JWT get user details and set expire time - node.js

Question

I am using a JWT token based login system and it is working fine.
But I need to get user details based on JWT token
exports.signin = function(req, res) {
User.findOne({
username: req.body.username
}, function(err, user) {
if (err) throw err;
if (!user || !user.comparePassword(req.body.password)) {
return res.status(401).json({ message: 'Authentication failed. Invalid user or password.' });
}
return res.json({ token: jwt.sign({ email: user.email, username: user.username, _id: user._id }, 'RESTFULAPIs') });
});
};
app.use(function(req, res, next) {
if (req.headers && req.headers.authorization && req.headers.authorization.split(' ')[0] === 'JWT') {
jsonwebtoken.verify(req.headers.authorization.split(' ')[1], 'RESTFULAPIs', function(err, decode) {
if (err) req.user = undefined;
req.user = decode;
next();
});
} else {
req.user = undefined;
next();
}
});
I also need to set the expiration time.
How can I do that?

Answer 1

Ref : NodeJs - Retrieve user infor from JWT token?
exports.me = function(req,res){
if (req.headers && req.headers.authorization) {
var authorization = headers.authorization,
decoded;
try {
decoded = jwt.verify(authorization, secret.secretToken);
} catch (e) {
return res.status(401).send('unauthorized');
}
var userId = decoded.id;
// Fetch the user by id
User.findOne({_id: userId}).then(function(user){
// Do something with the user
return res.send(200);
});
}
return res.send(500);
}
Ref: For token expiration / extending it JWT (JSON Web Token) automatic prolongation of expiration
Web applications
A good pattern is to refresh the token before it expires.
Set the token expiration to one week and refresh the token every time the user open the web application and every one hour. If a user doesn't open the application for more than a week, they will have to login again and this is acceptable web application UX.
To refresh the token your API needs a new endpoint that receives a valid, not expired JWT and returns the same signed JWT with the new expiration field. Then the web application will store the token somewhere

Answer 2

Modify Your code as follow:-
exports.signin = function (req, res) {
User.findOne({
username: req.body.username
}, function (err, user) {
if (err) throw err;
if (!user || !user.comparePassword(req.body.password)) {
return res.status(401).json({ message: 'Authentication failed. Invalid user or password.' });
}
let NumberOfDayInMiliSec = 1000 * 60 * 60 * 24 * 1 //One Day
return res.json({ token: jwt.sign({ exp: Date.now() + NumberOfDayInMiliSec, email: user.email, username: user.username, _id: user._id }, 'RESTFULAPIs') });
});
};
app.use(function (req, res, next) {
if (req.headers && req.headers.authorization && req.headers.authorization.split(' ')[0] === 'JWT') {
jsonwebtoken.verify(req.headers.authorization.split(' ')[1], 'RESTFULAPIs', function (err, decode) {
if (err) req.user = undefined;
if (decode.exp < Date.now()) {
return res.status(400).json({ status: false, msg: "Token expired" });
}
req.user = decode;
next();
});
} else {
req.user = undefined;
next();
}
});