Can't handle routes using Express - node.js

Question

I'm just starting out and I've got a barebones app here with a routes file ./routes/index.js.
When I browse to http://localhost:3000/index for example index.js is hit but none of the routes match and the program just goes straight through to "return router;". If I browse to http://localhost:3000/ I get the same again.
All the browser does is think about it for a bit and then give me a ERR_CONNECTION_RESET.
app.js
var express = require('express');
var logger = require('morgan');
var bodyParser = require('body-parser');
var mongoose = require('mongoose');
var flash = require('connect-flash');
mongoose.connect('mongodb://localhost/blah');
var app = express();
app.use(logger('dev'));
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({ extended: false }));
app.use(flash());
app.use(require('./routes/index'));
module.exports = app;
index.js
var express = require('express');
var router = express.Router();
function authorize(req, res, next) {
if (true) {
next()
} else {
res.status(403).send('Forbidden')
}
}
module.exports = function(){
router.get('/index', function(req, res) {
res.send('index');
});
router.get('/hello/:name', function(req, res) {
res.send('hello ' + req.params.name + '!');
});
router.get('/', function(req, res) {
res.send('root');
});
return router;
}

Answer 1

app.js is missing a line to actually start the server. You need to add this:
app.listen(3000);

Answer 2

Got there in the end... I changed
module.exports = function(){
router.get('/index', function(req, res) {
res.send('index');
});
router.get('/hello/:name', function(req, res) {
res.send('hello ' + req.params.name + '!');
});
router.get('/', function(req, res) {
res.send('root');
});
return router;
}
to
router.get('/index', function(req, res) {
res.send('index');
});
router.get('/hello/:name', function(req, res) {
res.send('hello ' + req.params.name + '!');
});
router.get('/', function(req, res) {
res.send('root');
});
module.exports = router;