Nodejs/Express Session - Error: Can't set headers after they are sent

Question

I am getting the below error while trying to use express session with a simple nodejs sample app.

When "resave" is set to true the below error appears, however when the same is set to false, there is no error.

GET / 304 13.380 ms - - Error: Can't set headers after they are sent. at ServerResponse.OutgoingMessage.setHeader (_http_outgoing.js:344:11) at ServerResponse.header (/Volumes/SURESH/GSKLabs/NodeApp/node_modules/express/lib/response.js:718:10) at ServerResponse.contentType (/Volumes/SURESH/GSKLabs/NodeApp/node_modules/express/lib/response.js:551:15) at ServerResponse.send (/Volumes/SURESH/GSKLabs/NodeApp/node_modules/express/lib/response.js:138:14) at done (/Volumes/SURESH/GSKLabs/NodeApp/node_modules/express/lib/response.js:957:10)

Below is the code app.js

var express = require('express');
var session = require('express-session');
var path = require('path');
var favicon = require('serve-favicon');
var logger = require('morgan');
var cookieParser = require('cookie-parser');
var bodyParser = require('body-parser');

var mongojs = require('mongojs');
var mongoStore = require('connect-mongo')(session);
var db = mongojs('mongodb://localhost:27017/checker', ['sessions']);

var routes = require('./routes/index');

var app = express();

// view engine setup
app.set('views', path.join(__dirname, 'views'));
app.set('view engine', 'ejs');

var sessionStore = new mongoStore({
  db: db,

})

// Session details
app.use(session({
  secret: 'check first',
  name: {secure: true, maxAge: 60000},
  store: sessionStore,  // connect-mongo session store
  proxy: true,
  resave: true,
  saveUninitialized: true
}));

// uncomment after placing your favicon in /public
//app.use(favicon(path.join(__dirname, 'public', 'favicon.ico')));
app.use(logger('dev'));
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({ extended: false }));
app.use(cookieParser());
app.use(express.static(path.join(__dirname, 'public')));

app.use('/', routes);

// catch 404 and forward to error handler
app.use(function(req, res, next) {
  var err = new Error('Not Found');
  err.status = 404;
  next(err);
});

// error handlers

// development error handler
// will print stacktrace/Volumes/SURESH/GSKLabs/NodeApp/node_modules/express/lib/router/index.js:310:13
if (app.get('env') === 'development') {
  app.use(function(err, req, res, next) {
    res.status(err.status || 500);
      res.render('error', {
      message: err.message,
      error: err
    });
  });
}

// production error handler
// no stacktraces leaked to user
app.use(function (err, req, res, next) {
    res.status(err.status || 500);
    res.render('error', {
        message: err.message,
        error: {}
    });
});

module.exports = app;

routes/index.js

var express = require('express');
var router = express.Router();

/* GET home page. */
router.get('/', function(req, res, next) {
    res.render('index', { title: 'Express' });
});

module.exports = router;

package.json

{
  "name": "NodeApp",
  "version": "0.0.0",
  "private": true,
  "scripts": {
    "start": "node ./bin/www"
  },
  "dependencies": {
    "body-parser": "~1.15.1",
    "connect-mongo": "^1.3.2",
    "cookie-parser": "~1.4.3",
    "debug": "~2.2.0",
    "ejs": "~2.4.1",
    "express": "~4.13.4",
    "express-session": "^1.14.1",
    "mongojs": "^2.4.0",
    "morgan": "~1.7.0",
    "serve-favicon": "~2.3.0"
  }
}

As per my understanding, since the resave:true, express session trying to set the cookie after the response is already sent. Cannot change to resave:false, as it needs to be "true" for using rolling option in express session.

Any help how to solve this error in the above sample code. Thanks.