756 lines
		
	
	
		
			29 KiB
		
	
	
	
		
			Python
		
	
	
			
		
		
	
	
			756 lines
		
	
	
		
			29 KiB
		
	
	
	
		
			Python
		
	
	
# Copyright 2014 - 2016 OpenMarket Ltd
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# Copyright 2017 - 2018 New Vector Ltd
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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 logging
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from typing import TYPE_CHECKING, List, Optional, Set, Tuple, cast
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from twisted.python.failure import Failure
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from synapse.api.constants import Direction, EventTypes, Membership
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from synapse.api.errors import SynapseError
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from synapse.api.filtering import Filter
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from synapse.events.utils import SerializeEventConfig
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from synapse.handlers.room import ShutdownRoomParams, ShutdownRoomResponse
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from synapse.handlers.worker_lock import NEW_EVENT_DURING_PURGE_LOCK_NAME
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from synapse.logging.opentracing import trace
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from synapse.metrics.background_process_metrics import run_as_background_process
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from synapse.rest.admin._base import assert_user_is_admin
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from synapse.streams.config import PaginationConfig
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from synapse.types import (
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    JsonDict,
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    JsonMapping,
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    Requester,
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    ScheduledTask,
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    StreamKeyType,
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    TaskStatus,
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)
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from synapse.types.state import StateFilter
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from synapse.util.async_helpers import ReadWriteLock
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from synapse.visibility import filter_events_for_client
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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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# How many single event gaps we tolerate returning in a `/messages` response before we
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# backfill and try to fill in the history. This is an arbitrarily picked number so feel
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# free to tune it in the future.
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BACKFILL_BECAUSE_TOO_MANY_GAPS_THRESHOLD = 3
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# This is used to avoid purging a room several time at the same moment,
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# and also paginating during a purge. Pagination can trigger backfill,
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# which would create old events locally, and would potentially clash with the room delete.
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PURGE_PAGINATION_LOCK_NAME = "purge_pagination_lock"
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PURGE_HISTORY_ACTION_NAME = "purge_history"
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PURGE_ROOM_ACTION_NAME = "purge_room"
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SHUTDOWN_AND_PURGE_ROOM_ACTION_NAME = "shutdown_and_purge_room"
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class PaginationHandler:
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    """Handles pagination and purge history requests.
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    These are in the same handler due to the fact we need to block clients
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    paginating during a purge.
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    """
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    def __init__(self, hs: "HomeServer"):
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        self.hs = hs
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        self.auth = hs.get_auth()
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        self.store = hs.get_datastores().main
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        self._storage_controllers = hs.get_storage_controllers()
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        self._state_storage_controller = self._storage_controllers.state
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        self.clock = hs.get_clock()
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        self._server_name = hs.hostname
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        self._room_shutdown_handler = hs.get_room_shutdown_handler()
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        self._relations_handler = hs.get_relations_handler()
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        self._worker_locks = hs.get_worker_locks_handler()
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        self._task_scheduler = hs.get_task_scheduler()
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        self.pagination_lock = ReadWriteLock()
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        # IDs of rooms in which there currently an active purge *or delete* operation.
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        self._purges_in_progress_by_room: Set[str] = set()
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        self._event_serializer = hs.get_event_client_serializer()
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        self._retention_default_max_lifetime = (
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            hs.config.retention.retention_default_max_lifetime
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        )
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        self._retention_allowed_lifetime_min = (
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            hs.config.retention.retention_allowed_lifetime_min
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        )
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        self._retention_allowed_lifetime_max = (
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            hs.config.retention.retention_allowed_lifetime_max
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        )
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        self._forgotten_room_retention_period = (
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            hs.config.server.forgotten_room_retention_period
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        )
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        self._is_master = hs.config.worker.worker_app is None
