Golang Txn.AddCommitTrigger Examples

Example #1

File: event_log.go Project: knz/cockroach

// InsertEventRecord inserts a single event into the event log as part of the
// provided transaction.
func (ev EventLogger) InsertEventRecord(
	txn *client.Txn, eventType EventLogType, targetID, reportingID int32, info interface{},
) error {
	// Record event record insertion in local log output.
	txn.AddCommitTrigger(func() {
		log.Infof(txn.Context, "Event: %q, target: %d, info: %+v",
			eventType,
			targetID,
			info)
	})

	const insertEventTableStmt = `
INSERT INTO system.eventlog (
  timestamp, eventType, targetID, reportingID, info
)
VALUES(
  $1, $2, $3, $4, $5
)
`
	args := []interface{}{
		ev.selectEventTimestamp(txn.Proto.Timestamp),
		eventType,
		targetID,
		reportingID,
		nil, // info
	}
	if info != nil {
		infoBytes, err := json.Marshal(info)
		if err != nil {
			return err
		}
		args[4] = string(infoBytes)
	}

	rows, err := ev.ExecuteStatementInTransaction("log-event", txn, insertEventTableStmt, args...)
	if err != nil {
		return err
	}
	if rows != 1 {
		return errors.Errorf("%d rows affected by log insertion; expected exactly one row affected.", rows)
	}
	return nil
}