730 lines
26 KiB
Python
730 lines
26 KiB
Python
# -*- coding: utf-8 -*-
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# Copyright 2015, 2016 OpenMarket 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 re
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from collections import namedtuple
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from six import string_types
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from canonicaljson import json
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from twisted.internet import defer
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from synapse.api.errors import SynapseError
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from synapse.storage.engines import PostgresEngine, Sqlite3Engine
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from .background_updates import BackgroundUpdateStore
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logger = logging.getLogger(__name__)
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SearchEntry = namedtuple(
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'SearchEntry',
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['key', 'value', 'event_id', 'room_id', 'stream_ordering', 'origin_server_ts'],
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)
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class SearchStore(BackgroundUpdateStore):
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EVENT_SEARCH_UPDATE_NAME = "event_search"
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EVENT_SEARCH_ORDER_UPDATE_NAME = "event_search_order"
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EVENT_SEARCH_USE_GIST_POSTGRES_NAME = "event_search_postgres_gist"
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EVENT_SEARCH_USE_GIN_POSTGRES_NAME = "event_search_postgres_gin"
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def __init__(self, db_conn, hs):
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super(SearchStore, self).__init__(db_conn, hs)
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if not hs.config.enable_search:
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return
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self.register_background_update_handler(
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self.EVENT_SEARCH_UPDATE_NAME, self._background_reindex_search
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)
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self.register_background_update_handler(
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self.EVENT_SEARCH_ORDER_UPDATE_NAME, self._background_reindex_search_order
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)
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# we used to have a background update to turn the GIN index into a
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# GIST one; we no longer do that (obviously) because we actually want
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# a GIN index. However, it's possible that some people might still have
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# the background update queued, so we register a handler to clear the
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# background update.
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self.register_noop_background_update(self.EVENT_SEARCH_USE_GIST_POSTGRES_NAME)
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self.register_background_update_handler(
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self.EVENT_SEARCH_USE_GIN_POSTGRES_NAME, self._background_reindex_gin_search
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)
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@defer.inlineCallbacks
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def _background_reindex_search(self, progress, batch_size):
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# we work through the events table from highest stream id to lowest
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target_min_stream_id = progress["target_min_stream_id_inclusive"]
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max_stream_id = progress["max_stream_id_exclusive"]
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rows_inserted = progress.get("rows_inserted", 0)
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TYPES = ["m.room.name", "m.room.message", "m.room.topic"]
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def reindex_search_txn(txn):
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sql = (
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"SELECT stream_ordering, event_id, room_id, type, json, "
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" origin_server_ts FROM events"
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" JOIN event_json USING (room_id, event_id)"
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" WHERE ? <= stream_ordering AND stream_ordering < ?"
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" AND (%s)"
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" ORDER BY stream_ordering DESC"
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" LIMIT ?"
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) % (" OR ".join("type = '%s'" % (t,) for t in TYPES),)
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txn.execute(sql, (target_min_stream_id, max_stream_id, batch_size))
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# we could stream straight from the results into
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# store_search_entries_txn with a generator function, but that
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# would mean having two cursors open on the database at once.
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# Instead we just build a list of results.
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rows = self.cursor_to_dict(txn)
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if not rows:
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return 0
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min_stream_id = rows[-1]["stream_ordering"]
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event_search_rows = []
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for row in rows:
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try:
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event_id = row["event_id"]
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room_id = row["room_id"]
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etype = row["type"]
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stream_ordering = row["stream_ordering"]
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origin_server_ts = row["origin_server_ts"]
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try:
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event_json = json.loads(row["json"])
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content = event_json["content"]
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except Exception:
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continue
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if etype == "m.room.message":
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key = "content.body"
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value = content["body"]
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elif etype == "m.room.topic":
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key = "content.topic"
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value = content["topic"]
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elif etype == "m.room.name":
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key = "content.name"
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value = content["name"]
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else:
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raise Exception("unexpected event type %s" % etype)
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except (KeyError, AttributeError):
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# If the event is missing a necessary field then
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# skip over it.