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        if hs.config.retention.retention_enabled and self._is_master:
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            # Run the purge jobs described in the configuration file.
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            for job in hs.config.retention.retention_purge_jobs:
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                logger.info("Setting up purge job with config: %s", job)
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                self.clock.looping_call(
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                    run_as_background_process,
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                    job.interval,
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                    "purge_history_for_rooms_in_range",
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                    self.purge_history_for_rooms_in_range,
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                    job.shortest_max_lifetime,
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                    job.longest_max_lifetime,
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                )
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        self._task_scheduler.register_action(
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            self._purge_history, PURGE_HISTORY_ACTION_NAME
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        )
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        self._task_scheduler.register_action(self._purge_room, PURGE_ROOM_ACTION_NAME)
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        self._task_scheduler.register_action(
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            self._shutdown_and_purge_room, SHUTDOWN_AND_PURGE_ROOM_ACTION_NAME
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        )
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    async def purge_history_for_rooms_in_range(
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        self, min_ms: Optional[int], max_ms: Optional[int]
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    ) -> None:
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        """Purge outdated events from rooms within the given retention range.
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        If a default retention policy is defined in the server's configuration and its
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        'max_lifetime' is within this range, also targets rooms which don't have a
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        retention policy.
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        Args:
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            min_ms: Duration in milliseconds that define the lower limit of
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                the range to handle (exclusive). If None, it means that the range has no
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                lower limit.
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            max_ms: Duration in milliseconds that define the upper limit of
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                the range to handle (inclusive). If None, it means that the range has no
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                upper limit.
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        """
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        # We want the storage layer to include rooms with no retention policy in its
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        # return value only if a default retention policy is defined in the server's
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        # configuration and that policy's 'max_lifetime' is either lower (or equal) than
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        # max_ms or higher than min_ms (or both).
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        if self._retention_default_max_lifetime is not None:
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            include_null = True
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            if min_ms is not None and min_ms >= self._retention_default_max_lifetime:
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                # The default max_lifetime is lower than (or equal to) min_ms.
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                include_null = False
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            if max_ms is not None and max_ms < self._retention_default_max_lifetime:
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                # The default max_lifetime is higher than max_ms.
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                include_null = False
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        else:
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            include_null = False
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        logger.info(
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            "[purge] Running retention purge job for %s < max_lifetime <= %s (include NULLs = %s)",
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            min_ms,
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            max_ms,
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            include_null,
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        )
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        rooms = await self.store.get_rooms_for_retention_period_in_range(
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            min_ms, max_ms, include_null
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        )
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        logger.debug("[purge] Rooms to purge: %s", rooms)
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        for room_id, retention_policy in rooms.items():
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            logger.info("[purge] Attempting to purge messages in room %s", room_id)
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            if len(await self.get_delete_tasks_by_room(room_id, only_active=True)) > 0:
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                logger.warning(
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                    "[purge] not purging room %s for retention as there's an ongoing purge"
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                    " running for this room",
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                    room_id,
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                )
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                continue
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            # If max_lifetime is None, it means that the room has no retention policy.
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            # Given we only retrieve such rooms when there's a default retention policy
