text: /**
   * HTTP Cloud Function.
   * This function is exported by index.js, and is executed when
   * you make an HTTP request to the deployed function's endpoint.
   *
   * @param {Object} req Cloud Function request context.
   * @param {Object} res Cloud Function response context.
   */
  exports = module.exports = (req, res) => {
    res.send('user logout');
  };
  