node-auth-Guard makes use of CanActivate interface and it checks for if the user is logged in or not. If it returns true, then the execution for the requested route will continue, and if it returns false, then the requested route will be kicked off and the default route will be shown..
Now we can consider an example of an Movie streaming platform like Amazon prime, Netflix, Hotstar..etc thats works with auth guard .
🔑 In the example,the user should subscribe or recharge the account to get access to the homepage,
🔑 Then the user should be above the age of 18 to watch certain movies or shows.
Step1 : You need to install express and node-auth-guard in your node as it is not a core module.
npm i express@4.16.4
npm i node-auth-guard@2.4.0
💊 Now the version 4.16.4 of express and 2.4.0 version of node-auth-guard is installed in node.js
step2 : Then , Code your program as
const express=require(‘express’)
let authGuard = require('node-auth-guard');
let app = express();
app.use((req, res, next) => {
req.user ={
subscriber:{
name:'joseph',
surname:'kennedy',
age:16,
subscription:true
}
}
next();
});
app.use(authGuard.initialize({
principalPath: 'user.subscriber',
}));
app.get('/home',
authGuard.rule(
(req, res, next) => {
if (req.user.subscriber.subscription === true) {
return next()
}else {
return next(new Error('Please kindly recharge your account,now'));
}
}
),
(req, res, next) => {
res.end('<h1> hello '+req.user.subscriber.name+ '</h1><br><h2>welcome back!</h2>');
}
);
app.get('/movie',
authGuard.rule(
(req, res, next) => {
if (req.user.subscriber.age >= 18) {
return next()
}else {
return next(new Error(' hi '+req.user.subscriber.name+ ' you are not advised to watch it!'));
}},
),
(req, res, next) => {
res.end('watch movie');
}
);
app.listen(4000);
Step3 : Now go to the browser and enter the URL
http://localhost:4000/home
http://localhost:4000/movie
to see your output.
- To get to know more about express click me
- Now define a user with following properties such as name, surname, age and subscribtion.
- Then initialize the user.
- With the help of express.js create a localhost server \home and \movie
- In http://localhost:4000/home
it checks whether the user has subscribed or not . If not, it throws an error or else it shows the following output:
- In http://localhost:4000/movie
it checks whether the user is above 18. If yes, it shows the output or else it shows the following error:
