Fix the ordering of events in a response to /sync
MODIFY
src/github.com/matrix-org/dendrite/syncapi/storage/output_room_events_table.go
src/github.com/matrix-org/dendrite/syncapi/storage/output_room_events_table.go
@@ -17,6 +17,7 @@ package storage
import (
"context"
"database/sql"
+ "sort"
"github.com/matrix-org/dendrite/roomserver/api"
@@ -65,7 +66,7 @@ const selectEventsSQL = "" +
const selectRecentEventsSQL = "" +
"SELECT id, event_json, device_id, transaction_id FROM syncapi_output_room_events" +
" WHERE room_id = $1 AND id > $2 AND id <= $3" +
- " ORDER BY id ASC LIMIT $4"
+ " ORDER BY id DESC LIMIT $4"
const selectMaxEventIDSQL = "" +
"SELECT MAX(id) FROM syncapi_output_room_events"
@@ -234,6 +235,12 @@ func (s *outputRoomEventsStatements) selectRecentEvents(
if err != nil {
return nil, err
}
+ // The events need to be returned from oldest to latest, which isn't
+ // necessary the way the SQL query returns them, so a sort is necessary to
+ // ensure the events are in the right order in the slice.
+ sort.SliceStable(events, func(i int, j int) bool {
+ return events[i].streamPosition < events[j].streamPosition
+ })
return events, nil
}

Fix the ordering of events in a response to /sync (#588)