1956 lines
77 KiB
Python
1956 lines
77 KiB
Python
# Copyright 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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import threading
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from typing import (
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TYPE_CHECKING,
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Any,
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Collection,
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Container,
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Dict,
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Iterable,
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List,
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NoReturn,
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Optional,
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Set,
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Tuple,
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cast,
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overload,
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)
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import attr
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from constantly import NamedConstant, Names
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from prometheus_client import Gauge
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from typing_extensions import Literal
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from twisted.internet import defer
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from synapse.api.constants import EventTypes
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from synapse.api.errors import NotFoundError, SynapseError
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from synapse.api.room_versions import (
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KNOWN_ROOM_VERSIONS,
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EventFormatVersions,
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RoomVersion,
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RoomVersions,
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)
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from synapse.events import EventBase, make_event_from_dict
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from synapse.events.snapshot import EventContext
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from synapse.events.utils import prune_event
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from synapse.logging.context import (
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PreserveLoggingContext,
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current_context,
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make_deferred_yieldable,
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)
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from synapse.metrics.background_process_metrics import (
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run_as_background_process,
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wrap_as_background_process,
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)
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from synapse.replication.slave.storage._slaved_id_tracker import SlavedIdTracker
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from synapse.replication.tcp.streams import BackfillStream
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from synapse.replication.tcp.streams.events import EventsStream
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from synapse.storage._base import SQLBaseStore, db_to_json, make_in_list_sql_clause
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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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)
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from synapse.storage.engines import PostgresEngine
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from synapse.storage.types import Cursor
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from synapse.storage.util.id_generators import (
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AbstractStreamIdTracker,
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MultiWriterIdGenerator,
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StreamIdGenerator,
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)
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from synapse.storage.util.sequence import build_sequence_generator
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from synapse.types import JsonDict, get_domain_from_id
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from synapse.util import unwrapFirstError
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from synapse.util.async_helpers import ObservableDeferred
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from synapse.util.caches.descriptors import cached, cachedList
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from synapse.util.caches.lrucache import LruCache
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from synapse.util.iterutils import batch_iter
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from synapse.util.metrics import Measure
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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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# These values are used in the `enqueue_event` and `_fetch_loop` methods to
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# control how we batch/bulk fetch events from the database.
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# The values are plucked out of thing air to make initial sync run faster
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# on jki.re
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# TODO: Make these configurable.
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EVENT_QUEUE_THREADS = 3 # Max number of threads that will fetch events
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EVENT_QUEUE_ITERATIONS = 3 # No. times we block waiting for requests for events
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EVENT_QUEUE_TIMEOUT_S = 0.1 # Timeout when waiting for requests for events
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event_fetch_ongoing_gauge = Gauge(
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"synapse_event_fetch_ongoing",
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"The number of event fetchers that are running",
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)
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@attr.s(slots=True, auto_attribs=True)
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class EventCacheEntry:
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event: EventBase
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redacted_event: Optional[EventBase]
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@attr.s(slots=True, frozen=True, auto_attribs=True)
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class _EventRow:
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"""
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An event, as pulled from the database.
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Properties:
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event_id: The event ID of the event.
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stream_ordering: stream ordering for this event
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json: json-encoded event structure
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internal_metadata: json-encoded internal metadata dict
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format_version: The format of the event. Hopefully one of EventFormatVersions.
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'None' means the event predates EventFormatVersions (so the event is format V1).
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room_version_id: The version of the room which contains the event. Hopefully
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one of RoomVersions.
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Due to historical reasons, there may be a few events in the database which
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do not have an associated room; in this case None will be returned here.
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rejected_reason: if the event was rejected, the reason why.
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redactions: a list of event-ids which (claim to) redact this event.
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outlier: True if this event is an outlier.
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"""
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event_id: str
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stream_ordering: int
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json: str
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internal_metadata: str
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format_version: Optional[int]
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room_version_id: Optional[str]
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rejected_reason: Optional[str]
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redactions: List[str]
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outlier: bool
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class EventRedactBehaviour(Names):
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"""
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What to do when retrieving a redacted event from the database.
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"""
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AS_IS = NamedConstant()
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REDACT = NamedConstant()
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BLOCK = NamedConstant()
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class EventsWorkerStore(SQLBaseStore):
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# Whether to use dedicated DB threads for event fetching. This is only used
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# if there are multiple DB threads available. When used will lock the DB
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# thread for periods of time (so unit tests want to disable this when they
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# run DB transactions on the main thread). See EVENT_QUEUE_* for more
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# options controlling this.
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USE_DEDICATED_DB_THREADS_FOR_EVENT_FETCHING = True
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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._stream_id_gen: AbstractStreamIdTracker
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self._backfill_id_gen: AbstractStreamIdTracker
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if isinstance(database.engine, PostgresEngine):
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# If we're using Postgres than we can use `MultiWriterIdGenerator`
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# regardless of whether this process writes to the streams or not.
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self._stream_id_gen = MultiWriterIdGenerator(
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db_conn=db_conn,
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db=database,
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stream_name="events",
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instance_name=hs.get_instance_name(),
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tables=[("events", "instance_name", "stream_ordering")],
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sequence_name="events_stream_seq",
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writers=hs.config.worker.writers.events,
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)
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self._backfill_id_gen = MultiWriterIdGenerator(
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db_conn=db_conn,
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db=database,
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stream_name="backfill",
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instance_name=hs.get_instance_name(),
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tables=[("events", "instance_name", "stream_ordering")],
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sequence_name="events_backfill_stream_seq",
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positive=False,
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writers=hs.config.worker.writers.events,
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)
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else:
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# We shouldn't be running in worker mode with SQLite, but its useful
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# to support it for unit tests.
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#
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# If this process is the writer than we need to use
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# `StreamIdGenerator`, otherwise we use `SlavedIdTracker` which gets
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# updated over replication. (Multiple writers are not supported for
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# SQLite).
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if hs.get_instance_name() in hs.config.worker.writers.events:
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self._stream_id_gen = StreamIdGenerator(
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db_conn,
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"events",
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"stream_ordering",
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)
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self._backfill_id_gen = StreamIdGenerator(
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db_conn,
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"events",
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"stream_ordering",
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step=-1,
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extra_tables=[("ex_outlier_stream", "event_stream_ordering")],
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)
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else:
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self._stream_id_gen = SlavedIdTracker(
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db_conn, "events", "stream_ordering"
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)
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self._backfill_id_gen = SlavedIdTracker(
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db_conn, "events", "stream_ordering", step=-1
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)
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if hs.config.worker.run_background_tasks:
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# We periodically clean out old transaction ID mappings
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self._clock.looping_call(
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self._cleanup_old_transaction_ids,
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5 * 60 * 1000,
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)
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self._get_event_cache: LruCache[Tuple[str], EventCacheEntry] = LruCache(
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cache_name="*getEvent*",
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max_size=hs.config.caches.event_cache_size,
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)
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# Map from event ID to a deferred that will result in a map from event
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# ID to cache entry. Note that the returned dict may not have the
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# requested event in it if the event isn't in the DB.
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self._current_event_fetches: Dict[
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str, ObservableDeferred[Dict[str, EventCacheEntry]]
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] = {}
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self._event_fetch_lock = threading.Condition()
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self._event_fetch_list: List[
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Tuple[Iterable[str], "defer.Deferred[Dict[str, _EventRow]]"]
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] = []
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self._event_fetch_ongoing = 0
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event_fetch_ongoing_gauge.set(self._event_fetch_ongoing)
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# We define this sequence here so that it can be referenced from both
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# the DataStore and PersistEventStore.
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def get_chain_id_txn(txn: Cursor) -> int:
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txn.execute("SELECT COALESCE(max(chain_id), 0) FROM event_auth_chains")
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return cast(Tuple[int], txn.fetchone())[0]
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self.event_chain_id_gen = build_sequence_generator(
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db_conn,
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database.engine,
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get_chain_id_txn,
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"event_auth_chain_id",
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table="event_auth_chains",
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id_column="chain_id",
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)
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def process_replication_rows(
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self,
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stream_name: str,
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instance_name: str,
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token: int,
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rows: Iterable[Any],
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) -> None:
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if stream_name == EventsStream.NAME:
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self._stream_id_gen.advance(instance_name, token)
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elif stream_name == BackfillStream.NAME:
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self._backfill_id_gen.advance(instance_name, -token)
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super().process_replication_rows(stream_name, instance_name, token, rows)
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async def get_received_ts(self, event_id: str) -> Optional[int]:
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"""Get received_ts (when it was persisted) for the event.
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Raises an exception for unknown events.
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Args:
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event_id: The event ID to query.
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Returns:
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Timestamp in milliseconds, or None for events that were persisted
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before received_ts was implemented.
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"""
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return await self.db_pool.simple_select_one_onecol(
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table="events",
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keyvalues={"event_id": event_id},
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retcol="received_ts",
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desc="get_received_ts",
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)
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# Inform mypy that if allow_none is False (the default) then get_event
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# always returns an EventBase.
