Do I have to unsubscribe from completed observable in rxjs?

Question

If an observable completes, do I still have to unsubscribe / dispose (in RxJS) the observable to remove the Observer (prevent memory leaks) or is this handled internally by Rxjs once a onComplete or onError event occurs?

Answer 1

No, you don't need to unsubscribe from an observable you know has completed.

If you look at the source code of the RxJS toPromise() function, you'll see a subscribe, but no unsubscribe. That's because it is not necessary, you know the observable is completed.