code: function RequestError(message, url, error, statusCode, body) {
      this.name = 'RequestError';
      this.stack = (new Error()).stack;
  
      /** @member {String} error message */
      this.message = message;
      /** @member {String} request URL */
      this.url = url;
      /** @member optional error cause */
      this.error = error;
      /** @member {Integer} response status code, if received */
      this.statusCode = statusCode;
      /** @member {String} response body, if received */
      this.body = body;
  }
docs: Contains information about an HTTP request error.
  
  @constructor
  @extends Error
  @param {String} message error message
  @param {String} url request URL
  @param [error] optional error cause
  @param {Integer} [statusCode] response status code, if received
  @param {String} [body] response body, if received