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@overload
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async def get_event(
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self,
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event_id: str,
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redact_behaviour: EventRedactBehaviour = EventRedactBehaviour.REDACT,
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get_prev_content: bool = ...,
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allow_rejected: bool = ...,
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allow_none: Literal[False] = ...,
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check_room_id: Optional[str] = ...,
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) -> EventBase:
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...
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@overload
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async def get_event(
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self,
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event_id: str,
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redact_behaviour: EventRedactBehaviour = EventRedactBehaviour.REDACT,
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get_prev_content: bool = ...,
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allow_rejected: bool = ...,
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allow_none: Literal[True] = ...,
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check_room_id: Optional[str] = ...,
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) -> Optional[EventBase]:
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...
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async def get_event(
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self,
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event_id: str,
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redact_behaviour: EventRedactBehaviour = EventRedactBehaviour.REDACT,
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get_prev_content: bool = False,
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allow_rejected: bool = False,
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allow_none: bool = False,
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check_room_id: Optional[str] = None,
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) -> Optional[EventBase]:
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"""Get an event from the database by event_id.
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Args:
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event_id: The event_id of the event to fetch
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redact_behaviour: Determine what to do with a redacted event. Possible values:
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* AS_IS - Return the full event body with no redacted content
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* REDACT - Return the event but with a redacted body
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* DISALLOW - Do not return redacted events (behave as per allow_none
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if the event is redacted)
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get_prev_content: If True and event is a state event,
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include the previous states content in the unsigned field.
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allow_rejected: If True, return rejected events. Otherwise,
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behave as per allow_none.
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allow_none: If True, return None if no event found, if
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False throw a NotFoundError
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check_room_id: if not None, check the room of the found event.
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If there is a mismatch, behave as per allow_none.
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Returns:
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The event, or None if the event was not found.
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"""
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if not isinstance(event_id, str):
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raise TypeError("Invalid event event_id %r" % (event_id,))
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events = await self.get_events_as_list(
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[event_id],
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redact_behaviour=redact_behaviour,
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get_prev_content=get_prev_content,
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allow_rejected=allow_rejected,
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)
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event = events[0] if events else None
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if event is not None and check_room_id is not None:
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if event.room_id != check_room_id:
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event = None
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if event is None and not allow_none:
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raise NotFoundError("Could not find event %s" % (event_id,))
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return event
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async def get_events(
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self,
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event_ids: Collection[str],
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redact_behaviour: EventRedactBehaviour = EventRedactBehaviour.REDACT,
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get_prev_content: bool = False,
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allow_rejected: bool = False,
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) -> Dict[str, EventBase]:
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"""Get events from the database
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Args:
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event_ids: The event_ids of the events to fetch
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redact_behaviour: Determine what to do with a redacted event. Possible
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values:
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* AS_IS - Return the full event body with no redacted content
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* REDACT - Return the event but with a redacted body
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* DISALLOW - Do not return redacted events (omit them from the response)
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get_prev_content: If True and event is a state event,
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include the previous states content in the unsigned field.
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allow_rejected: If True, return rejected events. Otherwise,
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omits rejeted events from the response.
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Returns:
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A mapping from event_id to event.
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"""
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events = await self.get_events_as_list(
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event_ids,
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redact_behaviour=redact_behaviour,
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get_prev_content=get_prev_content,
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allow_rejected=allow_rejected,
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)
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return {e.event_id: e for e in events}
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async def get_events_as_list(
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self,
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event_ids: Collection[str],
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redact_behaviour: EventRedactBehaviour = EventRedactBehaviour.REDACT,
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get_prev_content: bool = False,
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allow_rejected: bool = False,
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) -> List[EventBase]:
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"""Get events from the database and return in a list in the same order
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as given by `event_ids` arg.
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Unknown events will be omitted from the response.
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Args:
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event_ids: The event_ids of the events to fetch
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redact_behaviour: Determine what to do with a redacted event. Possible values:
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* AS_IS - Return the full event body with no redacted content
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* REDACT - Return the event but with a redacted body
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* DISALLOW - Do not return redacted events (omit them from the response)
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get_prev_content: If True and event is a state event,
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include the previous states content in the unsigned field.
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allow_rejected: If True, return rejected events. Otherwise,
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omits rejected events from the response.
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Returns:
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List of events fetched from the database. The events are in the same
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order as `event_ids` arg.
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Note that the returned list may be smaller than the list of event
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IDs if not all events could be fetched.
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"""
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if not event_ids:
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return []
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# there may be duplicates so we cast the list to a set
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event_entry_map = await self._get_events_from_cache_or_db(
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set(event_ids), allow_rejected=allow_rejected
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)
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events = []
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for event_id in event_ids:
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entry = event_entry_map.get(event_id, None)
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if not entry:
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continue
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if not allow_rejected:
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assert not entry.event.rejected_reason, (
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"rejected event returned from _get_events_from_cache_or_db despite "
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"allow_rejected=False"
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)
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# We may not have had the original event when we received a redaction, so
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# we have to recheck auth now.
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if not allow_rejected and entry.event.type == EventTypes.Redaction:
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if entry.event.redacts is None:
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# A redacted redaction doesn't have a `redacts` key, in
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# which case lets just withhold the event.
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#
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# Note: Most of the time if the redactions has been
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# redacted we still have the un-redacted event in the DB
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# and so we'll still see the `redacts` key. However, this
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# isn't always true e.g. if we have censored the event.
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logger.debug(
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"Withholding redaction event %s as we don't have redacts key",
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event_id,
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)
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continue
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redacted_event_id = entry.event.redacts
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event_map = await self._get_events_from_cache_or_db([redacted_event_id])
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original_event_entry = event_map.get(redacted_event_id)
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if not original_event_entry:
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# we don't have the redacted event (or it was rejected).
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#
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# We assume that the redaction isn't authorized for now; if the
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# redacted event later turns up, the redaction will be re-checked,
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# and if it is found valid, the original will get redacted before it
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# is served to the client.
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logger.debug(
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"Withholding redaction event %s since we don't (yet) have the "
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"original %s",
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event_id,
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redacted_event_id,
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)
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continue
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original_event = original_event_entry.event
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if original_event.type == EventTypes.Create:
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# we never serve redactions of Creates to clients.
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logger.info(
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"Withholding redaction %s of create event %s",
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event_id,
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redacted_event_id,
|
|
)
|
|
continue
|
|
|
|
if original_event.room_id != entry.event.room_id:
|
|
logger.info(
|
|
"Withholding redaction %s of event %s from a different room",
|
|
event_id,
|
|
redacted_event_id,
|
|
)
|
|
continue
|
|
|
|
if entry.event.internal_metadata.need_to_check_redaction():
|
|
original_domain = get_domain_from_id(original_event.sender)
|
|
redaction_domain = get_domain_from_id(entry.event.sender)
|
|
if original_domain != redaction_domain:
|
|
# the senders don't match, so this is forbidden
|
|
logger.info(
|
|
"Withholding redaction %s whose sender domain %s doesn't "
|
|
"match that of redacted event %s %s",
|
|
event_id,
|
|
redaction_domain,
|
|
redacted_event_id,
|
|
original_domain,
|
|
)
|
|
continue
|
|
|
|
# Update the cache to save doing the checks again.
|
|
entry.event.internal_metadata.recheck_redaction = False
|
|
|
|
event = entry.event
|
|
|
|
if entry.redacted_event:
|
|
if redact_behaviour == EventRedactBehaviour.BLOCK:
|
|
# Skip this event
|
|
continue
|
|
elif redact_behaviour == EventRedactBehaviour.REDACT:
|
|
event = entry.redacted_event
|
|
|
|
events.append(event)
|
|
|
|
if get_prev_content:
|
|
if "replaces_state" in event.unsigned:
|
|
prev = await self.get_event(
|
|
event.unsigned["replaces_state"],
|
|
get_prev_content=False,
|
|
allow_none=True,
|
|
)
|
|
if prev:
|
|
event.unsigned = dict(event.unsigned)
|
|
event.unsigned["prev_content"] = prev.content
|
|
event.unsigned["prev_sender"] = prev.sender
|
|
|
|
return events
|
|
|
|
async def _get_events_from_cache_or_db(
|
|
self, event_ids: Iterable[str], allow_rejected: bool = False
|
|
) -> Dict[str, EventCacheEntry]:
|
|
"""Fetch a bunch of events from the cache or the database.
|
|
|
|
If events are pulled from the database, they will be cached for future lookups.
|
|
|
|
Unknown events are omitted from the response.
|
|
|
|
Args:
|
|
|
|
event_ids: The event_ids of the events to fetch
|
|
|
|
allow_rejected: Whether to include rejected events. If False,
|
|
rejected events are omitted from the response.
