protected function _getOssClient($path)
    {
        if ($this->_oss === null) {
            $url = explode(':', $path);

            if (empty($url)) {
                throw new Exception("Unable to parse URL $path");
            }

            $this->_oss = AliyunOSS::getWrapperClient($url[0]);

            if (!$this->_oss) {
                throw new Exception("Unknown client for wrapper {$url[0]}");
            }
        }

        return $this->_oss;
    }