# -*- coding: utf-8 -*- # Copyright 2014-2016 OpenMarket Ltd # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. from twisted.internet import defer from ._base import SQLBaseStore from synapse.util.caches.descriptors import cached from unpaddedbase64 import encode_base64 import logging from Queue import PriorityQueue, Empty logger = logging.getLogger(__name__) class EventFederationStore(SQLBaseStore): """ Responsible for storing and serving up the various graphs associated with an event. Including the main event graph and the auth chains for an event. Also has methods for getting the front (latest) and back (oldest) edges of the event graphs. These are used to generate the parents for new events and backfilling from another server respectively. """ def get_auth_chain(self, event_ids): return self.get_auth_chain_ids(event_ids).addCallback(self._get_events) def get_auth_chain_ids(self, event_ids): return self.runInteraction( "get_auth_chain_ids", self._get_auth_chain_ids_txn, event_ids ) def _get_auth_chain_ids_txn(self, txn, event_ids): results = set() base_sql = ( "SELECT auth_id FROM event_auth WHERE event_id IN (%s)" ) front = set(event_ids) while front: new_front = set() front_list = list(front) chunks = [ front_list[x:x + 100] for x in xrange(0, len(front), 100) ] for chunk in chunks: txn.execute( base_sql % (",".join(["?"] * len(chunk)),), chunk ) new_front.update([r[0] for r in txn.fetchall()]) new_front -= results front = new_front results.update(front) return list(results) def get_oldest_events_in_room(self, room_id): return self.runInteraction( "get_oldest_events_in_room", self._get_oldest_events_in_room_txn, room_id, ) def get_oldest_events_with_depth_in_room(self, room_id): return self.runInteraction( "get_oldest_events_with_depth_in_room", self.get_oldest_events_with_depth_in_room_txn, room_id, ) def get_oldest_events_with_depth_in_room_txn(self, txn, room_id): sql = ( "SELECT b.event_id, MAX(e.depth) FROM events as e" " INNER JOIN event_edges as g" " ON g.event_id = e.event_id AND g.room_id = e.room_id" " INNER JOIN event_backward_extremities as b" " ON g.prev_event_id = b.event_id AND g.room_id = b.room_id" " WHERE b.room_id = ? AND g.is_state is ?" " GROUP BY b.event_id" ) txn.execute(sql, (room_id, False,)) return dict(txn.fetchall()) def _get_oldest_events_in_room_txn(self, txn, room_id): return self._simple_select_onecol_txn( txn, table="event_backward_extremities", keyvalues={ "room_id": room_id, }, retcol="event_id", ) def get_latest_events_in_room(self, room_id): return self.runInteraction( "get_latest_events_in_room", self._get_latest_events_in_room, room_id, ) @cached() def get_latest_event_ids_in_room(self, room_id): return self._simple_select_onecol( table="event_forward_extremities", keyvalues={ "room_id": room_id, }, retcol="event_id", desc="get_latest_event_ids_in_room", ) def _get_latest_events_in_room(self, txn, room_id): sql = ( "SELECT e.event_id, e.depth FROM events as e " "INNER JOIN event_forward_extremities as f " "ON e.event_id = f.event_id " "AND e.room_id = f.room_id " "WHERE f.room_id = ?" ) txn.execute(sql, (room_id, )) results = [] for event_id, depth in txn.fetchall(): hashes = self._get_event_reference_hashes_txn(txn, event_id) prev_hashes = { k: encode_base64(v) for k, v in hashes.items() if k == "sha256" } results.append((event_id, prev_hashes, depth)) return results def get_min_depth(self, room_id): """ For hte given room, get the minimum depth we have seen for it. """ return self.runInteraction( "get_min_depth", self._get_min_depth_interaction, room_id, ) def _get_min_depth_interaction(self, txn, room_id): min_depth = self._simple_select_one_onecol_txn( txn, table="room_depth", keyvalues={"room_id": room_id}, retcol="min_depth", allow_none=True, ) return int(min_depth) if min_depth is not None else None def _update_min_depth_for_room_txn(self, txn, room_id, depth): min_depth = self._get_min_depth_interaction(txn, room_id) do_insert = depth < min_depth if min_depth else True if do_insert: self._simple_upsert_txn( txn, table="room_depth", keyvalues={ "room_id": room_id, }, values={ "min_depth": depth, }, ) def _handle_mult_prev_events(self, txn, events): """ For the given event, update the event edges table and forward and backward extremities tables. """ self._simple_insert_many_txn( txn, table="event_edges", values=[ { "event_id": ev.event_id, "prev_event_id": e_id, "room_id": ev.room_id, "is_state": False, } for ev in events for e_id, _ in ev.prev_events ], ) self._update_extremeties(txn, events) def _update_extremeties(self, txn, events): """Updates the event_*_extremities tables based on the