|
|
|
|
Returns:
|
|
map from event id to result
|
|
"""
|
|
event_entry_map = self._get_events_from_cache(
|
|
event_ids,
|
|
)
|
|
|
|
missing_events_ids = {e for e in event_ids if e not in event_entry_map}
|
|
|
|
# We now look up if we're already fetching some of the events in the DB,
|
|
# if so we wait for those lookups to finish instead of pulling the same
|
|
# events out of the DB multiple times.
|
|
#
|
|
# Note: we might get the same `ObservableDeferred` back for multiple
|
|
# events we're already fetching, so we deduplicate the deferreds to
|
|
# avoid extraneous work (if we don't do this we can end up in a n^2 mode
|
|
# when we wait on the same Deferred N times, then try and merge the
|
|
# same dict into itself N times).
|
|
already_fetching_ids: Set[str] = set()
|
|
already_fetching_deferreds: Set[
|
|
ObservableDeferred[Dict[str, EventCacheEntry]]
|
|
] = set()
|
|
|
|
for event_id in missing_events_ids:
|
|
deferred = self._current_event_fetches.get(event_id)
|
|
if deferred is not None:
|
|
# We're already pulling the event out of the DB. Add the deferred
|
|
# to the collection of deferreds to wait on.
|
|
already_fetching_ids.add(event_id)
|
|
already_fetching_deferreds.add(deferred)
|
|
|
|
missing_events_ids.difference_update(already_fetching_ids)
|
|
|
|
if missing_events_ids:
|
|
log_ctx = current_context()
|
|
log_ctx.record_event_fetch(len(missing_events_ids))
|
|
|
|
# Add entries to `self._current_event_fetches` for each event we're
|
|
# going to pull from the DB. We use a single deferred that resolves
|
|
# to all the events we pulled from the DB (this will result in this
|
|
# function returning more events than requested, but that can happen
|
|
# already due to `_get_events_from_db`).
|
|
fetching_deferred: ObservableDeferred[
|
|
Dict[str, EventCacheEntry]
|
|
] = ObservableDeferred(defer.Deferred(), consumeErrors=True)
|
|
for event_id in missing_events_ids:
|
|
self._current_event_fetches[event_id] = fetching_deferred
|
|
|
|
# Note that _get_events_from_db is also responsible for turning db rows
|
|
# into FrozenEvents (via _get_event_from_row), which involves seeing if
|
|
# the events have been redacted, and if so pulling the redaction event out
|
|
# of the database to check it.
|
|
#
|
|
try:
|
|
missing_events = await self._get_events_from_db(
|
|
missing_events_ids,
|
|
)
|
|
|
|
event_entry_map.update(missing_events)
|
|
except Exception as e:
|
|
with PreserveLoggingContext():
|
|
fetching_deferred.errback(e)
|
|
raise e
|
|
finally:
|
|
# Ensure that we mark these events as no longer being fetched.
|
|
for event_id in missing_events_ids:
|
|
self._current_event_fetches.pop(event_id, None)
|
|
|
|
with PreserveLoggingContext():
|
|
fetching_deferred.callback(missing_events)
|
|
|
|
if already_fetching_deferreds:
|
|
# Wait for the other event requests to finish and add their results
|
|
# to ours.
|
|
results = await make_deferred_yieldable(
|
|
defer.gatherResults(
|
|
(d.observe() for d in already_fetching_deferreds),
|
|
consumeErrors=True,
|
|
)
|
|
).addErrback(unwrapFirstError)
|
|
|
|
for result in results:
|
|
# We filter out events that we haven't asked for as we might get
|
|
# a *lot* of superfluous events back, and there is no point
|
|
# going through and inserting them all (which can take time).
|
|
event_entry_map.update(
|
|
(event_id, entry)
|
|
for event_id, entry in result.items()
|
|
if event_id in already_fetching_ids
|
|
)
|
|
|
|
if not allow_rejected:
|
|
event_entry_map = {
|
|
event_id: entry
|
|
for event_id, entry in event_entry_map.items()
|
|
if not entry.event.rejected_reason
|
|
}
|
|
|
|
return event_entry_map
|
|
|
|
def _invalidate_get_event_cache(self, event_id: str) -> None:
|
|
self._get_event_cache.invalidate((event_id,))
|
|
|
|
def _get_events_from_cache(
|
|
self, events: Iterable[str], update_metrics: bool = True
|
|
) -> Dict[str, EventCacheEntry]:
|
|
"""Fetch events from the caches.
|
|
|
|
May return rejected events.
|
|
|
|
Args:
|
|
events: list of event_ids to fetch
|
|
update_metrics: Whether to update the cache hit ratio metrics
|
|
"""
|
|
event_map = {}
|
|
|
|
for event_id in events:
|
|
ret = self._get_event_cache.get(
|
|
(event_id,), None, update_metrics=update_metrics
|
|
)
|
|
if not ret:
|
|
continue
|
|
|
|
event_map[event_id] = ret
|
|
|
|
return event_map
|
|
|
|
async def get_stripped_room_state_from_event_context(
|
|
self,
|
|
context: EventContext,
|
|
state_types_to_include: Container[str],
|
|
membership_user_id: Optional[str] = None,
|
|
) -> List[JsonDict]:
|
|
"""
|
|
Retrieve the stripped state from a room, given an event context to retrieve state
|
|
from as well as the state types to include. Optionally, include the membership
|
|
events from a specific user.
|
|
|
|
"Stripped" state means that only the `type`, `state_key`, `content` and `sender` keys
|
|
are included from each state event.
|
|
|
|
Args:
|
|
context: The event context to retrieve state of the room from.
|
|
state_types_to_include: The type of state events to include.
|
|
membership_user_id: An optional user ID to include the stripped membership state
|
|
events of. This is useful when generating the stripped state of a room for
|
|
invites. We want to send membership events of the inviter, so that the
|
|
invitee can display the inviter's profile information if the room lacks any.
|
|
|
|
Returns:
|
|
A list of dictionaries, each representing a stripped state event from the room.
|
|
"""
|
|
current_state_ids = await context.get_current_state_ids()
|
|
|
|
# We know this event is not an outlier, so this must be
|
|
# non-None.
|
|
assert current_state_ids is not None
|
|
|
|
# The state to include
|
|
state_to_include_ids = [
|
|
e_id
|
|
for k, e_id in current_state_ids.items()
|
|
if k[0] in state_types_to_include
|
|
or (membership_user_id and k == (EventTypes.Member, membership_user_id))
|
|
]
|
|
|
|
state_to_include = await self.get_events(state_to_include_ids)
|
|
|
|
return [
|
|
{
|
|
"type": e.type,
|
|
"state_key": e.state_key,
|
|
"content": e.content,
|
|
"sender": e.sender,
|
|
}
|
|
for e in state_to_include.values()
|
|
]
|
|
|
|
def _maybe_start_fetch_thread(self) -> None:
|
|
"""Starts an event fetch thread if we are not yet at the maximum number."""
|
|
with self._event_fetch_lock:
|
|
if (
|
|
self._event_fetch_list
|
|
and self._event_fetch_ongoing < EVENT_QUEUE_THREADS
|
|
):
|
|
self._event_fetch_ongoing += 1
|
|
event_fetch_ongoing_gauge.set(self._event_fetch_ongoing)
|
|
# `_event_fetch_ongoing` is decremented in `_fetch_thread`.
|
|
should_start = True
|
|
else:
|
|
should_start = False
|
|
|
|
if should_start:
|
|
run_as_background_process("fetch_events", self._fetch_thread)
|
|
|
|
async def _fetch_thread(self) -> None:
|
|
"""Services requests for events from `_event_fetch_list`."""
|
|
exc = None
|
|
try:
|
|
await self.db_pool.runWithConnection(self._fetch_loop)
|
|
except BaseException as e:
|
|
exc = e
|
|
raise
|
|
finally:
|
|
should_restart = False
|
|
event_fetches_to_fail = []
|
|
with self._event_fetch_lock:
|
|
self._event_fetch_ongoing -= 1
|
|
event_fetch_ongoing_gauge.set(self._event_fetch_ongoing)
|
|
|
|
# There may still be work remaining in `_event_fetch_list` if we
|
|
# failed, or it was added in between us deciding to exit and
|
|
# decrementing `_event_fetch_ongoing`.
|
|
if self._event_fetch_list:
|
|
if exc is None:
|
|
# We decided to exit, but then some more work was added
|
|
# before `_event_fetch_ongoing` was decremented.
|
|
# If a new event fetch thread was not started, we should
|
|
# restart ourselves since the remaining event fetch threads
|
|
# may take a while to get around to the new work.
|
|
#
|
|
# Unfortunately it is not possible to tell whether a new
|
|
# event fetch thread was started, so we restart
|
|
# unconditionally. If we are unlucky, we will end up with
|
|
# an idle fetch thread, but it will time out after
|
|
# `EVENT_QUEUE_ITERATIONS * EVENT_QUEUE_TIMEOUT_S` seconds
|
|
# in any case.
|
|
#
|
|
# Note that multiple fetch threads may run down this path at
|
|
# the same time.
|
|
should_restart = True
|
|
elif isinstance(exc, Exception):
|
|
if self._event_fetch_ongoing == 0:
|
|
# We were the last remaining fetcher and failed.
|
|
# Fail any outstanding fetches since no one else will
|
|
# handle them.
|
|
event_fetches_to_fail = self._event_fetch_list
|
|
self._event_fetch_list = []
|
|
else:
|
|
# We weren't the last remaining fetcher, so another
|
|
# fetcher will pick up the work. This will either happen
|
|
# after their existing work, however long that takes,
|
|
# or after at most `EVENT_QUEUE_TIMEOUT_S` seconds if
|
|
# they are idle.
|
|
pass
|
|
else:
|
|
# The exception is a `SystemExit`, `KeyboardInterrupt` or
|
|
# `GeneratorExit`. Don't try to do anything clever here.
|
|
pass
|
|
|
|
if should_restart:
|
|
# We exited cleanly but noticed more work.
|
|
self._maybe_start_fetch_thread()
|
|
|
|
if event_fetches_to_fail:
|
|
# We were the last remaining fetcher and failed.
|
|
# Fail any outstanding fetches since no one else will handle them.
|
|
assert exc is not None
|
|
with PreserveLoggingContext():
|
|
for _, deferred in event_fetches_to_fail:
|
|
deferred.errback(exc)
|
|
|
|
def _fetch_loop(self, conn: LoggingDatabaseConnection) -> None:
|
|
"""Takes a database connection and waits for requests for events from
|
|
the _event_fetch_list queue.
