Vaadin 14 and Push: Accessing Spring SecurityContext and Authentication outside the request thread - spring

Question

I had the same problem this guy had:
https://vaadin.com/forum/thread/3383122/17008971
When receiving a status from the server I try to refresh content via push (using ui.access) on the client. That content needs the current principal's information.
final SecurityContext securityContext = SecurityContextHolder.getContext();
final Authentication authentication = securityContext.getAuthentication();
this
authentication
is returning null.
He solved this problem using Vaadin Shared Security, but I can't find any repo or library called Vaadin Shared Sec. Are there any other ways to solve the problem?

Answer 1

Why not just get the auth details in the view constructor and make them class-scoped, or have a bean to do that and set its values ? E.g.
#Route("some-view")
public class SomeView extends VerticalLayout {
Authentication authentication;
private void doHeavyStuff() {
try {
Thread.sleep(1500);
} catch (InterruptedException ex) {
// ignore
}
}
public SomeView() {
authentication = SecurityContextHolder.getContext().getAuthentication();
final Button button = new Button("Click me", e -> {
Notification.show("CLICKED");
getUI().ifPresent(ui -> {
ExecutorService executor = Executors.newSingleThreadExecutor();
executor.submit(() -> {
doHeavyStuff();
ui.access(() -> {
Notification.show("Calculation done");
});
});
});
});
add(button);
// simple link to the logout endpoint provided by Spring Security
Element logoutLink = ElementFactory.createAnchor("logout", "Logout");
getElement().appendChild(logoutLink);
}
}
I based this answer (tested it as well) in this tutorial, if you want to learn more about it:
https://vaadin.com/learn/tutorials/securing-your-app-with-spring-security/speciale