code: func PostXML(uri string, obj interface{}) ([]byte, error) {
  	xmlData, err := xml.Marshal(obj)
  	if err != nil {
  		return nil, err
  	}
  
  	body := bytes.NewBuffer(xmlData)
  	response, err := http.Post(uri, "application/xml;charset=utf-8", body)
  	if err != nil {
  		return nil, err
  	}
  	defer response.Body.Close()
  
  	if response.StatusCode != http.StatusOK {
  		return nil, fmt.Errorf("http code error : uri=%v , statusCode=%v", uri, response.StatusCode)
  	}
  	return ioutil.ReadAll(response.Body)
  }
docs: //PostXML perform a HTTP/POST request with XML body