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            # defined in the server's configuration, we can safely assume that's the
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            # case and use it for this room.
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            max_lifetime = (
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                retention_policy.max_lifetime or self._retention_default_max_lifetime
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            )
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            # Cap the effective max_lifetime to be within the range allowed in the
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            # config.
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            # We do this in two steps:
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            #   1. Make sure it's higher or equal to the minimum allowed value, and if
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            #      it's not replace it with that value. This is because the server
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            #      operator can be required to not delete information before a given
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            #      time, e.g. to comply with freedom of information laws.
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            #   2. Make sure the resulting value is lower or equal to the maximum allowed
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            #      value, and if it's not replace it with that value. This is because the
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            #      server operator can be required to delete any data after a specific
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            #      amount of time.
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            if self._retention_allowed_lifetime_min is not None:
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                max_lifetime = max(self._retention_allowed_lifetime_min, max_lifetime)
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            if self._retention_allowed_lifetime_max is not None:
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                max_lifetime = min(max_lifetime, self._retention_allowed_lifetime_max)
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            logger.debug("[purge] max_lifetime for room %s: %s", room_id, max_lifetime)
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            # Figure out what token we should start purging at.
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            ts = self.clock.time_msec() - max_lifetime
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            stream_ordering = await self.store.find_first_stream_ordering_after_ts(ts)
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            r = await self.store.get_room_event_before_stream_ordering(
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                room_id,
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                stream_ordering,
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            )
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            if not r:
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                logger.warning(
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                    "[purge] purging events not possible: No event found "
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                    "(ts %i => stream_ordering %i)",
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                    ts,
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                    stream_ordering,
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                )
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                continue
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            (stream, topo, _event_id) = r
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            token = "t%d-%d" % (topo, stream)
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            logger.info("Starting purging events in room %s", room_id)
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            # We want to purge everything, including local events, and to run the purge in
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            # the background so that it's not blocking any other operation apart from
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            # other purges in the same room.
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            run_as_background_process(
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                PURGE_HISTORY_ACTION_NAME,
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                self.purge_history,
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                room_id,
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                token,
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                True,
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            )
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    async def start_purge_history(
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        self, room_id: str, token: str, delete_local_events: bool = False
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    ) -> str:
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        """Start off a history purge on a room.
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        Args:
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            room_id: The room to purge from
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            token: topological token to delete events before
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            delete_local_events: True to delete local events as well as
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                remote ones
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        Returns:
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            unique ID for this purge transaction.
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        """
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        purge_id = await self._task_scheduler.schedule_task(
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            PURGE_HISTORY_ACTION_NAME,
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            resource_id=room_id,
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            params={"token": token, "delete_local_events": delete_local_events},
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        )
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        # we log the purge_id here so that it can be tied back to the
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        # request id in the log lines.
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        logger.info("[purge] starting purge_id %s", purge_id)
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        return purge_id
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    async def _purge_history(
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        self,
