Spring Cloud Gateway with Keycloak Integration using OAuth2 OpenId Connect (OIDC)

In this project I am integrating Keycloak with spring cloud gateway as a client using Oauth2 OpenId Connect (OIDC).

We create a realm in keycloak containing a client and set of users. We then integrate the client configuration in our spring cloud gateway application and then authenticate using OpenId Connect.

You can read about this in detail on how to integrate Keycloak with Spring Cloud Gateway on my website RefactorFirst.com

Details Useful for debugging OAuth2 flow

1. To debug issues, you can set the logging to debug using these settings

logging:
    level:
      org:
        springframework:
          security: DEBUG

2. You can find the list of common OAuth2 providers like Okta, Google, etc in this class.

   org.springframework.security.config.oauth2.client.CommonOAuth2Provider
   

3. You can find the start of the configuration from this class for all client registrations.

org.springframework.boot.autoconfigure.security.oauth2.client.OAuth2ClientPropertiesRegistrationAdapter#getClientRegistrations

4. Your OAuth2 client properties are found in this class

org.springframework.boot.autoconfigure.security.oauth2.client.OAuth2ClientProperties

5. The place where it stores incoming resource request to serve once the authentication is successful is in this class

org.springframework.security.web.server.savedrequest.WebSessionServerRequestCache.saveRequest

Export Keyclock Config.

docker exec -it 22dadc3be0dd  /opt/keycloak/bin/kc.sh export --dir /tmp/ --users realm_file --realm My-Realm

Clients can trigger login with url :

oauth2/authorization/keycloak-spring-gateway-client