cookie-test.js

var express = require('express');
var bodyParser = require('body-parser'); // for reading POSTed form data into `req.body`
var expressSession = require('express-session');
var cookieParser = require('cookie-parser'); // the session is stored in a cookie, so we use this to parse it

var app = express();

// must use cookieParser before expressSession
app.use(cookieParser());

app.use(expressSession({secret:'somesecrettokenhere'}));

app.use(bodyParser());

app.get('/', function(req, res){
  var html = '<form action="/" method="post">' +
             'Your name: <input type="text" name="userName"><br>' +
             '<button type="submit">Submit</button>' +
             '</form>';
  if (req.session.userName) {
    html += '<br>Your username from your session is: ' + req.session.userName;
  }
  res.send(html);
});

app.post('/', function(req, res){
  req.session.userName = req.body.userName;
  res.redirect('/');
});

app.listen(80);