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        task: ScheduledTask,
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    ) -> Tuple[TaskStatus, Optional[JsonMapping], Optional[str]]:
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        """
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        Scheduler action to purge some history of a room.
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        """
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        if (
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            task.resource_id is None
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            or task.params is None
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            or "token" not in task.params
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            or "delete_local_events" not in task.params
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        ):
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            return (
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                TaskStatus.FAILED,
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                None,
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                "Not enough parameters passed to _purge_history",
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            )
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        err = await self.purge_history(
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            task.resource_id,
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            task.params["token"],
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            task.params["delete_local_events"],
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        )
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        if err is not None:
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            return TaskStatus.FAILED, None, err
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        return TaskStatus.COMPLETE, None, None
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    async def purge_history(
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        self,
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        room_id: str,
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        token: str,
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        delete_local_events: bool,
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    ) -> Optional[str]:
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        """Carry out a history purge on a room.
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        Args:
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            room_id: The room to purge from
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            token: topological token to delete events before
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            delete_local_events: True to delete local events as well as remote ones
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        """
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        try:
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            async with self._worker_locks.acquire_read_write_lock(
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                PURGE_PAGINATION_LOCK_NAME, room_id, write=True
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            ):
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                await self._storage_controllers.purge_events.purge_history(
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                    room_id, token, delete_local_events
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                )
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            logger.info("[purge] complete")
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            return None
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        except Exception:
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            f = Failure()
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            logger.error(
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                "[purge] failed", exc_info=(f.type, f.value, f.getTracebackObject())
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            )
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            return f.getErrorMessage()
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    async def get_delete_task(self, delete_id: str) -> Optional[ScheduledTask]:
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        """Get the current status of an active deleting
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        Args:
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            delete_id: delete_id returned by start_shutdown_and_purge_room
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                or start_purge_history.
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        """
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        return await self._task_scheduler.get_task(delete_id)
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    async def get_delete_tasks_by_room(
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        self, room_id: str, only_active: Optional[bool] = False
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    ) -> List[ScheduledTask]:
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        """Get complete, failed or active delete tasks by room
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        Args:
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            room_id: room_id that is deleted
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            only_active: if True, completed&failed tasks will be omitted
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        """
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        statuses = [TaskStatus.ACTIVE]
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        if not only_active:
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            statuses += [TaskStatus.COMPLETE, TaskStatus.FAILED]
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        return await self._task_scheduler.get_tasks(
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            actions=[PURGE_ROOM_ACTION_NAME, SHUTDOWN_AND_PURGE_ROOM_ACTION_NAME],
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            resource_id=room_id,
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            statuses=statuses,
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        )
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    async def _purge_room(
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        self,
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        task: ScheduledTask,
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    ) -> Tuple[TaskStatus, Optional[JsonMapping], Optional[str]]:
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        """
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        Scheduler action to purge a room.
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        """
