node js jwt login exapmle

https://www.fullstacktutorials.com/interviews/top-10-express-js-interview-questions-answers-30.html

1. router.post('/login, function(req, res) {
2.   // find the user
3.   User.findOne({
4.     name: req.body.username
5.   }, function(err, res) {
6.     if (err) throw err;
7.     if (!res) {
8.       res.json({ success: false, message: Login failed.' });
9.     } else if (res) {
10. 
    
11.       // check if password matches
12.       if (res.password != req.body.password) {
13.         res.json({ success: false, message: Login  failed. Wrong password.' });
14.       } else {
15.         var token = jwt.sign(res, app.get('superSecret'), {
16.           expiresInMinutes: 1600
17.         });
18.         // return the information including token as JSON
19.         res.json({
20.           success: true,
21.           message: 'Valid token!',
22.           token: token
23.         });
24.       }  
25.    }  });
26. });

1. jwt = require("express-jwt");
2. app.use(function(req, res, next) {
3.   var token = req.body.token || req.query.token || req.headers['x-access-token'];
4.   if (token) {
5.     jwt.verify(token, app.get('superSecret'), function(err, decoded) {     
6.       if (err) {
7.         return res.json({ success: false, message: 'Invalid token.' });   
8.       } else {
9.         req.decoded = decoded;   
10.         next();
11.       }
12.     });
13.   } else {
14.     return res.status(403).send({
15.         success: false,
16.         message: 'No token given.'
17.     });   
18.   }
19. });