how to secure routes in API and in client with next-auth - express

Question

I run an backend and a frontend both served by express the backend on port 8080 and the frontend on port 80.
/api/route1 returns 200ok with json
/api/route2 returns 200ok with json
So the app works fine fetching these routes. Now to the thing I need your help with. I have added next-auth so in the frontend I can
const [ session, loading ] = useSession();
to do something like
{!session && <p>You are not logged in</p>}
which works but what I haven't figured out is how to protect the routes to the API. I want to protect route1 and route2 in both frontend and backend. I guess when I'm logged in a need to pass a token down to the API but how can I have these 2 talking to each other
/api/route1 returns 200ok with json
/api/route2 returns 200ok with json
Remember I run the backend and frontend separately because my production build is in docker that's why.

Answer 1

You can find an example of this in the next-auth-example project
// pages/api/examples/protected.js
import { getSession } from 'next-auth/client'
export default async (req, res) => {
const session = await getSession({ req })
if (session) {
res.send({ content: 'This is protected content. You can access this content because you are signed in.' })
} else {
res.send({ error: 'You must be sign in to view the protected content on this page.' })
}
}
If a session object exists (i.e. is not null) then it means they either have a valid session token (if using database sessions) or a valid signed JSON Web Token (if using JWT session).
In both cases the session token is checked to make sure it is valid and has not expired.
The request object req is passed through to getSession() call when used in this way so that the cookie containing the session token can be inspected and validated.

Answer 2

The way that you could handle protected routes within Node is by using middleware.
So lets say that you have a route for adding employees salary in database, so obviously such a route needs someone that is and authenticated admin right?
So you could make a middleware function like the simple one below
const validateAdminCookie = (req, res, next)=>{
//Here you then write all your logic on how you validate admin
//Now you will have conditonals here that:
if (!validatedCookie){
return res.status(400).json({msg:'Not authorized'})
}
next();
}
So now that function is what you will pass within your route so that is gets executed first and when user is valid authenticated admin then the next() will push down that user to the main route that they were trying to hit else if not authenticated then the get back a message that they are not authenticated.
Now how you pass this middleware is like this below:
router.post('/api/admin-update-salaries',validateAdminCookie, (req, res)=>{
//Now that **validateAdminCookie** will execute first and if all
//checks out then user will be pushed down to the main part
//that is this route here
})