new/updated events being persisted. This is called for new events *and* for events that were outliers, but are are now being persisted as non-outliers. """ events_by_room = {} for ev in events: events_by_room.setdefault(ev.room_id, []).append(ev) for room_id, room_events in events_by_room.items(): prevs = [ e_id for ev in room_events for e_id, _ in ev.prev_events if not ev.internal_metadata.is_outlier() ] if prevs: txn.execute( "DELETE FROM event_forward_extremities" " WHERE room_id = ?" " AND event_id in (%s)" % ( ",".join(["?"] * len(prevs)), ), [room_id] + prevs, ) query = ( "INSERT INTO event_forward_extremities (event_id, room_id)" " SELECT ?, ? WHERE NOT EXISTS (" " SELECT 1 FROM event_edges WHERE prev_event_id = ?" " )" ) txn.executemany( query, [ (ev.event_id, ev.room_id, ev.event_id) for ev in events if not ev.internal_metadata.is_outlier() ] ) query = ( "INSERT INTO event_backward_extremities (event_id, room_id)" " SELECT ?, ? WHERE NOT EXISTS (" " SELECT 1 FROM event_backward_extremities" " WHERE event_id = ? AND room_id = ?" " )" " AND NOT EXISTS (" " SELECT 1 FROM events WHERE event_id = ? AND room_id = ? " " AND outlier = ?" " )" ) txn.executemany(query, [ (e_id, ev.room_id, e_id, ev.room_id, e_id, ev.room_id, False) for ev in events for e_id, _ in ev.prev_events if not ev.internal_metadata.is_outlier() ]) query = ( "DELETE FROM event_backward_extremities" " WHERE event_id = ? AND room_id = ?" ) txn.executemany( query, [ (ev.event_id, ev.room_id) for ev in events if not ev.internal_metadata.is_outlier() ] ) for room_id in events_by_room: txn.call_after( self.get_latest_event_ids_in_room.invalidate, (room_id,) ) def get_backfill_events(self, room_id, event_list, limit): """Get a list of Events for a given topic that occurred before (and including) the events in event_list. Return a list of max size `limit` Args: txn room_id (str) event_list (list) limit (int) """ return self.runInteraction( "get_backfill_events", self._get_backfill_events, room_id, event_list, limit ).addCallback( self._get_events ).addCallback( lambda l: sorted(l, key=lambda e: -e.depth) ) def _get_backfill_events(self, txn, room_id, event_list, limit): logger.debug( "_get_backfill_events: %s, %s, %s", room_id, repr(event_list), limit ) event_results = set() # We want to make sure that we do a breadth-first, "depth" ordered # search. query = ( "SELECT depth, prev_event_id FROM event_edges" " INNER JOIN events" " ON prev_event_id = events.event_id" " AND event_edges.room_id = events.room_id" " WHERE event_edges.room_id = ? AND event_edges.event_id = ?" " AND event_edges.is_state = ?" " LIMIT ?" ) queue = PriorityQueue() for event_id in event_list: depth = self._simple_select_one_onecol_txn( txn, table="events", keyvalues={ "event_id": event_id, }, retcol="depth", allow_none=True, ) if depth: queue.put((-depth, event_id)) while not queue.empty() and len(event_results) < limit: try: _, event_id = queue.get_nowait() except Empty: break if event_id in event_results: continue event_results.add(event_id) txn.execute( query, (room_id, event_id, False, limit - len(event_results)) ) for row in txn.fetchall(): if row[1] not in event_results: queue.put((-row[0], row[1])) return event_results @defer.inlineCallbacks def get_missing_events(self, room_id, earliest_events, latest_events, limit, min_depth): ids = yield self.runInteraction( "get_missing_events", self._get_missing_events, room_id, earliest_events, latest_events, limit, min_depth ) events = yield self._get_events(ids) events = sorted( [ev for ev in events if ev.depth >= min_depth], key=lambda e: e.depth, ) defer.returnValue(events[:limit]) def _get_missing_events(self, txn, room_id, earliest_events, latest_events, limit, min_depth): earliest_events = set(earliest_events) front = set(latest_events) - earliest_events event_results = set() query = ( "SELECT prev_event_id FROM event_edges " "WHERE room_id = ? AND event_id = ? AND is_state = ? " "LIMIT ?" ) while front and len(event_results) < limit: new_front = set() for event_id in front: txn.execute( query, (room_id, event_id, False, limit - len(event_results)) ) for e_id, in txn.fetchall(): new_front.add(e_id) new_front -= earliest_events new_front -= event_results front = new_front event_results |= new_front return event_results def clean_room_for_join(self, room_id): return self.runInteraction( "clean_room_for_join", self._clean_room_for_join_txn, room_id, ) def _clean_room_for_join_txn(self, txn, room_id): query = "DELETE FROM event_forward_extremities WHERE room_id = ?" txn.execute(query, (room_id,)) txn.call_after(self.get_latest_event_ids_in_room.invalidate, (room_id,))