Nodejs Express router.get('/') in users.js - node.js

Question

I m still trying to learn NodeJs but I came across this path thing I encountered in Express. When I create an app using Express I noticed that in app.js I have these lines of code var index = require('./routes/index');
var users = require('./routes/users');
app.use('/', index);
app.use('/users', users);
And in users.js I already have configured
var express = require('express');
var router = express.Router();
/* GET users listing. */
router.get('/', function(req, res, next) {
res.send('respond with a resource');
});
module.exports = router;
I don t really understand why is it in users.js router.get('/') instead of router.get('/users') as it is specified in app.js? Can someone explain a bit what s going on in this case?
As far as I understand in app.js it says whenever someone tries to access the specified route('/users') lets say localhost:3000/users in the browser, let the file required in users variable handle it.

Answer 1

If you are working with routes the express app is automatically . Here is an example from the express.js website:
In our router file we have:
var express = require('express')
var router = express.Router()
// middleware that is specific to this router
router.use(function timeLog (req, res, next) {
console.log('Time: ', Date.now())
next()
})
// define the home page route
router.get('/', function (req, res) {
res.send('Birds home page')
})
// define the about route
router.get('/about', function (req, res) {
res.send('About birds')
})
module.exports = router
Then in our main file were we have our server etc we load in the router:
var birds = require('./birds')
// ...
app.use('/birds', birds)
These routes in the router app are only accessed when there is a request to to /birds url. All the routes in the router are now automatically staring with /birds
So this code in the express router:
// im code in the birds router
router.get('/about', function (req, res) {
res.send('About birds')
})
Is only executed when someone makes a get request to the /birds/about url.
More information in the official express.js docs

Answer 2

I would just like to point out what I have learnt today after some frustration, and maybe somebody can elaborate as to why this happens. Anyway, if, like me, you want to use '/users' for all user routes or '/admin' for all administrator routes then, as WillemvanderVeen mentioned above, you need to add the following code to your main app.js file
var users = require('./routes/users')
app.use('/users', users)
However, one thing which was not mentioned is that the order with which you declare your 'app.use('/users', users)' in app.js is important. For example, you would have two route handling files as so:
/routes/index.js
const express = require('express');
const router = express.Router();
router.get('/', (req, res) => { res.render('index') });
/routes/users.js
const express = require('express'); const router = express.Router();
router.get('/', (req, res) => { res.send('users route') })
You would then require them in your main app.js file as so:
app.js
const express = require('express');
const app = express();
const index = require('./routes/index');
const users = require('./routes/users');
app.use('/', index);
app.use('/users', users);
and you would expect that when you hit the '/users' route that you would receive the res.send('users route') page.
This did not work for me, and I struggled to find any solution until recently, which is why I am now commenting to help you.
Instead, I swapped the app.use() declarations in app.js around like so and it worked:
app.js
const express = require('express');
const app = express();
const index = require('./routes/index');
const users = require('./routes/users');
app.use('/users', users);
app.use('/', index);
Now when I hit '/users' I see the 'users route' message. Hope this helped.
To answer your question though, when you configure the route handler in app.js as users, then you are requiring a router file (./routes/users) to handle all requests from that file and sending them to the URL /users first. So if you do the following:
/routes/users.js
router.get('/dashboard', (req, res) => {
// get user data based on id and render it
res.render('dashboard')
});
then whenever user is logged in and goes to dashboard, the URL will be /users/dashboard.