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continue
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if not isinstance(value, string_types):
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# If the event body, name or topic isn't a string
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# then skip over it
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continue
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event_search_rows.append(
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SearchEntry(
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key=key,
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value=value,
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event_id=event_id,
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room_id=room_id,
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stream_ordering=stream_ordering,
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origin_server_ts=origin_server_ts,
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)
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)
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self.store_search_entries_txn(txn, event_search_rows)
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progress = {
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"target_min_stream_id_inclusive": target_min_stream_id,
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"max_stream_id_exclusive": min_stream_id,
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"rows_inserted": rows_inserted + len(event_search_rows),
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}
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self._background_update_progress_txn(
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txn, self.EVENT_SEARCH_UPDATE_NAME, progress
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)
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return len(event_search_rows)
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result = yield self.runInteraction(
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self.EVENT_SEARCH_UPDATE_NAME, reindex_search_txn
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)
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if not result:
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yield self._end_background_update(self.EVENT_SEARCH_UPDATE_NAME)
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defer.returnValue(result)
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@defer.inlineCallbacks
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def _background_reindex_gin_search(self, progress, batch_size):
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"""This handles old synapses which used GIST indexes, if any;
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converting them back to be GIN as per the actual schema.
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"""
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def create_index(conn):
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conn.rollback()
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# we have to set autocommit, because postgres refuses to
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# CREATE INDEX CONCURRENTLY without it.
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conn.set_session(autocommit=True)
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try:
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c = conn.cursor()
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# if we skipped the conversion to GIST, we may already/still
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# have an event_search_fts_idx; unfortunately postgres 9.4
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# doesn't support CREATE INDEX IF EXISTS so we just catch the
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# exception and ignore it.
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import psycopg2
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try:
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c.execute(
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"CREATE INDEX CONCURRENTLY event_search_fts_idx"
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" ON event_search USING GIN (vector)"
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)
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except psycopg2.ProgrammingError as e:
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logger.warn(
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"Ignoring error %r when trying to switch from GIST to GIN", e
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)
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# we should now be able to delete the GIST index.
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c.execute("DROP INDEX IF EXISTS event_search_fts_idx_gist")
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finally:
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conn.set_session(autocommit=False)
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if isinstance(self.database_engine, PostgresEngine):
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yield self.runWithConnection(create_index)
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yield self._end_background_update(self.EVENT_SEARCH_USE_GIN_POSTGRES_NAME)
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defer.returnValue(1)
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@defer.inlineCallbacks
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def _background_reindex_search_order(self, progress, batch_size):
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target_min_stream_id = progress["target_min_stream_id_inclusive"]
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max_stream_id = progress["max_stream_id_exclusive"]
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rows_inserted = progress.get("rows_inserted", 0)
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have_added_index = progress['have_added_indexes']
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if not have_added_index:
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def create_index(conn):
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conn.rollback()
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conn.set_session(autocommit=True)
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c = conn.cursor()
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# We create with NULLS FIRST so that when we search *backwards*
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# we get the ones with non null origin_server_ts *first*
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c.execute(
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"CREATE INDEX CONCURRENTLY event_search_room_order ON event_search("
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"room_id, origin_server_ts NULLS FIRST, stream_ordering NULLS FIRST)"
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)
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c.execute(
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"CREATE INDEX CONCURRENTLY event_search_order ON event_search("
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"origin_server_ts NULLS FIRST, stream_ordering NULLS FIRST)"
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)
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conn.set_session(autocommit=False)
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yield self.runWithConnection(create_index)
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pg = dict(progress)
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pg["have_added_indexes"] = True
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yield self.runInteraction(
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self.EVENT_SEARCH_ORDER_UPDATE_NAME,
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self._background_update_progress_txn,
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self.EVENT_SEARCH_ORDER_UPDATE_NAME,
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pg,
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)
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def reindex_search_txn(txn):
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sql = (
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"UPDATE event_search AS es SET stream_ordering = e.stream_ordering,"
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" origin_server_ts = e.origin_server_ts"
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" FROM events AS e"
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" WHERE e.event_id = es.event_id"
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" AND ? <= e.stream_ordering AND e.stream_ordering < ?"
