alxhub

abstract class AuthService {
  // Subject tracks the current token, or is null if no token is currently
  // available (e.g. refresh pending).
  private subject = new BehaviorSubject<string|null>(null);

  readonly refreshToken: Observable<any>;
  readonly token: Observable<string>;

  constructor() {
    // refreshToken, when subscribed, gets the new token from the backend,