Using shareReplay(1) in Angular - still invokes http request?
If you call every time this.http.get(API_ENDPOINT).pipe(shareReplay(1)), each time http request will be triggered. If you want to make http call once and cache data, the following is recommended.
You first get the observable for data:
ngOninit(){ this.data$ = this._jokeService.getData().pipe(shareReplay(1)); }Now subscribe multiple times:
public getData(){ this.data$.subscribe(); }Your service:
public getData() { return this.http.get(API_ENDPOINT) }
In service:
getData$ = this.http.get(API_ENDPOINT).pipe(shareReplay(1));In component, need to unsubscribe and you can subscribe multiple times with single API call:
ngOninit(){ this.data$ = this._jokeService.getData$; this.data$.subscribe() }In template, use:
*ngIf="data$ | async as data"