React, connect-mongoose & Express session/user login - reactjs

Question

I'm trying to get sessions to work with a React front-end and an express + connect-mongo using MongoStore back-end.
Handle Register Function
async function handleRegister(evt){
//Prevent default form redirect.
evt.preventDefault();
//Create a new user objec to pass into axios
const user = {
username: username,
password: password
}
//Send axios post request to nodeJS API.
await axios.post("http://localhost:5000/users/register",user)
.then((res) => {
history.push({
pathname: '/',
state: res.data
});
})
.catch((err) => {
console.log(err);
});
//Push react history back to index page.
}
Handle Login function
const handleLogin = async (evt) => {
//Prevent default form submission
evt.preventDefault();
const loginDetails = {
username: username,
password: password,
}
//send login request to api
await axios.post('http://localhost:5000/users/login', loginDetails)
.then((res) => {
})
.catch((err) => {
})
}
I'm stuck on trying to figure out how to make the data be sent back to react after either of the above functions. In the register function I've sent back the res.data which contains the session. See blow route for express
router.post('/register', async (req, res) => {
//Destructure req.body.
const {username,password} = req.body;
//hash password.
const hashedPassword = await hashPassword(password);
//Create new user to store in mongodb.
const newUser = {
username: username,
password: hashedPassword
}
//Create new user document
await User.create(newUser, (err, newlyAddedUser) => {
if(err){
console.log(err);
}else{
req.session.username = newlyAddedUser.username;
console.log(req.session);
res.send(req.session);
}
})
});
With the console.log(req.session) it outputs the cookie and the username I added in the session itself.
Should I make a user object on the react side and store the username and password inside?
Should I be passing back the session itself to the route with history.push({ pathname: '/',state: res.data});
How can I verify that the session is valid for the user using connect-mongo?

Answer 1

I spent 10 minutes trying to understand what is your goal. Didn't find.
But whatever you need to use a jsonwebtoken if you want to verify that the session is valid like you said
Enjoy https://jwt.io/
https://www.npmjs.com/package/jsonwebtoken
I wouldn't store the session in the History state API like you do.
history.push({
pathname: '/',
state: res.data
});
You better use a sessionStorage and/or localStorage. The name just talks by itself.
Give me one point please