public function uploadFile($realPath, $file_name, $file_type, UploadFileParameters $params = null)
    {
        if (is_null($params)) {
            $params = new UploadFileParameters();
        }
        $params = $params->exportToArray();
        $params['file'] = $realPath;
        $params['fileUri'] = $file_name;
        $params['fileType'] = $file_type;

        $requestData = $this->getDefaultRequestData('multipart', $params);

        return $this->sendRequest('file', $requestData, self::HTTP_METHOD_POST);
    }