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" RETURNING es.stream_ordering"
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)
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min_stream_id = max_stream_id - batch_size
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txn.execute(sql, (min_stream_id, max_stream_id))
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rows = txn.fetchall()
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if min_stream_id < target_min_stream_id:
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# We've recached the end.
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return len(rows), False
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progress = {
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"target_min_stream_id_inclusive": target_min_stream_id,
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"max_stream_id_exclusive": min_stream_id,
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"rows_inserted": rows_inserted + len(rows),
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"have_added_indexes": True,
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}
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self._background_update_progress_txn(
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txn, self.EVENT_SEARCH_ORDER_UPDATE_NAME, progress
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)
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return len(rows), True
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num_rows, finished = yield self.runInteraction(
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self.EVENT_SEARCH_ORDER_UPDATE_NAME, reindex_search_txn
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)
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if not finished:
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yield self._end_background_update(self.EVENT_SEARCH_ORDER_UPDATE_NAME)
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defer.returnValue(num_rows)
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def store_event_search_txn(self, txn, event, key, value):
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"""Add event to the search table
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Args:
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txn (cursor):
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event (EventBase):
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key (str):
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value (str):
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"""
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self.store_search_entries_txn(
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txn,
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(
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SearchEntry(
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key=key,
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value=value,
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event_id=event.event_id,
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room_id=event.room_id,
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stream_ordering=event.internal_metadata.stream_ordering,
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origin_server_ts=event.origin_server_ts,
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),
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),
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)
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def store_search_entries_txn(self, txn, entries):
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"""Add entries to the search table
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Args:
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txn (cursor):
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entries (iterable[SearchEntry]):
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entries to be added to the table
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"""
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if not self.hs.config.enable_search:
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return
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if isinstance(self.database_engine, PostgresEngine):
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sql = (
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"INSERT INTO event_search"
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" (event_id, room_id, key, vector, stream_ordering, origin_server_ts)"
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" VALUES (?,?,?,to_tsvector('english', ?),?,?)"
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)
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args = (
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(
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entry.event_id,
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entry.room_id,
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entry.key,
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entry.value,
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entry.stream_ordering,
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entry.origin_server_ts,
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)
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for entry in entries
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)
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# inserts to a GIN index are normally batched up into a pending
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# list, and then all committed together once the list gets to a
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# certain size. The trouble with that is that postgres (pre-9.5)
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# uses work_mem to determine the length of the list, and work_mem
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# is typically very large.
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#
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# We therefore reduce work_mem while we do the insert.
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#
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# (postgres 9.5 uses the separate gin_pending_list_limit setting,
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# so doesn't suffer the same problem, but changing work_mem will
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# be harmless)
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#
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# Note that we don't need to worry about restoring it on
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# exception, because exceptions will cause the transaction to be
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# rolled back, including the effects of the SET command.
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#
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# Also: we use SET rather than SET LOCAL because there's lots of
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# other stuff going on in this transaction, which want to have the
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# normal work_mem setting.
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txn.execute("SET work_mem='256kB'")
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txn.executemany(sql, args)
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txn.execute("RESET work_mem")
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elif isinstance(self.database_engine, Sqlite3Engine):
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sql = (
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"INSERT INTO event_search (event_id, room_id, key, value)"
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" VALUES (?,?,?,?)"
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)
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args = (
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(entry.event_id, entry.room_id, entry.key, entry.value)
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for entry in entries
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)
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txn.executemany(sql, args)
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else:
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# This should be unreachable.
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raise Exception("Unrecognized database engine")
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@defer.inlineCallbacks
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def search_msgs(self, room_ids, search_term, keys):
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"""Performs a full text search over events with given keys.
