Rxjs number of observable subscriptions

Question

In my Angular 2 app i have many observables and subscriptions. Ofcourse I should unsubscribe when I leave the page, but i\'m trying to find out if it\'s possible to get the

Answer 1

Probably a bit late, but you could leverage the help of rxjs-spy.

This solution is equivalent the proposed one, and, in my opinion, better maintainable.

I usually enable it globally in main.ts as a fire and forget strategy. You simply have to:

1. install rxjs-spy via your package manager
2. import in main.ts the reference to the create function: import { create } from 'rxjs-spy';

3. initialize the rxjs-spy in debug builds right after the angular initialization snippet:

   
   if (environment.production) {
       enableProdMode();
   }
   else {
       //we enable RXjs Spy on non production bulds only
       const spy = create();
       // we call show for two purposes: first is to log to the console an empty snapshot so we can see that everything is working as expected, then to suppress unused variable usage (the latter is a convention on mine)
       spy.show();
   }
   
   

4. give your observables a name:

   
   import { tag } from 'rxjs-spy/operators';
   
   ...
   
   // This is a sample method which asks for a "Product" entity. Product and this.http is omitted as the focus is on tagging the observable
   public getProductById(productId: number): Observable {
       let params = new HttpParams()
           .append('productId', productId.toString())
           ;
       // we tag the returned observable with the name 'getProductById' (this is a convention on mine, you can choose whatsoever name)
       return this.http.get(this.baseUrl + "api/product", { params: params }).pipe(tag("getProductById"));
   }
   
   

5. when you need to look at rxjs state, you can simply open the console window and use rxSpy.show() to have the current snapshot

You may use additional commands. A very detailed tutorial is Debugging with rxjs Spy.

(I'd be very glad if somebody reading this answer manages to fix the formatting as I cannot have it properly within the list)