How to return value after redirect?

Question

Node.js

You need to add social login. networks through the AOouth token. But, after the user accepts access rights for the application, there is a redirect to the page specified during application registration. Therefore, it will not work to get a token through a regular request. How to get around this and send the logged in user's token to the client?
The web application is written in react, so I send the login request from the react component and all routing is written on the client.