Using Ngrx Effects Lifecycle hooks OnInitEffects (seems to emit infinitely)

Question

I'm trying to learn a bit about effect lifecycle hooks introduced in Ngrx 7 and I'm not really understanding something that's happening. I've got an Angular app and I have the following in an effects class, however, the init$ observable is emitting values infinitely. I would have expected it to fire once and complete. I am somewhat new to observables as well. The documentation doesn't really help me out as there aren't really many examples. I could add a take(1), but I would like to understand why it continues to emit forever.

@Injectable()
export class AuthEffects implements OnInitEffects{

  constructor(private actions$: Actions) {}

  @Effect({dispatch: false})
  login$ = this.actions$.pipe(
    ofType<LoginAction>(AuthActionTypes.LoginAction),
    tap(console.log)
  );

  @Effect({dispatch: false})
  logout$ = this.actions$.pipe(
    ofType<LogoutAction>(AuthActionTypes.LogoutAction),
    tap(console.log)
  );

  @Effect()
  init$ = this.actions$.pipe(
    ofType<Action>('[Auth] Effects Init'),
    tap(console.log)
  );

  ngrxOnInitEffects(): Action {
    console.log('AuthEffects init\'d');
    return { type: '[Auth] Effects Init'};
  }
}

Answer 1

This is the expected behaviour - effects' primary usage is to act on some third party side effects. And you set ofType<Action> so it emits whenever any Action happens, while for ex:

  @Effect({dispatch: false})
  login$ = this.actions$.pipe(
    ofType<LoginAction>(AuthActionTypes.LoginAction),
    tap(console.log)
  );

emits whenever LoginAction happens.