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Args:
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room_ids (list): List of room ids to search in
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search_term (str): Search term to search for
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keys (list): List of keys to search in, currently supports
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"content.body", "content.name", "content.topic"
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Returns:
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list of dicts
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"""
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clauses = []
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search_query = search_query = _parse_query(self.database_engine, search_term)
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args = []
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# Make sure we don't explode because the person is in too many rooms.
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# We filter the results below regardless.
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if len(room_ids) < 500:
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clauses.append("room_id IN (%s)" % (",".join(["?"] * len(room_ids)),))
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args.extend(room_ids)
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local_clauses = []
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for key in keys:
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local_clauses.append("key = ?")
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args.append(key)
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clauses.append("(%s)" % (" OR ".join(local_clauses),))
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count_args = args
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count_clauses = clauses
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if isinstance(self.database_engine, PostgresEngine):
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sql = (
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"SELECT ts_rank_cd(vector, to_tsquery('english', ?)) AS rank,"
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" room_id, event_id"
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" FROM event_search"
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" WHERE vector @@ to_tsquery('english', ?)"
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)
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args = [search_query, search_query] + args
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count_sql = (
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"SELECT room_id, count(*) as count FROM event_search"
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" WHERE vector @@ to_tsquery('english', ?)"
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)
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count_args = [search_query] + count_args
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elif isinstance(self.database_engine, Sqlite3Engine):
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sql = (
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"SELECT rank(matchinfo(event_search)) as rank, room_id, event_id"
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" FROM event_search"
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" WHERE value MATCH ?"
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)
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args = [search_query] + args
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count_sql = (
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"SELECT room_id, count(*) as count FROM event_search"
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" WHERE value MATCH ?"
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)
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count_args = [search_term] + count_args
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else:
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# This should be unreachable.
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raise Exception("Unrecognized database engine")
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for clause in clauses:
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sql += " AND " + clause
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for clause in count_clauses:
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count_sql += " AND " + clause
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# We add an arbitrary limit here to ensure we don't try to pull the
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# entire table from the database.
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sql += " ORDER BY rank DESC LIMIT 500"
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results = yield self._execute("search_msgs", self.cursor_to_dict, sql, *args)
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results = list(filter(lambda row: row["room_id"] in room_ids, results))
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events = yield self.get_events_as_list([r["event_id"] for r in results])
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event_map = {ev.event_id: ev for ev in events}
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highlights = None
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if isinstance(self.database_engine, PostgresEngine):
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highlights = yield self._find_highlights_in_postgres(search_query, events)
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count_sql += " GROUP BY room_id"
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count_results = yield self._execute(
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"search_rooms_count", self.cursor_to_dict, count_sql, *count_args
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)
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count = sum(row["count"] for row in count_results if row["room_id"] in room_ids)
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defer.returnValue(
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{
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"results": [
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{"event": event_map[r["event_id"]], "rank": r["rank"]}
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for r in results
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if r["event_id"] in event_map
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],
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"highlights": highlights,
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"count": count,
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}
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)
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@defer.inlineCallbacks
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def search_rooms(self, room_ids, search_term, keys, limit, pagination_token=None):
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"""Performs a full text search over events with given keys.
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Args:
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room_id (list): The room_ids to search in
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search_term (str): Search term to search for
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keys (list): List of keys to search in, currently supports
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"content.body", "content.name", "content.topic"
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pagination_token (str): A pagination token previously returned
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Returns:
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list of dicts
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"""
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clauses = []
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search_query = search_query = _parse_query(self.database_engine, search_term)
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args = []
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# Make sure we don't explode because the person is in too many rooms.
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# We filter the results below regardless.
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if len(room_ids) < 500:
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clauses.append("room_id IN (%s)" % (",".join(["?"] * len(room_ids)),))
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args.extend(room_ids)
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local_clauses = []
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for key in keys:
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local_clauses.append("key = ?")
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args.append(key)
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clauses.append("(%s)" % (" OR ".join(local_clauses),))
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# take copies of the current args and clauses lists, before adding
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# pagination clauses to main query.
