Obtaining user roles in servlet application using keycloak

Question

I\'m using keycloak to protect my servlet. I have to add new roles and assign them to users dynamically. It works in keycloak using admin API, but I can\'t figure out how to

Answer 1

If the servlet is protected by keyclaok then you can use the following API to get the KeycloakSecurityContext and then access the Set of roles to modify it.

KeycloakPrincipal principal = (KeycloakPrincipal) request.getUserPrincipal();

 principal.getKeycloakSecurityContext().getToken().getRealmAccess().getRoles().add("Test-Role");

A sample servlet request might look like this.

protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    @SuppressWarnings("rawtypes")
    KeycloakPrincipal principal = (KeycloakPrincipal)request.getUserPrincipal();
    if (principal != null) {
        //user has a valid session, we can assign role on the fly like this
        principal.getKeycloakSecurityContext().getToken().getRealmAccess().getRoles().add("Test-Role");

        }
}