Sometimes, we want to to call finally on subscribing to observable with Rxjs and JavaScript.

In this article, we’ll look at how to to call finally on subscribing to observable with Rxjs and JavaScript.

How to call finally on subscribing to observable with Rxjs and JavaScript?

To to call finally on subscribing to observable with Rxjs and JavaScript, we call pipe on the observable we subscribed to.

For instance, we write

const source = new Observable((observer) => {
  observer.next(1);
  observer.error("error message");
  observer.next(3);
  observer.complete();
}).pipe(publish());

source.pipe(finalize(() => console.log("Finally callback"))).subscribe(
  (value) => console.log(value),
  (error) => console.log(error),
  () => console.log("complete")
);

to create an Observable.

And then we call pipe to emit the data.

Then we call pipe with the observable returned by finalize.

We call finalize with a callback that runs when all the observable code is run.

pipe returns another observable that we call subscribe on to get the data from pipe.

Conclusion

To to call finally on subscribing to observable with Rxjs and JavaScript, we call pipe on the observable we subscribed to.