private function prepareRequest(Request $request)
 {
     if ($request->hasData()) {
         curl_setopt($this->curl, CURLOPT_POSTFIELDS, $request->getBody());
     }
     curl_setopt($this->curl, CURLOPT_HTTPHEADER, $request->getHeaders());
     if ($this->debug) {
         $request->queryParams['debug'] = '1';
     }
     curl_setopt($this->curl, CURLOPT_URL, $request->getUrl());
     curl_setopt($this->curl, CURLOPT_CUSTOMREQUEST, $request->method);
     curl_setopt($this->curl, CURLOPT_USERAGENT, $request->getUserAgent());
 }