Passing jwt token/userid from `app.post()` to the `app.get()` route - node.js

Question

This is my app.post()which gets form data from client.
app.post('/api/login', async (req, res) => {
const { emailid, password } = req.body
const user = await User.findOne({ emailid }).lean()
if (!user) {
return res.json({ status: 'error', error: " Invalid username/Password" })
}
if (bcrypt.compare(password, user.password)) {
const token = jwt.sign({ id: user._id, emailid: user.emailid }, 'secret', { expiresIn: '24h' })
return res.json({ status: 'ok', data: token, user_id: user._id })
}
res.json({ status: 'error', error: " Invalid username/Password" })
})
I need to pass the jwt token or the user_id to my
app.get('/', (req,res)=>{
res.render('index')
})

Answer 1

For this, you will need to create an authentication middleware that will check your request headers for a jwt token, which you can then decode to get the user_id or any other data that you passed to it during encryption. A sample middleware can look like the one below
const isAuth = (req) => {
const authorization = req.headers["authorization"];
if (!authorization) throw new Error("You need to log in");
const token = authorization.split(" ")[1];
const { user_id} = verify(token, process.env.ACCESS_TOKEN_SECRET);
return {user_id, token};
};
After you setup your authorization middleware, you can then go ahead and use it in your routes like so
app.get('/', (req,res)=>{
const {token, user_id) = isAuth(req);
//use token and user_id here or throw error if not available in case this is a protected route
res.render('index')
})