JWT - Retrieving Token - mongodb

Question

I am trying to figure out how do I get the token id or a new token for an existing user using JWT. The goal is to take email and password, find it in the mongo DB, and then send back to the client the token, then store the token for the session.
Currently when registering I encrypt the password and store the email, name, and password in a mongoDB.
Based on what I have been learning, the actual token is not stored in the mongoDB, but the token is generated from the _id, which I cant pull for some reason to just resign and get the token back but no luck. Any advice is greatly appreciated its for a personal project.
User.create({
name : req.body.name,
email : req.body.email,
password : req.body.password,
},
function (err, user) {
if (err) return res.status(500).send("There was a problem registering the user.")
// create a token
var token = jwt.sign({ id: user._id }, config.secret);
res.status(200).send({ auth: true, token: token });
});

Answer 1

You can try user._id.toString() or user.id instead of user._id to retrieve the user id.
You may get some idea from the code below how you can use JWT token for verification purpose.
login: (req, res) => {
const { name, password } = req.body;
mongoose.connect(connUri, { useNewUrlParser: true }, (err) => {
let result = {};
let status = 200;
if(!err) {
User.findOne({name}, (err, user) => {
if (!err && user) {
// We could compare passwords in our model instead of below as well
bcrypt.compare(password, user.password).then(match => {
if (match) {
status = 200;
// Create a token
const payload = { user: user.name };
const options = { expiresIn: '2d', issuer: 'anshukumar.me' };
const secret = process.env.JWT_SECRET;
const token = jwt.sign(payload, secret, options);
// console.log('TOKEN', token);
result.token = token;
result.status = status;
result.result = user;
} else {
status = 401;
result.status = status;
result.error = `Authentication error`;
}
res.status(status).send(result);
}).catch(err => {
status = 500;
result.status = status;
result.error = err;
res.status(status).send(result);
});
} else {
status = 404;
result.status = status;
result.error = err;
res.status(status).send(result);
}
});
} else {
status = 500;
result.status = status;
result.error = err;
res.status(status).send(result);
}
});
}
You can also check this GitHub repo which has implemented JWT Token in Node JS.
https://github.com/kumaranshu72/JWT-nodeJS
You may also follow the following tutorial to get a good idea of how to implement JWT authentication : https://scotch.io/tutorials/authenticate-a-node-es6-api-with-json-web-tokens

Answer 2

I think you can access the id without _
User.create({
name : req.body.name,
email : req.body.email,
password : req.body.password,
},
function (err, user) {
if (err) return res.status(500).send("There was a problem registering the user.")
// create a token
var token = jwt.sign({ id: user.id }, config.secret);
res.status(200).send({ auth: true, token: token });
});
user.id instead of user._id