What is the best way to update the accessToken in the app with the new accessToken?

##Before getting to the actual question
Alright I have created my own authentication system that I am going to use on my API.

Simple explanation:

On /signup the user types in username, password etc… the API grants the user with tokens which are stored in the user document in the database. The API also returns with a response body with the new refreshToken and accessToken, my thought here is so the app easily can store the tokens on the phone for later calls to the API.

/login is pretty much the same thing except you only provide username and password.

One of the routes in the API is the /article which you can GET & POST.

Now if you try to for example GET the /article and your accessToken is expired the API will automatically call /token which requires the refreshToken in the header, the /token will then grant you a new accessToken and request the same route you were trying to get (in this case /article) with the new accessToken in the header.

The question:
What is the best way to update the accessToken in the app with the new accessToken?


This is how I do it now, AuthenticateController.authenticate authenticates the accessToken and checks if it is expired and all that then calls next().

The NewsController.getAllArticles gets all the articles and also calls next() so the AuthenticateController.sendAuthorize can run and return the new accessToken in the response header when a new one is granted (I thought this would make it easier to obatin the new token in the app). This is where my question comes in because I can’t call next() on every route because on some routes the main function already returns a response and that means that next() cannot be called which means AuthenticateController.sendAuthorize will never run. I want the AuthenticateController.authenticate to be the only middleware required to authenticate the user.

Peter Kazazes told me this on stackoverflow which worked out:

Instead of waiting until the last route to send the new token, you should move the sendAuthorize middleware above the route’s main response (or combine it with authenticate), and instead send a 401 Unauthorized response with the new token. Then, update the token on the client and resend the request.

It seems like a silly practice to send a valid response with an invalid accessToken anyway. You’re going to want to invalidate tokens eventually (I.e on log out or password change), and you don’t want users to be able to make unauthenticated requests.