|
|
"""
|
|
i = 0
|
|
while True:
|
|
with self._event_fetch_lock:
|
|
event_list = self._event_fetch_list
|
|
self._event_fetch_list = []
|
|
|
|
if not event_list:
|
|
# There are no requests waiting. If we haven't yet reached the
|
|
# maximum iteration limit, wait for some more requests to turn up.
|
|
# Otherwise, bail out.
|
|
single_threaded = self.database_engine.single_threaded
|
|
if (
|
|
not self.USE_DEDICATED_DB_THREADS_FOR_EVENT_FETCHING
|
|
or single_threaded
|
|
or i > EVENT_QUEUE_ITERATIONS
|
|
):
|
|
return
|
|
|
|
self._event_fetch_lock.wait(EVENT_QUEUE_TIMEOUT_S)
|
|
i += 1
|
|
continue
|
|
i = 0
|
|
|
|
self._fetch_event_list(conn, event_list)
|
|
|
|
def _fetch_event_list(
|
|
self,
|
|
conn: LoggingDatabaseConnection,
|
|
event_list: List[Tuple[Iterable[str], "defer.Deferred[Dict[str, _EventRow]]"]],
|
|
) -> None:
|
|
"""Handle a load of requests from the _event_fetch_list queue
|
|
|
|
Args:
|
|
conn: database connection
|
|
|
|
event_list:
|
|
The fetch requests. Each entry consists of a list of event
|
|
ids to be fetched, and a deferred to be completed once the
|
|
events have been fetched.
|
|
|
|
The deferreds are callbacked with a dictionary mapping from event id
|
|
to event row. Note that it may well contain additional events that
|
|
were not part of this request.
|
|
"""
|
|
with Measure(self._clock, "_fetch_event_list"):
|
|
try:
|
|
events_to_fetch = {
|
|
event_id for events, _ in event_list for event_id in events
|
|
}
|
|
|
|
row_dict = self.db_pool.new_transaction(
|
|
conn, "do_fetch", [], [], self._fetch_event_rows, events_to_fetch
|
|
)
|
|
|
|
# We only want to resolve deferreds from the main thread
|
|
def fire() -> None:
|
|
for _, d in event_list:
|
|
d.callback(row_dict)
|
|
|
|
with PreserveLoggingContext():
|
|
self.hs.get_reactor().callFromThread(fire)
|
|
except Exception as e:
|
|
logger.exception("do_fetch")
|
|
|
|
# We only want to resolve deferreds from the main thread
|
|
def fire_errback(exc: Exception) -> None:
|
|
for _, d in event_list:
|
|
d.errback(exc)
|
|
|
|
with PreserveLoggingContext():
|
|
self.hs.get_reactor().callFromThread(fire_errback, e)
|
|
|
|
async def _get_events_from_db(
|
|
self, event_ids: Collection[str]
|
|
) -> Dict[str, EventCacheEntry]:
|
|
"""Fetch a bunch of events from the database.
|
|
|
|
May return rejected events.
|
|
|
|
Returned events will be added to the cache for future lookups.
|
|
|
|
Unknown events are omitted from the response.
|
|
|
|
Args:
|
|
event_ids: The event_ids of the events to fetch
|
|
|
|
Returns:
|
|
map from event id to result. May return extra events which
|
|
weren't asked for.
|
|
"""
|
|
fetched_event_ids: Set[str] = set()
|
|
fetched_events: Dict[str, _EventRow] = {}
|
|
events_to_fetch = event_ids
|
|
|
|
while events_to_fetch:
|
|
row_map = await self._enqueue_events(events_to_fetch)
|
|
|
|
# we need to recursively fetch any redactions of those events
|
|
redaction_ids: Set[str] = set()
|
|
for event_id in events_to_fetch:
|
|
row = row_map.get(event_id)
|
|
fetched_event_ids.add(event_id)
|
|
if row:
|
|
fetched_events[event_id] = row
|
|
redaction_ids.update(row.redactions)
|
|
|
|
events_to_fetch = redaction_ids.difference(fetched_event_ids)
|
|
if events_to_fetch:
|
|
logger.debug("Also fetching redaction events %s", events_to_fetch)
|
|
|
|
# build a map from event_id to EventBase
|
|
event_map: Dict[str, EventBase] = {}
|
|
for event_id, row in fetched_events.items():
|
|
assert row.event_id == event_id
|
|
|
|
rejected_reason = row.rejected_reason
|
|
|
|
# If the event or metadata cannot be parsed, log the error and act
|
|
# as if the event is unknown.
|
|
try:
|
|
d = db_to_json(row.json)
|
|
except ValueError:
|
|
logger.error("Unable to parse json from event: %s", event_id)
|
|
continue
|
|
try:
|
|
internal_metadata = db_to_json(row.internal_metadata)
|
|
except ValueError:
|
|
logger.error(
|
|
"Unable to parse internal_metadata from event: %s", event_id
|
|
)
|
|
continue
|
|
|
|
format_version = row.format_version
|
|
if format_version is None:
|
|
# This means that we stored the event before we had the concept
|
|
# of a event format version, so it must be a V1 event.
|
|
format_version = EventFormatVersions.V1
|
|
|
|
room_version_id = row.room_version_id
|
|
|
|
room_version: Optional[RoomVersion]
|
|
if not room_version_id:
|
|
# this should only happen for out-of-band membership events which
|
|
# arrived before #6983 landed. For all other events, we should have
|
|
# an entry in the 'rooms' table.
|
|
#
|
|
# However, the 'out_of_band_membership' flag is unreliable for older
|
|
# invites, so just accept it for all membership events.
|
|
#
|
|
if d["type"] != EventTypes.Member:
|
|
raise Exception(
|
|
"Room %s for event %s is unknown" % (d["room_id"], event_id)
|
|
)
|
|
|
|
# so, assuming this is an out-of-band-invite that arrived before #6983
|
|
# landed, we know that the room version must be v5 or earlier (because
|
|
# v6 hadn't been invented at that point, so invites from such rooms
|
|
# would have been rejected.)
|
|
#
|
|
# The main reason we need to know the room version here (other than
|
|
# choosing the right python Event class) is in case the event later has
|
|
# to be redacted - and all the room versions up to v5 used the same
|
|
# redaction algorithm.
|
|
#
|
|
# So, the following approximations should be adequate.
|
|
|
|
if format_version == EventFormatVersions.V1:
|
|
# if it's event format v1 then it must be room v1 or v2
|
|
room_version = RoomVersions.V1
|
|
elif format_version == EventFormatVersions.V2:
|
|
# if it's event format v2 then it must be room v3
|
|
room_version = RoomVersions.V3
|
|
else:
|
|
# if it's event format v3 then it must be room v4 or v5
|
|
room_version = RoomVersions.V5
|
|
else:
|
|
room_version = KNOWN_ROOM_VERSIONS.get(room_version_id)
|
|
if not room_version:
|
|
logger.warning(
|
|
"Event %s in room %s has unknown room version %s",
|
|
event_id,
|
|
d["room_id"],
|
|
room_version_id,
|
|
)
|
|
continue
|
|
|
|
if room_version.event_format != format_version:
|
|
logger.error(
|
|
"Event %s in room %s with version %s has wrong format: "
|
|
"expected %s, was %s",
|
|
event_id,
|
|
d["room_id"],
|
|
room_version_id,
|
|
room_version.event_format,
|
|
format_version,
|
|
)
|
|
continue
|
|
|
|
original_ev = make_event_from_dict(
|
|
event_dict=d,
|
|
room_version=room_version,
|
|
internal_metadata_dict=internal_metadata,
|
|
rejected_reason=rejected_reason,
|
|
)
|
|
original_ev.internal_metadata.stream_ordering = row.stream_ordering
|
|
original_ev.internal_metadata.outlier = row.outlier
|
|
|
|
event_map[event_id] = original_ev
|
|
|
|
# finally, we can decide whether each one needs redacting, and build
|
|
# the cache entries.
|
|
result_map: Dict[str, EventCacheEntry] = {}
|
|
for event_id, original_ev in event_map.items():
|
|
redactions = fetched_events[event_id].redactions
|
|
redacted_event = self._maybe_redact_event_row(
|
|
original_ev, redactions, event_map
|
|
)
|
|
|
|
cache_entry = EventCacheEntry(
|
|
event=original_ev, redacted_event=redacted_event
|
|
)
|
|
|
|
self._get_event_cache.set((event_id,), cache_entry)
|
|
result_map[event_id] = cache_entry
|
|
|
|
return result_map
|
|
|
|
async def _enqueue_events(self, events: Collection[str]) -> Dict[str, _EventRow]:
|
|
"""Fetches events from the database using the _event_fetch_list. This
|
|
allows batch and bulk fetching of events - it allows us to fetch events
|
|
without having to create a new transaction for each request for events.
