Bolt\Controller\ConfigurableBase::resolveBefore PHP Метод

    protected function resolveBefore($before)
    {
        $getBefore = $this->resolveMiddleware($before);
        return function (Request $request, Application $app) use($getBefore) {
            $callback = $getBefore($request);
            if (!is_callable($callback)) {
                return null;
            }
            return call_user_func($callback, $request, $app);
        };
    }