code: func HTTPGet(uri string) ([]byte, error) {
  	response, err := http.Get(uri)
  	if err != nil {
  		return nil, err
  	}
  
  	defer response.Body.Close()
  	if response.StatusCode != http.StatusOK {
  		return nil, fmt.Errorf("http get error : uri=%v , statusCode=%v", uri, response.StatusCode)
  	}
  	return ioutil.ReadAll(response.Body)
  }
docs: //HTTPGet get 请求