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        if not task.resource_id:
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            raise Exception("No room id passed to purge_room task")
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        params = task.params if task.params else {}
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        await self.purge_room(task.resource_id, params.get("force", False))
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        return TaskStatus.COMPLETE, None, None
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    async def purge_room(
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        self,
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        room_id: str,
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        force: bool,
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    ) -> None:
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        """Purge the given room from the database.
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        Args:
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            room_id: room to be purged
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            force: set true to skip checking for joined users.
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        """
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        logger.info("starting purge room_id=%s force=%s", room_id, force)
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        async with self._worker_locks.acquire_multi_read_write_lock(
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            [
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                (PURGE_PAGINATION_LOCK_NAME, room_id),
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                (NEW_EVENT_DURING_PURGE_LOCK_NAME, room_id),
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            ],
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            write=True,
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        ):
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            # first check that we have no users in this room
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            joined = await self.store.is_host_joined(room_id, self._server_name)
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            if joined:
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                if force:
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                    logger.info(
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                        "force-purging room %s with some local users still joined",
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                        room_id,
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                    )
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                else:
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                    raise SynapseError(400, "Users are still joined to this room")
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            await self._storage_controllers.purge_events.purge_room(room_id)
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        logger.info("purge complete for room_id %s", room_id)
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    @trace
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    async def get_messages(
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        self,
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        requester: Requester,
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        room_id: str,
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        pagin_config: PaginationConfig,
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        as_client_event: bool = True,
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        event_filter: Optional[Filter] = None,
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        use_admin_priviledge: bool = False,
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    ) -> JsonDict:
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        """Get messages in a room.
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        Args:
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            requester: The user requesting messages.
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            room_id: The room they want messages from.
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            pagin_config: The pagination config rules to apply, if any.
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            as_client_event: True to get events in client-server format.
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            event_filter: Filter to apply to results or None
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            use_admin_priviledge: if `True`, return all events, regardless
 | 
						|
                of whether `user` has access to them. To be used **ONLY**
 | 
						|
                from the admin API.
 | 
						|
 | 
						|
        Returns:
 | 
						|
            Pagination API results
 | 
						|
        """
 | 
						|
        if use_admin_priviledge:
 | 
						|
            await assert_user_is_admin(self.auth, requester)
 | 
						|
 | 
						|
        user_id = requester.user.to_string()
 | 
						|
 | 
						|
        if pagin_config.from_token:
 | 
						|
            from_token = pagin_config.from_token
 | 
						|
        elif pagin_config.direction == Direction.FORWARDS:
 | 
						|
            from_token = (
 | 
						|
                await self.hs.get_event_sources().get_start_token_for_pagination(
 | 
						|
                    room_id
 | 
						|
                )
 | 
						|
            )
 | 
						|
        else:
 | 
						|
            from_token = (
 | 
						|
                await self.hs.get_event_sources().get_current_token_for_pagination(
 | 
						|
                    room_id
 | 
						|
                )
 | 
						|
            )
 | 
						|
            # We expect `/messages` to use historic pagination tokens by default but
 | 
						|
            # `/messages` should still works with live tokens when manually provided.
 | 
						|
            assert from_token.room_key.topological is not None
 | 
						|
 | 
						|
        room_token = from_token.room_key
 | 
						|
 | 
						|
        (membership, member_event_id) = (None, None)
 | 
						|
        if not use_admin_priviledge:
 | 
						|
            (
 | 
						|
                membership,
 | 
						|
                member_event_id,
 | 
						|
            ) = await self.auth.check_user_in_room_or_world_readable(
 | 
						|
                room_id, requester, allow_departed_users=True
 | 
						|
            )
 | 
						|
 | 
						|
        if pagin_config.direction == Direction.BACKWARDS:
 | 
						|
            # if we're going backwards, we might need to backfill. This
 | 
						|
            # requires that we have a topo token.
 | 
						|
            if room_token.topological:
 | 
						|
                curr_topo = room_token.topological
 | 
						|
            else:
 | 
						|
                curr_topo = await self.store.get_current_topological_token(
 | 
						|
                    room_id, room_token.stream
