Unable to use express sessions in heroku nodejs app - node.js

Question

In my app.js I have:
var express = require('express')
var path = require('path');
var logger = require('morgan');
var cookieParser = require('cookie-parser');
var bodyParser = require('body-parser');
var passport = require('passport');
var LocalStrategy = require('passport-local').Strategy;
var mongo = require('mongodb');
var flash = require('connect-flash');
....
app.use(logger('dev'));
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({ extended: true }));
app.use(cookieParser('3mKay'));
app.use(require('stylus').middleware(path.join(__dirname, 'public')));
app.use(express.session({ secret: 'thisISmyS3cR3t'}));
This crashes with the following message in Heroku.
Error: Most middleware (like session) is no longer bundled with Express and must be installed separately. Please see https://github.com/senchalabs/connect#middleware.
at Function.Object.defineProperty.get (/app/node_modules/express/lib/express.js:89:13)
at Object.<anonymous> (/app/app.js:25:17)
at Module._compile (module.js:456:26)
at Object.Module._extensions..js (module.js:474:10)
at Module.load (module.js:356:32)
at Function.Module._load (module.js:312:12)
at Function.Module.runMain (module.js:497:10)
at startup (node.js:119:16)
at node.js:906:3
I ran so it does exist in the package.json file as well:
npm install express-sessions --save
"dependencies": {
....
"express": "~4.8.6",
"express-session": "^1.8.1",
"passport": "^0.2.1",
"passport-local": "^1.0.0",
....
It works fine when I comment out the
app.use(express.session({ secret: 'thisISmyS3cR3t'}));
And I've also tried variations of the above but it gives the same error message. Any ideas what may be causing this to happen? Something I might have overlooked...

Answer 1

Once you install it, you have to actually use it in your code:
var express = require('express');
var session = require('express-session');
var path = require('path');
var logger = require('morgan');
var cookieParser = require('cookie-parser');
var bodyParser = require('body-parser');
var passport = require('passport');
var LocalStrategy = require('passport-local').Strategy;
var mongo = require('mongodb');
var flash = require('connect-flash');
....
app.use(logger('dev'));
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({ extended: true }));
app.use(cookieParser('3mKay'));
app.use(require('stylus').middleware(path.join(__dirname, 'public')));
app.use(session({ secret: 'thisISmyS3cR3t'}));