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count_args = list(args)
|
|
count_clauses = list(clauses)
|
|
|
|
if pagination_token:
|
|
try:
|
|
origin_server_ts, stream = pagination_token.split(",")
|
|
origin_server_ts = int(origin_server_ts)
|
|
stream = int(stream)
|
|
except Exception:
|
|
raise SynapseError(400, "Invalid pagination token")
|
|
|
|
clauses.append(
|
|
"(origin_server_ts < ?"
|
|
" OR (origin_server_ts = ? AND stream_ordering < ?))"
|
|
)
|
|
args.extend([origin_server_ts, origin_server_ts, stream])
|
|
|
|
if isinstance(self.database_engine, PostgresEngine):
|
|
sql = (
|
|
"SELECT ts_rank_cd(vector, to_tsquery('english', ?)) as rank,"
|
|
" origin_server_ts, stream_ordering, room_id, event_id"
|
|
" FROM event_search"
|
|
" WHERE vector @@ to_tsquery('english', ?) AND "
|
|
)
|
|
args = [search_query, search_query] + args
|
|
|
|
count_sql = (
|
|
"SELECT room_id, count(*) as count FROM event_search"
|
|
" WHERE vector @@ to_tsquery('english', ?) AND "
|
|
)
|
|
count_args = [search_query] + count_args
|
|
elif isinstance(self.database_engine, Sqlite3Engine):
|
|
# We use CROSS JOIN here to ensure we use the right indexes.
|
|
# https://sqlite.org/optoverview.html#crossjoin
|
|
#
|
|
# We want to use the full text search index on event_search to
|
|
# extract all possible matches first, then lookup those matches
|
|
# in the events table to get the topological ordering. We need
|
|
# to use the indexes in this order because sqlite refuses to
|
|
# MATCH unless it uses the full text search index
|
|
sql = (
|
|
"SELECT rank(matchinfo) as rank, room_id, event_id,"
|
|
" origin_server_ts, stream_ordering"
|
|
" FROM (SELECT key, event_id, matchinfo(event_search) as matchinfo"
|
|
" FROM event_search"
|
|
" WHERE value MATCH ?"
|
|
" )"
|
|
" CROSS JOIN events USING (event_id)"
|
|
" WHERE "
|
|
)
|
|
args = [search_query] + args
|
|
|
|
count_sql = (
|
|
"SELECT room_id, count(*) as count FROM event_search"
|
|
" WHERE value MATCH ? AND "
|
|
)
|
|
count_args = [search_term] + count_args
|
|
else:
|
|
# This should be unreachable.
|
|
raise Exception("Unrecognized database engine")
|
|
|
|
sql += " AND ".join(clauses)
|
|
count_sql += " AND ".join(count_clauses)
|
|
|
|
# We add an arbitrary limit here to ensure we don't try to pull the
|
|
# entire table from the database.
|
|
if isinstance(self.database_engine, PostgresEngine):
|
|
sql += (
|
|
" ORDER BY origin_server_ts DESC NULLS LAST,"
|
|
" stream_ordering DESC NULLS LAST LIMIT ?"
|
|
)
|
|
elif isinstance(self.database_engine, Sqlite3Engine):
|
|
sql += " ORDER BY origin_server_ts DESC, stream_ordering DESC LIMIT ?"
