From 06c0d0ed081b56716135c4881e600861b2e8cad5 Mon Sep 17 00:00:00 2001 From: Erik Johnston Date: Tue, 8 May 2018 15:45:38 +0100 Subject: [PATCH] Split paginate_room_events storage function --- synapse/storage/stream.py | 100 +++++++++++++++++++++++++++----------- 1 file changed, 72 insertions(+), 28 deletions(-) diff --git a/synapse/storage/stream.py b/synapse/storage/stream.py index f0784ba13..b57a8a7ef 100644 --- a/synapse/storage/stream.py +++ b/synapse/storage/stream.py @@ -738,17 +738,28 @@ class StreamWorkerStore(EventsWorkerStore, SQLBaseStore): def has_room_changed_since(self, room_id, stream_id): return self._events_stream_cache.has_entity_changed(room_id, stream_id) + def paginate_room_events_txn(self, txn, room_id, from_key, to_key=None, + direction='b', limit=-1, event_filter=None): + """Returns list of events before or after a given token. -class StreamStore(StreamWorkerStore): - def get_room_max_stream_ordering(self): - return self._stream_id_gen.get_current_token() + Args: + txn + room_id (str) + from_key (str): The token used to stream from + to_key (str|None): A token which if given limits the results to + only those before + direction(char): Either 'b' or 'f' to indicate whether we are + paginating forwards or backwards from `from_key`. + limit (int): The maximum number of events to return. Zero or less + means no limit. + event_filter (Filter|None): If provided filters the events to + those that match the filter. - def get_room_min_stream_ordering(self): - return self._backfill_id_gen.get_current_token() - - @defer.inlineCallbacks - def paginate_room_events(self, room_id, from_key, to_key=None, - direction='b', limit=-1, event_filter=None): + Returns: + tuple[list[dict], str]: Returns the results as a list of dicts and + a token that points to the end of the result set. The dicts have + the keys "event_id", "toplogical_ordering" and "stream_orderign". + """ # Tokens really represent positions between elements, but we use # the convention of pointing to the event before the gap. Hence # we have a bit of asymmetry when it comes to equalities. @@ -795,29 +806,54 @@ class StreamStore(StreamWorkerStore): "limit": limit_str } - def f(txn): - txn.execute(sql, args) + txn.execute(sql, args) - rows = self.cursor_to_dict(txn) + rows = self.cursor_to_dict(txn) - if rows: - topo = rows[-1]["topological_ordering"] - toke = rows[-1]["stream_ordering"] - if direction == 'b': - # Tokens are positions between events. - # This token points *after* the last event in the chunk. - # We need it to point to the event before it in the chunk - # when we are going backwards so we subtract one from the - # stream part. - toke -= 1 - next_token = str(RoomStreamToken(topo, toke)) - else: - # TODO (erikj): We should work out what to do here instead. - next_token = to_key if to_key else from_key + if rows: + topo = rows[-1]["topological_ordering"] + toke = rows[-1]["stream_ordering"] + if direction == 'b': + # Tokens are positions between events. + # This token points *after* the last event in the chunk. + # We need it to point to the event before it in the chunk + # when we are going backwards so we subtract one from the + # stream part. + toke -= 1 + next_token = str(RoomStreamToken(topo, toke)) + else: + # TODO (erikj): We should work out what to do here instead. + next_token = to_key if to_key else from_key - return rows, next_token, + return rows, next_token, - rows, token = yield self.runInteraction("paginate_room_events", f) + @defer.inlineCallbacks + def paginate_room_events(self, room_id, from_key, to_key=None, + direction='b', limit=-1, event_filter=None): + """Returns list of events before or after a given token. + + Args: + room_id (str) + from_key (str): The token used to stream from + to_key (str|None): A token which if given limits the results to + only those before + direction(char): Either 'b' or 'f' to indicate whether we are + paginating forwards or backwards from `from_key`. + limit (int): The maximum number of events to return. Zero or less + means no limit. + event_filter (Filter|None): If provided filters the events to + those that match the filter. + + Returns: + tuple[list[dict], str]: Returns the results as a list of dicts and + a token that points to the end of the result set. The dicts have + the keys "event_id", "toplogical_ordering" and "stream_orderign". + """ + + rows, token = yield self.runInteraction( + "paginate_room_events", self.paginate_room_events_txn, + room_id, from_key, to_key, direction, limit, event_filter, + ) events = yield self._get_events( [r["event_id"] for r in rows], @@ -827,3 +863,11 @@ class StreamStore(StreamWorkerStore): self._set_before_and_after(events, rows) defer.returnValue((events, token)) + + +class StreamStore(StreamWorkerStore): + def get_room_max_stream_ordering(self): + return self._stream_id_gen.get_current_token() + + def get_room_min_stream_ordering(self): + return self._backfill_id_gen.get_current_token()