Full-Stack React Projects - Second Edition

Saving credentials

In order to save the JWT credentials that are received from the server on successful sign-in, we use the authenticate method, which is defined as follows.

mern-skeleton/client/auth/auth-helper.js:

authenticate(jwt, cb) {    if(typeof window !== "undefined")        sessionStorage.setItem('jwt', JSON.stringify(jwt))    cb()}

The authenticate method takes the JWT credentials, jwt, and a callback function, cb, as arguments. It stores the credentials in sessionStorage after ensuring window is defined, in other words ensuring this code is running in a browser and hence has access to sessionStorage. Then, it executes the callback function that is passed in. This callback will allow the component – in our case, the component where sign-in is ...