|
|
else:
|
|
raise Exception("Unrecognized database engine")
|
|
|
|
args.append(limit)
|
|
|
|
results = yield self._execute("search_rooms", self.cursor_to_dict, sql, *args)
|
|
|
|
results = list(filter(lambda row: row["room_id"] in room_ids, results))
|
|
|
|
events = yield self.get_events_as_list([r["event_id"] for r in results])
|
|
|
|
event_map = {ev.event_id: ev for ev in events}
|
|
|
|
highlights = None
|
|
if isinstance(self.database_engine, PostgresEngine):
|
|
highlights = yield self._find_highlights_in_postgres(search_query, events)
|
|
|
|
count_sql += " GROUP BY room_id"
|
|
|
|
count_results = yield self._execute(
|
|
"search_rooms_count", self.cursor_to_dict, count_sql, *count_args
|
|
)
|
|
|
|
count = sum(row["count"] for row in count_results if row["room_id"] in room_ids)
|
|
|
|
defer.returnValue(
|
|
{
|
|
"results": [
|
|
{
|
|
"event": event_map[r["event_id"]],
|
|
"rank": r["rank"],
|
|
"pagination_token": "%s,%s"
|
|
% (r["origin_server_ts"], r["stream_ordering"]),
|
|
}
|
|
for r in results
|
|
if r["event_id"] in event_map
|
|
],
|
|
"highlights": highlights,
|
|
"count": count,
|
|
}
|
|
)
|
|
|
|
def _find_highlights_in_postgres(self, search_query, events):
|
|
"""Given a list of events and a search term, return a list of words
|
|
that match from the content of the event.
|
|
|
|
This is used to give a list of words that clients can match against to
|
|
highlight the matching parts.
|
|
|
|
Args:
|
|
search_query (str)
|
|
events (list): A list of events
|
|
|
|
Returns:
|
|
deferred : A set of strings.
|
|
"""
|
|
|
|
def f(txn):
|
|
highlight_words = set()
|
|
for event in events:
|
|
# As a hack we simply join values of all possible keys. This is
|
|
# fine since we're only using them to find possible highlights.
|
|
values = []
|
|
for key in ("body", "name", "topic"):
|
|
v = event.content.get(key, None)
|
|
if v:
|
|
values.append(v)
|
|
|
|
if not values:
|
|
continue
|
|
|
|
value = " ".join(values)
|
|
|
|
# We need to find some values for StartSel and StopSel that
|
|
# aren't in the value so that we can pick results out.
|
|
start_sel = "<"
|
|
stop_sel = ">"
|
|
|
|
while start_sel in value:
|
|
start_sel += "<"
|
|
while stop_sel in value:
|
|
stop_sel += ">"
|
|
|
|
query = "SELECT ts_headline(?, to_tsquery('english', ?), %s)" % (
|
|
_to_postgres_options(
|
|
{
|
|
"StartSel": start_sel,
|
|
"StopSel": stop_sel,
|
|
"MaxFragments": "50",
|
|
}
|
|
)
|
|
)
|
|
txn.execute(query, (value, search_query))
|
|
headline, = txn.fetchall()[0]
|
|
|
|
# Now we need to pick the possible highlights out of the haedline
|
|
# result.
|
|
matcher_regex = "%s(.*?)%s" % (
|
|
re.escape(start_sel),
|
|
re.escape(stop_sel),
|
|
)
|
|
|
|
res = re.findall(matcher_regex, headline)
|
|
highlight_words.update([r.lower() for r in res])
|
|
|
|
return highlight_words
|
|
|
|
return self.runInteraction("_find_highlights", f)
|
|
|
|
|
|
def _to_postgres_options(options_dict):
|
|
return "'%s'" % (",".join("%s=%s" % (k, v) for k, v in options_dict.items()),)
|
|
|
|
|
|
def _parse_query(database_engine, search_term):
|
|
"""Takes a plain unicode string from the user and converts it into a form
|
|
that can be passed to database.
|
|
We use this so that we can add prefix matching, which isn't something
|
|
that is supported by default.
|
|
"""
|
|
|
|
# Pull out the individual words, discarding any non-word characters.
|
|
results = re.findall(r"([\w\-]+)", search_term, re.UNICODE)
|
|
|
|
if isinstance(database_engine, PostgresEngine):
|
|
return " & ".join(result + ":*" for result in results)
|
|
elif isinstance(database_engine, Sqlite3Engine):
|
|
return " & ".join(result + "*" for result in results)
|
|
else:
|
|
# This should be unreachable.
|
|
raise Exception("Unrecognized database engine")
|