How does the Angular resolver handle subscriptions?

I am using an Angular resolver to load initial Data of my page. As known it is possible to either return an observable or a promise.

In my case I have this:

export class MySiteResolver implements Resolve<ApiResponse> {
readonly #myApiService = inject(MyApiService);

resolve(route: ActivatedRouteSnapshot, state: RouterStateSnapshot): Observable<ApiResponse> {
const param = Number(route.paramMap.get("param"));
return this.#myApiService.getMethod(param);
}
}


As expected when loading the page, the resolver subscribes to the observable and return the Api results.

Now I have two questions:

• Does the resolver keep the subscription alive? or does it take only the first/last result of my api call?
• If the subscription stays alive, does it unsubscribe to it after changing the route?

Or just in general, how does it handle the subscription?

I looked up to figure out an answer, but I couldn't really find anything in the Angular documentations, neither in related questions in stackoverflow. I definitely could take the safe way and either return a promise or use the first() operator. However I insist on figuring out how Angular handles it.

I appreciate any insights. Thank you for your time!

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