docs: function xerrorHandler (res, err) {
    logger.log(err, `Error: ${err.code} - ${err.message}`);
  
    const httpCode = err.httpCode || 500;
    const httpResponse = { code: err.code };
    if (isObject(err.httpResponse)) return res.status(httpCode).send(err.httpResponse);
  
    if (isString(err.httpResponse)) httpResponse.message = err.httpResponse;
    return res.status(httpCode).send(httpResponse);
  }