|
|
|
|
Args:
|
|
events: events to be fetched.
|
|
|
|
Returns:
|
|
A map from event id to row data from the database. May contain events
|
|
that weren't requested.
|
|
"""
|
|
|
|
events_d: "defer.Deferred[Dict[str, _EventRow]]" = defer.Deferred()
|
|
with self._event_fetch_lock:
|
|
self._event_fetch_list.append((events, events_d))
|
|
self._event_fetch_lock.notify()
|
|
|
|
self._maybe_start_fetch_thread()
|
|
|
|
logger.debug("Loading %d events: %s", len(events), events)
|
|
with PreserveLoggingContext():
|
|
row_map = await events_d
|
|
logger.debug("Loaded %d events (%d rows)", len(events), len(row_map))
|
|
|
|
return row_map
|
|
|
|
def _fetch_event_rows(
|
|
self, txn: LoggingTransaction, event_ids: Iterable[str]
|
|
) -> Dict[str, _EventRow]:
|
|
"""Fetch event rows from the database
|
|
|
|
Events which are not found are omitted from the result.
|
|
|
|
Args:
|
|
txn: The database transaction.
|
|
event_ids: event IDs to fetch
|
|
|
|
Returns:
|
|
A map from event id to event info.
|
|
"""
|
|
event_dict = {}
|
|
for evs in batch_iter(event_ids, 200):
|
|
sql = """\
|
|
SELECT
|
|
e.event_id,
|
|
e.stream_ordering,
|
|
ej.internal_metadata,
|
|
ej.json,
|
|
ej.format_version,
|
|
r.room_version,
|
|
rej.reason,
|
|
e.outlier
|
|
FROM events AS e
|
|
JOIN event_json AS ej USING (event_id)
|
|
LEFT JOIN rooms r ON r.room_id = e.room_id
|
|
LEFT JOIN rejections as rej USING (event_id)
|
|
WHERE """
|
|
|
|
clause, args = make_in_list_sql_clause(
|
|
txn.database_engine, "e.event_id", evs
|
|
)
|
|
|
|
txn.execute(sql + clause, args)
|
|
|
|
for row in txn:
|
|
event_id = row[0]
|
|
event_dict[event_id] = _EventRow(
|
|
event_id=event_id,
|
|
stream_ordering=row[1],
|
|
internal_metadata=row[2],
|
|
json=row[3],
|
|
format_version=row[4],
|
|
room_version_id=row[5],
|
|
rejected_reason=row[6],
|
|
redactions=[],
|
|
outlier=row[7],
|
|
)
|
|
|
|
# check for redactions
|
|
redactions_sql = "SELECT event_id, redacts FROM redactions WHERE "
|
|
|
|
clause, args = make_in_list_sql_clause(txn.database_engine, "redacts", evs)
|
|
|
|
txn.execute(redactions_sql + clause, args)
|
|
|
|
for (redacter, redacted) in txn:
|
|
d = event_dict.get(redacted)
|
|
if d:
|
|
d.redactions.append(redacter)
|
|
|
|
return event_dict
|
|
|
|
def _maybe_redact_event_row(
|
|
self,
|
|
original_ev: EventBase,
|
|
redactions: Iterable[str],
|
|
event_map: Dict[str, EventBase],
|
|
) -> Optional[EventBase]:
|
|
"""Given an event object and a list of possible redacting event ids,
|
|
determine whether to honour any of those redactions and if so return a redacted
|
|
event.
|
|
|
|
Args:
|
|
original_ev: The original event.
|
|
redactions: list of event ids of potential redaction events
|
|
event_map: other events which have been fetched, in which we can
|
|
look up the redaaction events. Map from event id to event.
|
|
|
|
Returns:
|
|
If the event should be redacted, a pruned event object. Otherwise, None.
|
|
"""
|
|
if original_ev.type == "m.room.create":
|
|
# we choose to ignore redactions of m.room.create events.
|
|
return None
|
|
|
|
for redaction_id in redactions:
|
|
redaction_event = event_map.get(redaction_id)
|
|
if not redaction_event or redaction_event.rejected_reason:
|
|
# we don't have the redaction event, or the redaction event was not
|
|
# authorized.
|
|
logger.debug(
|
|
"%s was redacted by %s but redaction not found/authed",
|
|
original_ev.event_id,
|
|
redaction_id,
|
|
)
|
|
continue
|
|
|
|
if redaction_event.room_id != original_ev.room_id:
|
|
logger.debug(
|
|
"%s was redacted by %s but redaction was in a different room!",
|
|
original_ev.event_id,
|
|
redaction_id,
|
|
)
|
|
continue
|
|
|
|
# Starting in room version v3, some redactions need to be
|
|
# rechecked if we didn't have the redacted event at the
|
|
# time, so we recheck on read instead.
|
|
if redaction_event.internal_metadata.need_to_check_redaction():
|
|
expected_domain = get_domain_from_id(original_ev.sender)
|
|
if get_domain_from_id(redaction_event.sender) == expected_domain:
|
|
# This redaction event is allowed. Mark as not needing a recheck.
|
|
redaction_event.internal_metadata.recheck_redaction = False
|
|
else:
|
|
# Senders don't match, so the event isn't actually redacted
|
|
logger.debug(
|
|
"%s was redacted by %s but the senders don't match",
|
|
original_ev.event_id,
|
|
redaction_id,
|
|
)
|
|
continue
|
|
|
|
logger.debug("Redacting %s due to %s", original_ev.event_id, redaction_id)
|
|
|
|
# we found a good redaction event. Redact!
|
|
redacted_event = prune_event(original_ev)
|
|
redacted_event.unsigned["redacted_by"] = redaction_id
|
|
|
|
# It's fine to add the event directly, since get_pdu_json
|
|
# will serialise this field correctly
|
|
redacted_event.unsigned["redacted_because"] = redaction_event
|
|
|
|
return redacted_event
|
|
|
|
# no valid redaction found for this event
|
|
return None
|
|
|
|
async def have_events_in_timeline(self, event_ids: Iterable[str]) -> Set[str]:
|
|
"""Given a list of event ids, check if we have already processed and
|
|
stored them as non outliers.
|
|
"""
|
|
rows = await self.db_pool.simple_select_many_batch(
|
|
table="events",
|
|
retcols=("event_id",),
|
|
column="event_id",
|
|
iterable=list(event_ids),
|
|
keyvalues={"outlier": False},
|
|
desc="have_events_in_timeline",
|
|
)
|
|
|
|
return {r["event_id"] for r in rows}
|
|
|
|
async def have_seen_events(
|
|
self, room_id: str, event_ids: Iterable[str]
|
|
) -> Set[str]:
|
|
"""Given a list of event ids, check if we have already processed them.
|
|
|
|
The room_id is only used to structure the cache (so that it can later be
|
|
invalidated by room_id) - there is no guarantee that the events are actually
|
|
in the room in question.
|
|
|
|
Args:
|
|
room_id: Room we are polling
|
|
event_ids: events we are looking for
|
|
|
|
Returns:
|
|
The set of events we have already seen.
|
|
"""
|
|
res = await self._have_seen_events_dict(
|
|
(room_id, event_id) for event_id in event_ids
|
|
)
|
|
return {eid for ((_rid, eid), have_event) in res.items() if have_event}
|
|
|
|
@cachedList("have_seen_event", "keys")
|
|
async def _have_seen_events_dict(
|
|
self, keys: Iterable[Tuple[str, str]]
|
|
) -> Dict[Tuple[str, str], bool]:
|
|
"""Helper for have_seen_events
|
|
|
|
Returns:
|
|
a dict {(room_id, event_id)-> bool}
|
|
"""
|
|
# if the event cache contains the event, obviously we've seen it.
|
|
|
|
cache_results = {
|
|
(rid, eid) for (rid, eid) in keys if self._get_event_cache.contains((eid,))
|
|
}
|
|
results = {x: True for x in cache_results}
|
|
|
|
def have_seen_events_txn(
|
|
txn: LoggingTransaction, chunk: Tuple[Tuple[str, str], ...]
