End Observable interval when route changes in Angular

Question

I start a interval in an Angular component, but it keeps making requests even after I change the route. How can I stop the interval?

//returns an observable
getAllPolls() {
    return Observable.interval(2000).switchMap(() => this._http.get('https://xq4kftam4k.execute-api.us-east-1.amazonaws.com/test/polls2'))
        .map((res: Response) => res.json())

}

Answer 1

You should save subscription to observable:

this.subscription = getAllPolls().subscribe(...);

And implement OnDestroy interface:

  ngOnDestroy() {
     this.subscription.unsubscribe();
  }