How to pass extra data and check if token is valid with JWT - node.js

Question

I just started a project where I have to use Node + few things related to it and I feel a little confused!
I use JWT for authentication, particularly I created my project like this:
api
|---teams
|----teams.controller.js
|----teams.router.js
|----teams.service.js
|---users (same as team)
auth
|---token_validation.js
other things
|---other things
I use token_validation.js for JWT to validate user while login and seems it work (verified with Postman)
const jwt = require("jsonwebtoken");
module.exports = {
checkToken: (req, res, next) => {
let token = req.get("authorization");
if (token) {
// Remove Bearer from string
token = token.slice(7);
jwt.verify(token, process.env.JWT_KEY, (err, decoded) => {
if (err) {
console.log("err: " + err);
return res.json({
success: 0,
message: "Invalid Token..."
});
} else {
req.decoded = decoded;
next();
}
});
} else {
// other code
}
}
};
I need to insert a new team in DB (MariaDB) and user can create a new team after login. My problem is that while using Session in Java for e.g. I can easly set extras like username of the logged in user and when I need to know what's the username of the logged in user is, I can take it from session
String username = (String) session.getAttribute("username");
I can't understand how to do the same with Node/JWT. What I need to do is, after login I need to save the user_id and when user crate a new team I need to send to DB the user_id with other data (if token still valid).
const {
create
} = require("./teams.service");
module.exports = {
createTeam: (req, res) => {
const body = req.body;
// here I need to check if token still valid
// if yes -> take user id and send it to DB with
// other data
create(body, (err, results) => {
if (err) { // if fails
// handle
}
return res.status(200).json({ // success
success: 1,
data: results
});
});
},
}
I thought I could add it in user.controller.js when user login:
if (result) {
results.password = undefined;
const jsontoken = sign({ result: results }, process.env.JWT_KEY, {
expiresIn: "1h",
user_id: get somehow //error
});
// other code
}
but it gives me an error, tells me like I can't add user_id to sign. Can anyone please tell me the right way to store and get this kind of data and use them when needed while user still have a valid token to stay logged in?

Answer 1

You are adding your data to the options, not the payload.
if (result) {
results.password = undefined;
results.user_id = XXXXXXXX //get somehow
const jsontoken = sign({ result: results }, process.env.JWT_KEY, {
expiresIn: "1h"
});
...
}

Answer 2

Best option is to set it in localStorage. When you make a req to backend send it with headers, then in backend check if token is valid and send response with data that you want.