|
|
) -> None:
|
|
# we deliberately do *not* query the database for room_id, to make the
|
|
# query an index-only lookup on `events_event_id_key`.
|
|
#
|
|
# We therefore pull the events from the database into a set...
|
|
|
|
sql = "SELECT event_id FROM events AS e WHERE "
|
|
clause, args = make_in_list_sql_clause(
|
|
txn.database_engine, "e.event_id", [eid for (_rid, eid) in chunk]
|
|
)
|
|
txn.execute(sql + clause, args)
|
|
found_events = {eid for eid, in txn}
|
|
|
|
# ... and then we can update the results for each row in the batch
|
|
results.update({(rid, eid): (eid in found_events) for (rid, eid) in chunk})
|
|
|
|
# each batch requires its own index scan, so we make the batches as big as
|
|
# possible.
|
|
for chunk in batch_iter((k for k in keys if k not in cache_results), 500):
|
|
await self.db_pool.runInteraction(
|
|
"have_seen_events", have_seen_events_txn, chunk
|
|
)
|
|
|
|
return results
|
|
|
|
@cached(max_entries=100000, tree=True)
|
|
async def have_seen_event(self, room_id: str, event_id: str) -> NoReturn:
|
|
# this only exists for the benefit of the @cachedList descriptor on
|
|
# _have_seen_events_dict
|
|
raise NotImplementedError()
|
|
|
|
def _get_current_state_event_counts_txn(
|
|
self, txn: LoggingTransaction, room_id: str
|
|
) -> int:
|
|
"""
|
|
See get_current_state_event_counts.
|
|
"""
|
|
sql = "SELECT COUNT(*) FROM current_state_events WHERE room_id=?"
|
|
txn.execute(sql, (room_id,))
|
|
row = txn.fetchone()
|
|
return row[0] if row else 0
|
|
|
|
async def get_current_state_event_counts(self, room_id: str) -> int:
|
|
"""
|
|
Gets the current number of state events in a room.
|
|
|
|
Args:
|
|
room_id: The room ID to query.
|
|
|
|
Returns:
|
|
The current number of state events.
|
|
"""
|
|
return await self.db_pool.runInteraction(
|
|
"get_current_state_event_counts",
|
|
self._get_current_state_event_counts_txn,
|
|
room_id,
|
|
)
|
|
|
|
async def get_room_complexity(self, room_id: str) -> Dict[str, float]:
|
|
"""
|
|
Get a rough approximation of the complexity of the room. This is used by
|
|
remote servers to decide whether they wish to join the room or not.
|
|
Higher complexity value indicates that being in the room will consume
|
|
more resources.
|
|
|
|
Args:
|
|
room_id: The room ID to query.
|
|
|
|
Returns:
|
|
dict[str:float] of complexity version to complexity.
|
|
"""
|
|
state_events = await self.get_current_state_event_counts(room_id)
|
|
|
|
# Call this one "v1", so we can introduce new ones as we want to develop
|
|
# it.
|
|
complexity_v1 = round(state_events / 500, 2)
|
|
|
|
return {"v1": complexity_v1}
|
|
|
|
async def get_all_new_forward_event_rows(
|
|
self, instance_name: str, last_id: int, current_id: int, limit: int
|
|
) -> List[Tuple[int, str, str, str, str, str, str, str, str]]:
|
|
"""Returns new events, for the Events replication stream
|
|
|
|
Args:
|
|
last_id: the last stream_id from the previous batch.
|
|
current_id: the maximum stream_id to return up to
|
|
limit: the maximum number of rows to return
|
|
|
|
Returns:
|
|
a list of events stream rows. Each tuple consists of a stream id as
|
|
the first element, followed by fields suitable for casting into an
|
|
EventsStreamRow.
|
|
"""
|
|
|
|
def get_all_new_forward_event_rows(
|
|
txn: LoggingTransaction,
|
|
) -> List[Tuple[int, str, str, str, str, str, str, str, str]]:
|
|
sql = (
|
|
"SELECT e.stream_ordering, e.event_id, e.room_id, e.type,"
|
|
" se.state_key, redacts, relates_to_id, membership, rejections.reason IS NOT NULL"
|
|
" FROM events AS e"
|
|
" LEFT JOIN redactions USING (event_id)"
|
|
" LEFT JOIN state_events AS se USING (event_id)"
|
|
" LEFT JOIN event_relations USING (event_id)"
|
|
" LEFT JOIN room_memberships USING (event_id)"
|
|
" LEFT JOIN rejections USING (event_id)"
|
|
" WHERE ? < stream_ordering AND stream_ordering <= ?"
|
|
" AND instance_name = ?"
|
|
" ORDER BY stream_ordering ASC"
|
|
" LIMIT ?"
|
|
)
|
|
txn.execute(sql, (last_id, current_id, instance_name, limit))
|
|
return cast(
|
|
List[Tuple[int, str, str, str, str, str, str, str, str]], txn.fetchall()
|
|
)
|
|
|
|
return await self.db_pool.runInteraction(
|
|
"get_all_new_forward_event_rows", get_all_new_forward_event_rows
|
|
)
|
|
|
|
async def get_ex_outlier_stream_rows(
|
|
self, instance_name: str, last_id: int, current_id: int
|
|
) -> List[Tuple[int, str, str, str, str, str, str, str, str]]:
|
|
"""Returns de-outliered events, for the Events replication stream
|
|
|
|
Args:
|
|
last_id: the last stream_id from the previous batch.
|
|
current_id: the maximum stream_id to return up to
|
|
|
|
Returns:
|
|
a list of events stream rows. Each tuple consists of a stream id as
|
|
the first element, followed by fields suitable for casting into an
|
|
EventsStreamRow.
|
|
"""
|
|
|
|
def get_ex_outlier_stream_rows_txn(
|
|
txn: LoggingTransaction,
|
|
) -> List[Tuple[int, str, str, str, str, str, str, str, str]]:
|
|
sql = (
|
|
"SELECT event_stream_ordering, e.event_id, e.room_id, e.type,"
|
|
" se.state_key, redacts, relates_to_id, membership, rejections.reason IS NOT NULL"
|
|
" FROM events AS e"
|
|
" INNER JOIN ex_outlier_stream AS out USING (event_id)"
|
|
" LEFT JOIN redactions USING (event_id)"
|
|
" LEFT JOIN state_events AS se USING (event_id)"
|
|
" LEFT JOIN event_relations USING (event_id)"
|
|
" LEFT JOIN room_memberships USING (event_id)"
|
|
" LEFT JOIN rejections USING (event_id)"
|
|
" WHERE ? < event_stream_ordering"
|
|
" AND event_stream_ordering <= ?"
|
|
" AND out.instance_name = ?"
|
|
" ORDER BY event_stream_ordering ASC"
|
|
)
|
|
|
|
txn.execute(sql, (last_id, current_id, instance_name))
|
|
return cast(
|
|
List[Tuple[int, str, str, str, str, str, str, str, str]], txn.fetchall()
|
|
)
|
|
|
|
return await self.db_pool.runInteraction(
|
|
"get_ex_outlier_stream_rows", get_ex_outlier_stream_rows_txn
|
|
)
|
|
|
|
async def get_all_new_backfill_event_rows(
|
|
self, instance_name: str, last_id: int, current_id: int, limit: int
|
|
) -> Tuple[List[Tuple[int, Tuple[str, str, str, str, str, str]]], int, bool]:
|
|
"""Get updates for backfill replication stream, including all new
|
|
backfilled events and events that have gone from being outliers to not.
|
|
|
|
NOTE: The IDs given here are from replication, and so should be
|
|
*positive*.
|
|
|
|
Args:
|
|
instance_name: The writer we want to fetch updates from. Unused
|
|
here since there is only ever one writer.
|
|
last_id: The token to fetch updates from. Exclusive.
|
|
current_id: The token to fetch updates up to. Inclusive.
|
|
limit: The requested limit for the number of rows to return. The
|
|
function may return more or fewer rows.
|
|
|
|
Returns:
|
|
A tuple consisting of: the updates, a token to use to fetch
|
|
subsequent updates, and whether we returned fewer rows than exists
|
|
between the requested tokens due to the limit.
|
|
|
|
The token returned can be used in a subsequent call to this
|
|
function to get further updatees.
|
|
|
|
The updates are a list of 2-tuples of stream ID and the row data
|
|
"""
|
|
if last_id == current_id:
|
|
return [], current_id, False
|
|
|
|
def get_all_new_backfill_event_rows(
|
|
txn: LoggingTransaction,
|
|
) -> Tuple[List[Tuple[int, Tuple[str, str, str, str, str, str]]], int, bool]:
|
|
sql = (
|
|
"SELECT -e.stream_ordering, e.event_id, e.room_id, e.type,"
|
|
" se.state_key, redacts, relates_to_id"
|
|
" FROM events AS e"
|
|
" LEFT JOIN redactions USING (event_id)"
|
|
" LEFT JOIN state_events AS se USING (event_id)"
|
|
" LEFT JOIN event_relations USING (event_id)"
|
|
" WHERE ? > stream_ordering AND stream_ordering >= ?"
|
|
" AND instance_name = ?"
|
|
" ORDER BY stream_ordering ASC"
|
|
" LIMIT ?"
