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This commit is contained in:
Neil Alexander 2022-08-01 13:55:19 +01:00
parent f0d3d50dc0
commit ab923987f7
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GPG key ID: A02A2019A2BB0944
2 changed files with 24 additions and 20 deletions

View file

@ -77,21 +77,25 @@ const bulkSelectStateBlockNIDsSQL = "" +
// helpers.CheckServerAllowedToSeeEvent function.
// TODO: There's a sequence scan here because of the hash join strategy, which is
// probably O(n) on state key entries, so there must be a way to avoid that somehow.
const bulkSelectStateForHistoryVisibilitySQL = "" +
"SELECT event_nid FROM (" +
" SELECT event_nid, event_type_nid, event_state_key_nid FROM roomserver_events" +
" WHERE (event_type_nid = 5 OR event_type_nid = 7)" +
" AND event_nid = ANY(" +
" SELECT UNNEST(event_nids) FROM roomserver_state_block" +
" WHERE state_block_nid = ANY(" +
" SELECT UNNEST(state_block_nids) FROM roomserver_state_snapshots" +
" WHERE state_snapshot_nid = $1" +
" )" +
" )" +
") AS roomserver_events" +
" INNER JOIN roomserver_event_state_keys" +
" ON roomserver_events.event_state_key_nid = roomserver_event_state_keys.event_state_key_nid" +
" AND (event_type_nid = 7 OR event_state_key LIKE '%:' || $2);"
// Event type NIDs are:
// - 5: m.room.member as per https://github.com/matrix-org/dendrite/blob/c7f7aec4d07d59120d37d5b16a900f6d608a75c4/roomserver/storage/postgres/event_types_table.go#L40
// - 7: m.room.history_visibility as per https://github.com/matrix-org/dendrite/blob/c7f7aec4d07d59120d37d5b16a900f6d608a75c4/roomserver/storage/postgres/event_types_table.go#L42
const bulkSelectStateForHistoryVisibilitySQL = `
SELECT event_nid FROM (
SELECT event_nid, event_type_nid, event_state_key_nid FROM roomserver_events
WHERE (event_type_nid = 5 OR event_type_nid = 7)
AND event_nid = ANY(
SELECT UNNEST(event_nids) FROM roomserver_state_block
WHERE state_block_nid = ANY(
SELECT UNNEST(state_block_nids) FROM roomserver_state_snapshots
WHERE state_snapshot_nid = $1
)
)
) AS roomserver_events
INNER JOIN roomserver_event_state_keys
ON roomserver_events.event_state_key_nid = roomserver_event_state_keys.event_state_key_nid
AND (event_type_nid = 7 OR event_state_key LIKE '%:' || $2);
`
type stateSnapshotStatements struct {
insertStateStmt *sql.Stmt
@ -170,15 +174,12 @@ func (s *stateSnapshotStatements) BulkSelectStateForHistoryVisibility(
}
defer rows.Close() // nolint: errcheck
results := make([]types.EventNID, 0, 16)
for i := 0; rows.Next(); i++ {
for rows.Next() {
var eventNID types.EventNID
if err = rows.Scan(&eventNID); err != nil {
return nil, err
}
results = append(results, eventNID)
}
if err = rows.Err(); err != nil {
return nil, err
}
return results, nil
return results, rows.Err()
}

View file

@ -83,6 +83,9 @@ type Rooms interface {
type StateSnapshot interface {
InsertState(ctx context.Context, txn *sql.Tx, roomNID types.RoomNID, stateBlockNIDs types.StateBlockNIDs) (stateNID types.StateSnapshotNID, err error)
BulkSelectStateBlockNIDs(ctx context.Context, txn *sql.Tx, stateNIDs []types.StateSnapshotNID) ([]types.StateBlockNIDList, error)
// BulkSelectStateForHistoryVisibility is a PostgreSQL-only optimisation for finding
// which users are in a room faster than having to load the entire room state. In the
// case of SQLite, this will return tables.OptimisationNotSupportedError.
BulkSelectStateForHistoryVisibility(ctx context.Context, txn *sql.Tx, stateSnapshotNID types.StateSnapshotNID, domain string) ([]types.EventNID, error)
}