Validating asymmetric signed JWT token

In the previous recipe, you learned how to generate JWT access tokens at the Authorization Server side using asymmetric keys. Now it's time to know how to validate any given JWT access token asymmetrically signed at the Resource Server side. Now instead of statically setting up the key to validate the access token, the Resource Server will retrieve the public key through the /oauth2/token_key endpoint provided by the Authorization Server. It gives flexibility to the OAuth Provider and helps with maintainability.

Getting ready

To run this recipe, you will need to create a Spring Boot project for the Resource Server using Java 8, Maven, Spring Web, and Spring Security. Some dependencies will be presented in theHow to do it... section.

How to do it...

This recipe shows you how to create the Resource Server which will be defined as the project jwt-asymmetric-resource. This project is available on GitHub in the Chapter05 folder and all that you need to create...