|
|
)
|
|
txn.execute(sql, (-last_id, -current_id, instance_name, limit))
|
|
new_event_updates: List[
|
|
Tuple[int, Tuple[str, str, str, str, str, str]]
|
|
] = []
|
|
row: Tuple[int, str, str, str, str, str, str]
|
|
# Type safety: iterating over `txn` yields `Tuple`, i.e.
|
|
# `Tuple[Any, ...]` of arbitrary length. Mypy detects assigning a
|
|
# variadic tuple to a fixed length tuple and flags it up as an error.
|
|
for row in txn: # type: ignore[assignment]
|
|
new_event_updates.append((row[0], row[1:]))
|
|
|
|
limited = False
|
|
if len(new_event_updates) == limit:
|
|
upper_bound = new_event_updates[-1][0]
|
|
limited = True
|
|
else:
|
|
upper_bound = current_id
|
|
|
|
sql = (
|
|
"SELECT -event_stream_ordering, e.event_id, e.room_id, e.type,"
|
|
" se.state_key, redacts, relates_to_id"
|
|
" FROM events AS e"
|
|
" INNER JOIN ex_outlier_stream AS out USING (event_id)"
|
|
" LEFT JOIN redactions USING (event_id)"
|
|
" LEFT JOIN state_events AS se USING (event_id)"
|
|
" LEFT JOIN event_relations USING (event_id)"
|
|
" WHERE ? > event_stream_ordering"
|
|
" AND event_stream_ordering >= ?"
|
|
" AND out.instance_name = ?"
|
|
" ORDER BY event_stream_ordering DESC"
|
|
)
|
|
txn.execute(sql, (-last_id, -upper_bound, instance_name))
|
|
# Type safety: iterating over `txn` yields `Tuple`, i.e.
|
|
# `Tuple[Any, ...]` of arbitrary length. Mypy detects assigning a
|
|
# variadic tuple to a fixed length tuple and flags it up as an error.
|
|
for row in txn: # type: ignore[assignment]
|
|
new_event_updates.append((row[0], row[1:]))
|
|
|
|
if len(new_event_updates) >= limit:
|
|
upper_bound = new_event_updates[-1][0]
|
|
limited = True
|
|
|
|
return new_event_updates, upper_bound, limited
|
|
|
|
return await self.db_pool.runInteraction(
|
|
"get_all_new_backfill_event_rows", get_all_new_backfill_event_rows
|
|
)
|
|
|
|
async def get_all_updated_current_state_deltas(
|
|
self, instance_name: str, from_token: int, to_token: int, target_row_count: int
|
|
) -> Tuple[List[Tuple[int, str, str, str, str]], int, bool]:
|
|
"""Fetch updates from current_state_delta_stream
|
|
|
|
Args:
|
|
from_token: The previous stream token. Updates from this stream id will
|
|
be excluded.
|
|
|
|
to_token: The current stream token (ie the upper limit). Updates up to this
|
|
stream id will be included (modulo the 'limit' param)
|
|
|
|
target_row_count: The number of rows to try to return. If more rows are
|
|
available, we will set 'limited' in the result. In the event of a large
|
|
batch, we may return more rows than this.
|
|
Returns:
|
|
A triplet `(updates, new_last_token, limited)`, where:
|
|
* `updates` is a list of database tuples.
|
|
* `new_last_token` is the new position in stream.
|
|
* `limited` is whether there are more updates to fetch.
|
|
"""
|
|
|
|
def get_all_updated_current_state_deltas_txn(
|
|
txn: LoggingTransaction,
|
|
) -> List[Tuple[int, str, str, str, str]]:
|
|
sql = """
|
|
SELECT stream_id, room_id, type, state_key, event_id
|
|
FROM current_state_delta_stream
|
|
WHERE ? < stream_id AND stream_id <= ?
|
|
AND instance_name = ?
|
|
ORDER BY stream_id ASC LIMIT ?
|
|
"""
|
|
txn.execute(sql, (from_token, to_token, instance_name, target_row_count))
|
|
return cast(List[Tuple[int, str, str, str, str]], txn.fetchall())
|
|
|
|
def get_deltas_for_stream_id_txn(
|
|
txn: LoggingTransaction, stream_id: int
|
|
) -> List[Tuple[int, str, str, str, str]]:
|
|
sql = """
|
|
SELECT stream_id, room_id, type, state_key, event_id
|
|
FROM current_state_delta_stream
|
|
WHERE stream_id = ?
|
|
"""
|
|
txn.execute(sql, [stream_id])
|
|
return cast(List[Tuple[int, str, str, str, str]], txn.fetchall())
|
|
|
|
# we need to make sure that, for every stream id in the results, we get *all*
|
|
# the rows with that stream id.
|
|
|
|
rows: List[Tuple[int, str, str, str, str]] = await self.db_pool.runInteraction(
|
|
"get_all_updated_current_state_deltas",
|
|
get_all_updated_current_state_deltas_txn,
|
|
)
|
|
|
|
# if we've got fewer rows than the limit, we're good
|
|
if len(rows) < target_row_count:
|
|
return rows, to_token, False
|
|
|
|
# we hit the limit, so reduce the upper limit so that we exclude the stream id
|
|
# of the last row in the result.
|
|
assert rows[-1][0] <= to_token
|
|
to_token = rows[-1][0] - 1
|
|
|
|
# search backwards through the list for the point to truncate
|
|
for idx in range(len(rows) - 1, 0, -1):
|
|
if rows[idx - 1][0] <= to_token:
|
|
return rows[:idx], to_token, True
|
|
|
|
# bother. We didn't get a full set of changes for even a single
|
|
# stream id. let's run the query again, without a row limit, but for
|
|
# just one stream id.
|
|
to_token += 1
|
|
rows = await self.db_pool.runInteraction(
|
|
"get_deltas_for_stream_id", get_deltas_for_stream_id_txn, to_token
|
|
)
|
|
|
|
return rows, to_token, True
|
|
|
|
async def is_event_after(self, event_id1: str, event_id2: str) -> bool:
|
|
"""Returns True if event_id1 is after event_id2 in the stream"""
|
|
to_1, so_1 = await self.get_event_ordering(event_id1)
|
|
to_2, so_2 = await self.get_event_ordering(event_id2)
|
|
return (to_1, so_1) > (to_2, so_2)
|
|
|
|
@cached(max_entries=5000)
|
|
async def get_event_ordering(self, event_id: str) -> Tuple[int, int]:
|
|
res = await self.db_pool.simple_select_one(
|
|
table="events",
|
|
retcols=["topological_ordering", "stream_ordering"],
|
|
keyvalues={"event_id": event_id},
|
|
allow_none=True,
|
|
)
|
|
|
|
if not res:
|
|
raise SynapseError(404, "Could not find event %s" % (event_id,))
|
|
|
|
return int(res["topological_ordering"]), int(res["stream_ordering"])
|
|
|
|
async def get_next_event_to_expire(self) -> Optional[Tuple[str, int]]:
|
|
"""Retrieve the entry with the lowest expiry timestamp in the event_expiry
|
|
table, or None if there's no more event to expire.
|
|
|
|
Returns:
|
|
A tuple containing the event ID as its first element and an expiry timestamp
|
|
as its second one, if there's at least one row in the event_expiry table.
|
|
None otherwise.
|
|
"""
|
|
|
|
def get_next_event_to_expire_txn(
|
|
txn: LoggingTransaction,
|
|
) -> Optional[Tuple[str, int]]:
|
|
txn.execute(
|
|
"""
|
|
SELECT event_id, expiry_ts FROM event_expiry
|
|
ORDER BY expiry_ts ASC LIMIT 1
|
|
"""
|
|
)
|
|
|
|
return cast(Optional[Tuple[str, int]], txn.fetchone())
|
|
|
|
return await self.db_pool.runInteraction(
|
|
desc="get_next_event_to_expire", func=get_next_event_to_expire_txn
|
|
)
|
|
|
|
async def get_event_id_from_transaction_id(
|
|
self, room_id: str, user_id: str, token_id: int, txn_id: str
|
|
) -> Optional[str]:
|
|
"""Look up if we have already persisted an event for the transaction ID,
|
|
returning the event ID if so.
|
|
"""
|
|
return await self.db_pool.simple_select_one_onecol(
|
|
table="event_txn_id",
|
|
keyvalues={
|
|
"room_id": room_id,
|
|
"user_id": user_id,
|
|
"token_id": token_id,
|
|
"txn_id": txn_id,
|
|
},
|
|
retcol="event_id",
|
|
allow_none=True,
|
|
desc="get_event_id_from_transaction_id",
|
|
)
|
|
|
|
async def get_already_persisted_events(
|
|
self, events: Iterable[EventBase]
|
|
) -> Dict[str, str]:
|
|
"""Look up if we have already persisted an event for the transaction ID,
|
|
returning a mapping from event ID in the given list to the event ID of
|
|
an existing event.
|
|
|
|
Also checks if there are duplicates in the given events, if there are
|
|
will map duplicates to the *first* event.
