index.js

Sometimes it can be useful to split our routes into multiple files for organizational purposes. For instance, we could place all of our user registration and login routes in routes/users.js to make them separate from our main routes.

To do so, you need to register the route file in app.js.

Example:

const indexRouter = require('./routes/index');
const usersRouter = require('./routes/users');

app.use('/', indexRouter);
app.use('/users', usersRouter);

Note that the app.use() method is what defines which URL endpoint that will be used by the router file.

With

app.use('/users', usersRouter)

this means that we will not make reference to “/users” when declaring our routes.

For example,

if the following route is in users.js:

router.get('/register', (req, res) => {
    res.render('register');
}

Then it would be accessed at “/users/register”, not just “/register”.