title: Query string variables still empty in Express 4
body: <p>Write simple server as suggested here on <a href="https://stackoverflow.com/questions/5710358/how-to-retrieve-post-query-parameters">stackoverflow</a>:</p>
  
  <p><strong>rest_api.js:</strong></p>
  
  <pre><code>const express = require('express');
  const bodyParser = require('body-parser')
  
  // Initialize RESTful server
  const app = express();
  
  app.set('port', (process.env.PORT || 5000));
  app.use(bodyParser.json() );                        // to support JSON-encoded bodies
  app.use(bodyParser.urlencoded({extended: true}));   // to support URL-encoded bodies
  
  // Spin up the server
  app.listen(app.get('port'), function() {
      console.log('running on port', app.get('port'))
  });
  
  app.post('/bookinghandler', function (req, res) {
      let senderId = req.query.sender;
      let email = req.query.email;
      let hotelName = req.query.hotelName;
      let confirmNumber = req.query.confirmNumber;
      let start = req.query.startDate;
      let end = req.query.endDate;
  }
  </code></pre>
  
  <p><strong>app.js:</strong></p>
  
  <pre><code>// This loads the environment variables from the .env file
  require('dotenv-extended').load();
  
  const builder = require('botbuilder');
  const restify = require('restify');
  
  // Setup Restify Server
  var server = restify.createServer();
  server.listen(process.env.port || process.env.PORT || 3978, function () {
     console.log('%s listening to %s', server.name, server.url); 
  });
  
  // Create chat connector for communicating with the Bot Framework Service
  var connector = new builder.ChatConnector({
      appId: process.env.MICROSOFT_APP_ID,
      appPassword: process.env.MICROSOFT_APP_PASSWORD
  });
  
  // Listen for messages from users 
  server.post('/api/messages', connector.listen());
  
  var bot = require("./bot")
  bot.InitializeBot(connector);
  
  // Load REST API module
  var restApi = require("./rest_api");
  </code></pre>
  
  <p>And want to get parameters through query string (sample request in URL: <code>bookinghandler?sender=100000250242810&amp;email=some@email.com&amp;hotelName=Grand Hotel&amp;confirmNumber=654321&amp;startDate=2017-10-11&amp;endDate=2017-10-15</code>). </p>
  
  <p>However <code>req.params</code>, <code>req.param()</code>, <code>req.body</code>, <code>req.query</code> are still empty. What I'm doing wrong? Is it the only way to do it through <a href="https://stackoverflow.com/a/33859650/630169"><code>require('url')</code></a> or <a href="https://stackoverflow.com/a/5710916/630169"><code>require('qs')</code></a>? If I want to it through express only?</p>