|
|
"""
|
|
|
|
mapping = {}
|
|
txn_id_to_event: Dict[Tuple[str, int, str], str] = {}
|
|
|
|
for event in events:
|
|
token_id = getattr(event.internal_metadata, "token_id", None)
|
|
txn_id = getattr(event.internal_metadata, "txn_id", None)
|
|
|
|
if token_id and txn_id:
|
|
# Check if this is a duplicate of an event in the given events.
|
|
existing = txn_id_to_event.get((event.room_id, token_id, txn_id))
|
|
if existing:
|
|
mapping[event.event_id] = existing
|
|
continue
|
|
|
|
# Check if this is a duplicate of an event we've already
|
|
# persisted.
|
|
existing = await self.get_event_id_from_transaction_id(
|
|
event.room_id, event.sender, token_id, txn_id
|
|
)
|
|
if existing:
|
|
mapping[event.event_id] = existing
|
|
txn_id_to_event[(event.room_id, token_id, txn_id)] = existing
|
|
else:
|
|
txn_id_to_event[(event.room_id, token_id, txn_id)] = event.event_id
|
|
|
|
return mapping
|
|
|
|
@wrap_as_background_process("_cleanup_old_transaction_ids")
|
|
async def _cleanup_old_transaction_ids(self) -> None:
|
|
"""Cleans out transaction id mappings older than 24hrs."""
|
|
|
|
def _cleanup_old_transaction_ids_txn(txn: LoggingTransaction) -> None:
|
|
sql = """
|
|
DELETE FROM event_txn_id
|
|
WHERE inserted_ts < ?
|
|
"""
|
|
one_day_ago = self._clock.time_msec() - 24 * 60 * 60 * 1000
|
|
txn.execute(sql, (one_day_ago,))
|
|
|
|
return await self.db_pool.runInteraction(
|
|
"_cleanup_old_transaction_ids",
|
|
_cleanup_old_transaction_ids_txn,
|
|
)
|
|
|
|
async def is_event_next_to_backward_gap(self, event: EventBase) -> bool:
|
|
"""Check if the given event is next to a backward gap of missing events.
|
|
<latest messages> A(False)--->B(False)--->C(True)---> <gap, unknown events> <oldest messages>
|
|
|
|
Args:
|
|
room_id: room where the event lives
|
|
event_id: event to check
|
|
|
|
Returns:
|
|
Boolean indicating whether it's an extremity
|
|
"""
|
|
|
|
def is_event_next_to_backward_gap_txn(txn: LoggingTransaction) -> bool:
|
|
# If the event in question has any of its prev_events listed as a
|
|
# backward extremity, it's next to a gap.
|
|
#
|
|
# We can't just check the backward edges in `event_edges` because
|
|
# when we persist events, we will also record the prev_events as
|
|
# edges to the event in question regardless of whether we have those
|
|
# prev_events yet. We need to check whether those prev_events are
|
|
# backward extremities, also known as gaps, that need to be
|
|
# backfilled.
|
|
backward_extremity_query = """
|
|
SELECT 1 FROM event_backward_extremities
|
|
WHERE
|
|
room_id = ?
|
|
AND %s
|
|
LIMIT 1
|
|
"""
|
|
|
|
# If the event in question is a backward extremity or has any of its
|
|
# prev_events listed as a backward extremity, it's next to a
|
|
# backward gap.
|
|
clause, args = make_in_list_sql_clause(
|
|
self.database_engine,
|
|
"event_id",
|
|
[event.event_id] + list(event.prev_event_ids()),
|
|
)
|
|
|
|
txn.execute(backward_extremity_query % (clause,), [event.room_id] + args)
|
|
backward_extremities = txn.fetchall()
|
|
|
|
# We consider any backward extremity as a backward gap
|
|
if len(backward_extremities):
|
|
return True
|
|
|
|
return False
|
|
|
|
return await self.db_pool.runInteraction(
|
|
"is_event_next_to_backward_gap_txn",
|
|
is_event_next_to_backward_gap_txn,
|
|
)
|
|
|
|
async def is_event_next_to_forward_gap(self, event: EventBase) -> bool:
|
|
"""Check if the given event is next to a forward gap of missing events.
|
|
The gap in front of the latest events is not considered a gap.
|
|
<latest messages> A(False)--->B(False)--->C(False)---> <gap, unknown events> <oldest messages>
|
|
<latest messages> A(False)--->B(False)---> <gap, unknown events> --->D(True)--->E(False) <oldest messages>
|
|
|
|
Args:
|
|
room_id: room where the event lives
|
|
event_id: event to check
|
|
|
|
Returns:
|
|
Boolean indicating whether it's an extremity
|
|
"""
|
|
|
|
def is_event_next_to_gap_txn(txn: LoggingTransaction) -> bool:
|
|
# If the event in question is a forward extremity, we will just
|
|
# consider any potential forward gap as not a gap since it's one of
|
|
# the latest events in the room.
|
|
#
|
|
# `event_forward_extremities` does not include backfilled or outlier
|
|
# events so we can't rely on it to find forward gaps. We can only
|
|
# use it to determine whether a message is the latest in the room.
|
|
#
|
|
# We can't combine this query with the `forward_edge_query` below
|
|
# because if the event in question has no forward edges (isn't
|
|
# referenced by any other event's prev_events) but is in
|
|
# `event_forward_extremities`, we don't want to return 0 rows and
|
|
# say it's next to a gap.
|
|
forward_extremity_query = """
|
|
SELECT 1 FROM event_forward_extremities
|
|
WHERE
|
|
room_id = ?
|
|
AND event_id = ?
|
|
LIMIT 1
|
|
"""
|
|
|
|
# Check to see whether the event in question is already referenced
|
|
# by another event. If we don't see any edges, we're next to a
|
|
# forward gap.
|
|
forward_edge_query = """
|
|
SELECT 1 FROM event_edges
|
|
/* Check to make sure the event referencing our event in question is not rejected */
|
|
LEFT JOIN rejections ON event_edges.event_id == rejections.event_id
|
|
WHERE
|
|
event_edges.room_id = ?
|
|
AND event_edges.prev_event_id = ?
|
|
/* It's not a valid edge if the event referencing our event in
|
|
* question is rejected.
|
|
*/
|
|
AND rejections.event_id IS NULL
|
|
LIMIT 1
|
|
"""
|
|
|
|
# We consider any forward extremity as the latest in the room and
|
|
# not a forward gap.
|
|
#
|
|
# To expand, even though there is technically a gap at the front of
|
|
# the room where the forward extremities are, we consider those the
|
|
# latest messages in the room so asking other homeservers for more
|
|
# is useless. The new latest messages will just be federated as
|
|
# usual.
|
|
txn.execute(forward_extremity_query, (event.room_id, event.event_id))
|
|
forward_extremities = txn.fetchall()
|
|
if len(forward_extremities):
|
|
return False
|
|
|
|
# If there are no forward edges to the event in question (another
|
|
# event hasn't referenced this event in their prev_events), then we
|
|
# assume there is a forward gap in the history.
|
|
txn.execute(forward_edge_query, (event.room_id, event.event_id))
|
|
forward_edges = txn.fetchall()
|
|
if not len(forward_edges):
|
|
return True
|
|
|
|
return False
|
|
|
|
return await self.db_pool.runInteraction(
|
|
"is_event_next_to_gap_txn",
|
|
is_event_next_to_gap_txn,
|
|
)
|
|
|
|
async def get_event_id_for_timestamp(
|
|
self, room_id: str, timestamp: int, direction: str
|
|
) -> Optional[str]:
|
|
"""Find the closest event to the given timestamp in the given direction.
|
|
|
|
Args:
|
|
room_id: Room to fetch the event from
|
|
timestamp: The point in time (inclusive) we should navigate from in
|
|
the given direction to find the closest event.
|
|
direction: ["f"|"b"] to indicate whether we should navigate forward
|
|
or backward from the given timestamp to find the closest event.
|
|
|
|
Returns:
|
|
The closest event_id otherwise None if we can't find any event in
|
|
the given direction.
|
|
"""
|
|
|
|
sql_template = """
|
|
SELECT event_id FROM events
|
|
LEFT JOIN rejections USING (event_id)
|
|
WHERE
|
|
origin_server_ts %s ?
|
|
AND room_id = ?
|
|
/* Make sure event is not rejected */
|
|
AND rejections.event_id IS NULL
|
|
ORDER BY origin_server_ts %s
|
|
LIMIT 1;
|
|
"""
|
|
|
|
def get_event_id_for_timestamp_txn(txn: LoggingTransaction) -> Optional[str]:
|
|
if direction == "b":
|
|
# Find closest event *before* a given timestamp. We use descending
|
|
# (which gives values largest to smallest) because we want the
|
|
# largest possible timestamp *before* the given timestamp.
|
|
comparison_operator = "<="
|
|
order = "DESC"
|
|
else:
|
|
# Find closest event *after* a given timestamp. We use ascending
|
|
# (which gives values smallest to largest) because we want the
|
|
# closest possible timestamp *after* the given timestamp.
|
|
comparison_operator = ">="
|
|
order = "ASC"
|
|
|
|
txn.execute(
|
|
sql_template % (comparison_operator, order), (timestamp, room_id)
|
|
)
|
|
row = txn.fetchone()
|
|
if row:
|
|
(event_id,) = row
|
|
return event_id
|
|
|
|
return None
|
|
|
|
if direction not in ("f", "b"):
|
|
raise ValueError("Unknown direction: %s" % (direction,))
|
|
|
|
return await self.db_pool.runInteraction(
|
|
"get_event_id_for_timestamp_txn",
|
|
get_event_id_for_timestamp_txn,
|
|
)
|