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self.server_name: str = hs.hostname
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self.db_pool.updates.register_background_index_update(
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self.CURRENT_STATE_INDEX_UPDATE_NAME,
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index_name="current_state_events_member_index",
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table="current_state_events",
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columns=["state_key"],
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where_clause="type='m.room.member'",
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)
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self.db_pool.updates.register_background_index_update(
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self.EVENT_STATE_GROUP_INDEX_UPDATE_NAME,
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index_name="event_to_state_groups_sg_index",
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table="event_to_state_groups",
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columns=["state_group"],
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)
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self.db_pool.updates.register_background_update_handler(
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self.DELETE_CURRENT_STATE_UPDATE_NAME,
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self._background_remove_left_rooms,
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)
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async def _background_remove_left_rooms(
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self, progress: JsonDict, batch_size: int
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) -> int:
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"""Background update to delete rows from `current_state_events` and
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`event_forward_extremities` tables of rooms that the server is no
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longer joined to.
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"""
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last_room_id = progress.get("last_room_id", "")
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|
def _background_remove_left_rooms_txn(
|
|
txn: LoggingTransaction,
|
|
) -> Tuple[bool, Set[str]]:
|
|
# get a batch of room ids to consider
|
|
sql = """
|
|
SELECT DISTINCT room_id FROM current_state_events
|
|
WHERE room_id > ? ORDER BY room_id LIMIT ?
|
|
"""
|
|
|
|
txn.execute(sql, (last_room_id, batch_size))
|
|
room_ids = [row[0] for row in txn]
|
|
if not room_ids:
|
|
return True, set()
|
|
|
|
###########################################################################
|
|
#
|
|
# exclude rooms where we have active members
|
|
|
|
sql = """
|
|
SELECT room_id
|
|
FROM local_current_membership
|
|
WHERE
|
|
room_id > ? AND room_id <= ?
|
|
AND membership = 'join'
|
|
GROUP BY room_id
|
|
"""
|
|
|
|
txn.execute(sql, (last_room_id, room_ids[-1]))
|
|
joined_room_ids = {row[0] for row in txn}
|
|
to_delete = set(room_ids) - joined_room_ids
|
|
|
|
###########################################################################
|
|
#
|
|
# exclude rooms which we are in the process of constructing; these otherwise
|
|
# qualify as "rooms with no local users", and would have their
|
|
# forward extremities cleaned up.
|
|
|
|
# the following query will return a list of rooms which have forward
|
|
# extremities that are *not* also the create event in the room - ie
|
|
# those that are not being created currently.
|
|
|
|
sql = """
|
|
SELECT DISTINCT efe.room_id
|
|
FROM event_forward_extremities efe
|
|
LEFT JOIN current_state_events cse ON
|
|
cse.event_id = efe.event_id
|
|
AND cse.type = 'm.room.create'
|
|
AND cse.state_key = ''
|
|
WHERE
|
|
cse.event_id IS NULL
|
|
AND efe.room_id > ? AND efe.room_id <= ?
|
|
"""
|
|
|
|
txn.execute(sql, (last_room_id, room_ids[-1]))
|
|
|
|
# build a set of those rooms within `to_delete` that do not appear in
|
|
# the above, leaving us with the rooms in `to_delete` that *are* being
|
|
# created.
|
|
creating_rooms = to_delete.difference(row[0] for row in txn)
|
|
logger.info("skipping rooms which are being created: %s", creating_rooms)
|
|
|
|
# now remove the rooms being created from the list of those to delete.
|
|
#
|
|
# (we could have just taken the intersection of `to_delete` with the result
|
|
# of the sql query, but it's useful to be able to log `creating_rooms`; and
|
|
# having done so, it's quicker to remove the (few) creating rooms from
|
|
# `to_delete` than it is to form the intersection with the (larger) list of
|
|
# not-creating-rooms)
|
|
|
|
to_delete -= creating_rooms
|
|
|
|
###########################################################################
|
|
#
|
|
# now clear the state for the rooms
|
|
|
|
logger.info("Deleting current state left rooms: %r", to_delete)
|
|
|
|
# First we get all users that we still think were joined to the
|
|
# room. This is so that we can mark those device lists as
|
|
# potentially stale, since there may have been a period where the
|
|
# server didn't share a room with the remote user and therefore may
|
|
# have missed any device updates.
|
|
rows = self.db_pool.simple_select_many_txn(
|
|
txn,
|
|
table="current_state_events",
|
|
column="room_id",
|
|
iterable=to_delete,
|
|
keyvalues={"type": EventTypes.Member, "membership": Membership.JOIN},
|
|
retcols=("state_key",),
|
|
)
|
|
|
|
potentially_left_users = {row["state_key"] for row in rows}
|
|
|
|
# Now lets actually delete the rooms from the DB.
|
|
self.db_pool.simple_delete_many_txn(
|
|
txn,
|
|
table="current_state_events",
|
|
column="room_id",
|
|
values=to_delete,
|
|
keyvalues={},
|
|
)
|
|
|
|
self.db_pool.simple_delete_many_txn(
|
|
txn,
|
|
table="event_forward_extremities",
|
|
column="room_id",
|
|
values=to_delete,
|
|
keyvalues={},
|
|
)
|
|
|
|
self.db_pool.updates._background_update_progress_txn(
|
|
txn,
|
|
self.DELETE_CURRENT_STATE_UPDATE_NAME,
|
|
{"last_room_id": room_ids[-1]},
|
|
)
|
|
|
|
return False, potentially_left_users
|
|
|
|
finished, potentially_left_users = await self.db_pool.runInteraction(
|
|
"_background_remove_left_rooms", _background_remove_left_rooms_txn
|
|
)
|
|
|
|
if finished:
|
|
await self.db_pool.updates._end_background_update(
|
|
self.DELETE_CURRENT_STATE_UPDATE_NAME
|
|
)
|
|
|
|
# Now go and check if we still share a room with the remote users in
|
|
# the deleted rooms. If not mark their device lists as stale.
|
|
joined_users = await self.get_users_server_still_shares_room_with(
|
|
potentially_left_users
|
|
)
|
|
|
|
for user_id in potentially_left_users - joined_users:
|
|
await self.mark_remote_user_device_list_as_unsubscribed(user_id) # type: ignore[attr-defined]
|
|
|
|
return batch_size
|
|
|
|
|
|
class StateStore(StateGroupWorkerStore, MainStateBackgroundUpdateStore):
|
|
"""Keeps track of the state at a given event.
|
|
|
|
This is done by the concept of `state groups`. Every event is a assigned
|
|
a state group (identified by an arbitrary string), which references a
|
|
collection of state events. The current state of an event is then the
|
|
collection of state events referenced by the event's state group.
|
|
|
|
Hence, every change in the current state causes a new state group to be
|
|
generated. However, if no change happens (e.g., if we get a message event
|
|
with only one parent it inherits the state group from its parent.)
|
|
|
|
There are three tables:
|
|
* `state_groups`: Stores group name, first event with in the group and
|
|
room id.
|
|
* `event_to_state_groups`: Maps events to state groups.
|
|
* `state_groups_state`: Maps state group to state events.
|
|
"""
|
|
|
|
def __init__(
|
|
self,
|
|
database: DatabasePool,
|
|
db_conn: LoggingDatabaseConnection,
|
|
hs: "HomeServer",
|
|
):
|
|
super().__init__(database, db_conn, hs)
|