609 lines
		
	
	
		
			22 KiB
		
	
	
	
		
			Python
		
	
	
			
		
		
	
	
			609 lines
		
	
	
		
			22 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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from twisted.internet import defer
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from .background_updates import BackgroundUpdateStore
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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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import logging
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import re
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import ujson as json
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logger = logging.getLogger(__name__)
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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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    def __init__(self, db_conn, hs):
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        super(SearchStore, self).__init__(db_conn, hs)
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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,
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            self._background_reindex_search_order
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        )
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        self.register_background_update_handler(
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            self.EVENT_SEARCH_USE_GIST_POSTGRES_NAME,
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            self._background_reindex_gist_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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        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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        INSERT_CLUMP_SIZE = 1000
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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, content FROM events"
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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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            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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                    try:
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                        content = json.loads(row["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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                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, basestring):
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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((event_id, room_id, key, value))
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            if isinstance(self.database_engine, PostgresEngine):
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                sql = (
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                    "INSERT INTO event_search (event_id, room_id, key, vector)"
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                    " VALUES (?,?,?,to_tsvector('english', ?))"
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                )
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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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            else:
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                # This should be unreachable.
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                raise Exception("Unrecognized database engine")
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            for index in range(0, len(event_search_rows), INSERT_CLUMP_SIZE):
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                clump = event_search_rows[index:index + INSERT_CLUMP_SIZE]
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                txn.executemany(sql, clump)
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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_gist_search(self, progress, batch_size):
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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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            c.execute(
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                "CREATE INDEX CONCURRENTLY event_search_fts_idx_gist"
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                " ON event_search USING GIST (vector)"
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            )
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            c.execute("DROP INDEX event_search_fts_idx")
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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_GIST_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, 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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    @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(
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                "room_id IN (%s)" % (",".join(["?"] * len(room_ids)),)
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            )
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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(
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            "(%s)" % (" OR ".join(local_clauses),)
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        )
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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(
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            "search_msgs", self.cursor_to_dict, sql, *args
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        )
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        results = filter(lambda row: row["room_id"] in room_ids, results)
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        events = yield self._get_events([r["event_id"] for r in results])
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        event_map = {
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            ev.event_id: ev
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            for ev in events
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        }
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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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            "results": [
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                {
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                    "event": event_map[r["event_id"]],
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                    "rank": r["rank"],
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                }
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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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    @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(
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                "room_id IN (%s)" % (",".join(["?"] * len(room_ids)),)
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            )
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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(
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            "(%s)" % (" OR ".join(local_clauses),)
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        )
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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)
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        count_clauses = list(clauses)
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        if pagination_token:
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            try:
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                origin_server_ts, stream = pagination_token.split(",")
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                origin_server_ts = int(origin_server_ts)
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                stream = int(stream)
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            except Exception:
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                raise SynapseError(400, "Invalid pagination token")
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            clauses.append(
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                "(origin_server_ts < ?"
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                " OR (origin_server_ts = ? AND stream_ordering < ?))"
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            )
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            args.extend([origin_server_ts, origin_server_ts, stream])
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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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                " origin_server_ts, stream_ordering, room_id, event_id"
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                " FROM event_search"
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                " WHERE vector @@ to_tsquery('english', ?) AND "
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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', ?) AND "
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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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            # We use CROSS JOIN here to ensure we use the right indexes.
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            # https://sqlite.org/optoverview.html#crossjoin
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            #
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            # We want to use the full text search index on event_search to
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            # extract all possible matches first, then lookup those matches
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            # in the events table to get the topological ordering. We need
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            # to use the indexes in this order because sqlite refuses to
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            # MATCH unless it uses the full text search index
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            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 = filter(lambda row: row["room_id"] in room_ids, results)
 | 
						|
 | 
						|
        events = yield self._get_events([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")
 |