Method RegisterUpdateHook

db/db.go:461–512

RegisterUpdateHook registers a callback that is called when a row is modified in the database. If a callback is already registered, it is replaced. If hook is nil, the callback is removed.

(hook UpdateHookCallback)

// in the database. If a callback is already registered, it is replaced. If hook is nil,
// the callback is removed.
func (db *DB) RegisterUpdateHook(hook UpdateHookCallback) error {
	// Convert from SQLite hook data to rqlite hook data.
	convertFn := func(op int, _, table string, rowID int64) (*command.UpdateHookEvent, error) {
		he := &command.UpdateHookEvent{
			Table: table,
			RowId: rowID,
		}

		switch op {
		case sqlite3.SQLITE_INSERT:
			he.Op = command.UpdateHookEvent_INSERT
		case sqlite3.SQLITE_UPDATE:
			he.Op = command.UpdateHookEvent_UPDATE
		case sqlite3.SQLITE_DELETE:
			he.Op = command.UpdateHookEvent_DELETE
		default:
			return nil, fmt.Errorf("unknown update hook operation %d", op)
		}
		return he, nil
	}

	// Register the callback with the SQLite connection.
	var cb func(int, string, string, int64)
	if hook != nil {
		cb = func(op int, dbName, tblName string, rowID int64) {
			stats.Add(numUpdateHooks, 1)
			ev, err := convertFn(op, dbName, tblName, rowID)
			if err != nil {
				stats.Add(numUpdateHooksErrors, 1)
				ev.Error = err.Error()
			}
			if err := hook(ev); err != nil {
				stats.Add(numUpdateHooksCBErrors, 1)
			}
		}
	}
	f := func(driverConn any) error {
		conn := driverConn.(*sqlite3.SQLiteConn)
		conn.RegisterUpdateHook(cb)
		return nil
	}

	conn, err := db.rwDB.Conn(context.Background())
	if err != nil {
		return err
	}
	defer conn.Close()
	if err := conn.Raw(f); err != nil {
		return err
	}
	return nil
}

// CommitHookCallback is a callback function that is called whenever a transaction
// is committed to the database. If the callback returns true the transaction