text: // Copyright 2018 Google LLC
  //
  // Licensed under the Apache License, Version 2.0 (the "License");
  // you may not use this file except in compliance with the License.
  // You may obtain a copy of the License at
  //
  //      http://www.apache.org/licenses/LICENSE-2.0
  //
  // Unless required by applicable law or agreed to in writing, software
  // distributed under the License is distributed on an "AS IS" BASIS,
  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  // See the License for the specific language governing permissions and
  // limitations under the License.
  
  'use strict';
  
  // [START app]
  const express = require('express');
  const app = express();
  
  app.get('/', (req, res) => {
    res.send('Hello from App Engine!');
  });
  
  // Listen to the App Engine-specified port, or 8080 otherwise
  const PORT = parseInt(process.env.PORT) || 8080;
  app.listen(PORT, () => {
    console.log(`Server listening on port ${PORT}...`);
  });
  // [END app]
  
  module.exports = app;
  