public static function classFromRequest(Request $request, $fallbackClass = null)
    {
        /** @var AbstractHandler $handlerClass */
        foreach (static::$handlers as $handlerClass) {
            if ($handlerClass::canBeUsedForRequest($request)) {
                return $handlerClass;
                break;
            }
        }

        if (is_null($fallbackClass)) {
            // the default handler
            return static::$fallbackHandler;
        }

        return $fallbackClass;
    }