 | 
						|
                )
 | 
						|
 | 
						|
        # If they have left the room then clamp the token to be before
 | 
						|
        # they left the room, to save the effort of loading from the
 | 
						|
        # database.
 | 
						|
        if (
 | 
						|
            pagin_config.direction == Direction.BACKWARDS
 | 
						|
            and not use_admin_priviledge
 | 
						|
            and membership == Membership.LEAVE
 | 
						|
        ):
 | 
						|
            # This is only None if the room is world_readable, in which case
 | 
						|
            # "Membership.JOIN" would have been returned and we should never hit
 | 
						|
            # this branch.
 | 
						|
            assert member_event_id
 | 
						|
 | 
						|
            leave_token = await self.store.get_topological_token_for_event(
 | 
						|
                member_event_id
 | 
						|
            )
 | 
						|
            assert leave_token.topological is not None
 | 
						|
 | 
						|
            if leave_token.topological < curr_topo:
 | 
						|
                from_token = from_token.copy_and_replace(
 | 
						|
                    StreamKeyType.ROOM, leave_token
 | 
						|
                )
 | 
						|
 | 
						|
        to_room_key = None
 | 
						|
        if pagin_config.to_token:
 | 
						|
            to_room_key = pagin_config.to_token.room_key
 | 
						|
 | 
						|
        # Initially fetch the events from the database. With any luck, we can return
 | 
						|
        # these without blocking on backfill (handled below).
 | 
						|
        events, next_key = await self.store.paginate_room_events(
 | 
						|
            room_id=room_id,
 | 
						|
            from_key=from_token.room_key,
 | 
						|
            to_key=to_room_key,
 | 
						|
            direction=pagin_config.direction,
 | 
						|
            limit=pagin_config.limit,
 | 
						|
            event_filter=event_filter,
 | 
						|
        )
 | 
						|
 | 
						|
        if pagin_config.direction == Direction.BACKWARDS:
 | 
						|
            # We use a `Set` because there can be multiple events at a given depth
 | 
						|
            # and we only care about looking at the unique continum of depths to
 | 
						|
            # find gaps.
 | 
						|
            event_depths: Set[int] = {event.depth for event in events}
 | 
						|
            sorted_event_depths = sorted(event_depths)
 | 
						|
 | 
						|
            # Inspect the depths of the returned events to see if there are any gaps
 | 
						|
            found_big_gap = False
 | 
						|
            number_of_gaps = 0
 | 
						|
            previous_event_depth = (
 | 
						|
                sorted_event_depths[0] if len(sorted_event_depths) > 0 else 0
 | 
						|
            )
 | 
						|
            for event_depth in sorted_event_depths:
 | 
						|
                # We don't expect a negative depth but we'll just deal with it in
 | 
						|
                # any case by taking the absolute value to get the true gap between
 | 
						|
                # any two integers.
 | 
						|
                depth_gap = abs(event_depth - previous_event_depth)
 | 
						|
                # A `depth_gap` of 1 is a normal continuous chain to the next event
 | 
						|
                # (1 <-- 2 <-- 3) so anything larger indicates a missing event (it's
 | 
						|
                # also possible there is no event at a given depth but we can't ever
 | 
						|
                # know that for sure)
 | 
						|
                if depth_gap > 1:
 | 
						|
                    number_of_gaps += 1
 | 
						|
 | 
						|
                # We only tolerate a small number single-event long gaps in the
 | 
						|
                # returned events because those are most likely just events we've
 | 
						|
                # failed to pull in the past. Anything longer than that is probably
 | 
						|
                # a sign that we're missing a decent chunk of history and we should
 | 
						|
                # try to backfill it.
 | 
						|
                #
 | 
						|
                # XXX: It's possible we could tolerate longer gaps if we checked
 | 
						|
                # that a given events `prev_events` is one that has failed pull
 | 
						|
                # attempts and we could just treat it like a dead branch of history
 | 
						|
                # for now or at least something that we don't need the block the
 | 
						|
                # client on to try pulling.
 | 
						|
                #
 | 
						|
                # XXX: If we had something like MSC3871 to indicate gaps in the
 | 
						|
                # timeline to the client, we could also get away with any sized gap
 | 
						|
                # and just have the client refetch the holes as they see fit.
 | 
						|
                if depth_gap > 2:
 | 
						|
                    found_big_gap = True
 | 
						|
                    break
 | 
						|
                previous_event_depth = event_depth
 | 
						|
 | 
						|
            # Backfill in the foreground if we found a big gap, have too many holes,
 | 
						|
            # or we don't have enough events to fill the limit that the client asked
 | 
						|
            # for.
 | 
						|
            missing_too_many_events = (
 | 
						|
                number_of_gaps > BACKFILL_BECAUSE_TOO_MANY_GAPS_THRESHOLD
 | 
						|
            )
 | 
						|
            not_enough_events_to_fill_response = len(events) < pagin_config.limit
 | 
						|
            if (
 | 
						|
                found_big_gap
 | 
						|
                or missing_too_many_events
 | 
						|
                or not_enough_events_to_fill_response
 | 
						|
            ):
 | 
						|
                did_backfill = await self.hs.get_federation_handler().maybe_backfill(
 | 
						|
                    room_id,
 | 
						|
                    curr_topo,
 | 
						|
                    limit=pagin_config.limit,
 | 
						|
                )
 | 
						|
 | 
						|
                # If we did backfill something, refetch the events from the database to
 | 
						|
                # catch anything new that might have been added since we last fetched.
 | 
						|
                if did_backfill:
 | 
						|
                    events, next_key = await self.store.paginate_room_events(
 | 
						|
                        room_id=room_id,
 | 
						|
                        from_key=from_token.room_key,
 | 
						|
                        to_key=to_room_key,
 | 
						|
                        direction=pagin_config.direction,
 | 
						|
                        limit=pagin_config.limit,
 | 
						|
                        event_filter=event_filter,
 | 
						|
                    )
 | 
						|
            else:
 | 
						|
                # Otherwise, we can backfill in the background for eventual
 | 
						|
                # consistency's sake but we don't need to block the client waiting
 | 
						|
                # for a costly federation call and processing.
 | 
						|
                run_as_background_process(
 | 
						|
                    "maybe_backfill_in_the_background",
 | 
						|
                    self.hs.get_federation_handler().maybe_backfill,
 | 
						|
                    room_id,
 | 
						|
                    curr_topo,
 | 
						|
                    limit=pagin_config.limit,
 | 
						|
                )
 | 
						|
 | 
						|
        next_token = from_token.copy_and_replace(StreamKeyType.ROOM, next_key)
 | 
						|
 | 
						|
        # if no events are returned from pagination, that implies
 | 
						|
        # we have reached the end of the available events.
 | 
						|
        # In that case we do not return end, to tell the client
 | 
						|
        # there is no need for further queries.
 | 
						|
        if not events:
 | 
						|
            return {
 | 
						|
                "chunk": [],
 | 
						|
                "start": await from_token.to_string(self.store),
 | 
						|
            }
 | 
						|
 | 
						|
        if event_filter:
 | 
						|
            events = await event_filter.filter(events)
 | 
						|
 | 
						|
        if not use_admin_priviledge:
 | 
						|
            events = await filter_events_for_client(
 | 
						|
                self._storage_controllers,
 | 
						|
                user_id,
 | 
						|
                events,
 | 
						|
                is_peeking=(member_event_id is None),
 | 
						|
            )
 | 
						|
 | 
						|
        # if after the filter applied there are no more events
 | 
						|
        # return immediately - but there might be more in next_token batch
 | 
						|
        if not events:
 | 
						|
            return {
 | 
						|
                "chunk": [],
 | 
						|
                "start": await from_token.to_string(self.store),
 | 
						|
                "end": await next_token.to_string(self.store),
 | 
						|
            }
 | 
						|
 | 
						|
        state = None
 | 
						|
        if event_filter and event_filter.lazy_load_members and len(events) > 0:
 | 
						|
            # TODO: remove redundant members
 | 
						|
 | 
						|
            # FIXME: we also care about invite targets etc.
 | 
						|
            state_filter = StateFilter.from_types(
 | 
						|
                (EventTypes.Member, event.sender) for event in events
 | 
						|
            )
 | 
						|
 | 
						|
            state_ids = await self._state_storage_controller.get_state_ids_for_event(
 | 
						|
                events[0].event_id, state_filter=state_filter
 | 
						|
            )
 | 
						|
 | 
						|
            if state_ids:
 | 
						|
                state_dict = await self.store.get_events(list(state_ids.values()))
 | 
						|
                state = state_dict.values()
 | 
						|
 | 
						|
        aggregations = await self._relations_handler.get_bundled_aggregations(
 | 
						|
            events, user_id
 | 
						|
        )
 | 
						|
 | 
						|
        time_now = self.clock.time_msec()
 | 
						|
 | 
						|
        serialize_options = SerializeEventConfig(
 | 
						|
            as_client_event=as_client_event, requester=requester
 | 
						|
        )
 | 
						|
 | 
						|
        chunk = {
 | 
						|
            "chunk": (
 | 
						|
                await self._event_serializer.serialize_events(
 | 
						|
                    events,
 | 
						|
                    time_now,
 | 
						|
                    config=serialize_options,
 | 
						|
                    bundle_aggregations=aggregations,
 | 
						|
                )
 | 
						|
            ),
 | 
						|
            "start": await from_token.to_string(self.store),
 | 
						|
            "end": await next_token.to_string(self.store),
 | 
						|
        }
 | 
						|
 | 
						|
        if state:
 | 
						|
            chunk["state"] = await self._event_serializer.serialize_events(
 | 
						|
                state, time_now, config=serialize_options
 | 
						|
            )
 | 
						|
 | 
						|
        return chunk
 | 
						|
 | 
						|
    async def _shutdown_and_purge_room(
 | 
						|
        self,
 | 
						|
        task: ScheduledTask,
 | 
						|
    ) -> Tuple[TaskStatus, Optional[JsonMapping], Optional[str]]:
 | 
						|
        """
 | 
						|
        Scheduler action to shutdown and purge a room.
 | 
						|
        """
 | 
						|
        if task.resource_id is None or task.params is None:
 | 
						|
            raise Exception(
 | 
						|
                "No room id and/or no parameters passed to shutdown_and_purge_room task"
 | 
						|
            )
 | 
						|
 | 
						|
        room_id = task.resource_id
 | 
						|
 | 
						|
        async def update_result(result: Optional[JsonMapping]) -> None:
 | 
						|
            await self._task_scheduler.update_task(task.id, result=result)
 | 
						|
 | 
						|
        shutdown_result = (
 | 
						|
            cast(ShutdownRoomResponse, task.result) if task.result else None
 | 
						|
        )
 | 
						|
 | 
						|
        shutdown_result = await self._room_shutdown_handler.shutdown_room(
 | 
						|
            room_id,
 | 
						|
            cast(ShutdownRoomParams, task.params),
 | 
						|
            shutdown_result,
 | 
						|
            update_result,
 | 
						|
        )
 | 
						|
 | 
						|
        if task.params.get("purge", False):
 | 
						|
            await self.purge_room(
 | 
						|
                room_id,
 | 
						|
                task.params.get("force_purge", False),
 | 
						|
            )
 | 
						|
 | 
						|
        return (TaskStatus.COMPLETE, shutdown_result, None)
 | 
						|
 | 
						|
    async def start_shutdown_and_purge_room(
 | 
						|
        self,
 | 
						|
        room_id: str,
 | 
						|
        shutdown_params: ShutdownRoomParams,
 | 
						|
    ) -> str:
 | 
						|
        """Start off shut down and purge on a room.
 | 
						|
 | 
						|
        Args:
 | 
						|
            room_id: The ID of the room to shut down.
 | 
						|
            shutdown_params: parameters for the shutdown
 | 
						|
 | 
						|
        Returns:
 | 
						|
            unique ID for this delete transaction.
 | 
						|
        """
 | 
						|
        if len(await self.get_delete_tasks_by_room(room_id, only_active=True)) > 0:
 | 
						|
            raise SynapseError(400, "Purge already in progress for %s" % (room_id,))
 | 
						|
 | 
						|
        # This check is double to `RoomShutdownHandler.shutdown_room`
 | 
						|
        # But here the requester get a direct response / error with HTTP request
 | 
						|
        # and do not have to check the purge status
 | 
						|
        new_room_user_id = shutdown_params["new_room_user_id"]
 | 
						|
        if new_room_user_id is not None:
 | 
						|
            if not self.hs.is_mine_id(new_room_user_id):
 | 
						|
                raise SynapseError(
 | 
						|
                    400, "User must be our own: %s" % (new_room_user_id,)
 | 
						|
                )
 | 
						|
 | 
						|
        delete_id = await self._task_scheduler.schedule_task(
 | 
						|
            SHUTDOWN_AND_PURGE_ROOM_ACTION_NAME,
 | 
						|
            resource_id=room_id,
 | 
						|
            params=shutdown_params,
 | 
						|
        )
 | 
						|
 | 
						|
        # we log the delete_id here so that it can be tied back to the
 | 
						|
        # request id in the log lines.
 | 
						|
        logger.info(
 | 
						|
            "starting shutdown room_id %s with delete_id %s",
 | 
						|
            room_id,
 | 
						|
            delete_id,
 | 
						|
        )
 | 
						|
 | 
						|
        return delete_id
 |