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c#jsonangularrestclient

Angular 8 - Why client makes multiple API calls to back-end

I have a classic client application with API calls to the server to make operations on DB. But for some reason, every client method in service makes two calls to my controller when I need just once.

What's the reason, why and how I could fix it? Moreover, the second call comes also if the back-end didn't return anything yet but still performing operation.

That's some code example:

Method calls the service:

export class TestingComponent implements OnInit {

results: any;

constructor(
private testingservice: TestingService) { }

ngOnInit() {
let test = true;
this.startingMethod(test);
 }

startingMethod(test) {
    this.testingservice.getData(test).subscribe( data => {
        this.results = data;
  })};
}

Service method:

export class TestingService{

constructor(private configService: ConfigService, private http: HttpClient) { }

getData(test: boolean): Observable<any> {

let urlc = this.configService.getCurrentEndpoints();
let params = new HttpParams();
params = params.set('test', test);
return this.http.get<any>(`${urlc.baseUrl}${urlc.getdata}`, {'params': params });
}
}

I hope was clear enough, but if I don't freely ask me more details. Thanks a lot!

Solution

  • Seems like it's a bug from the browsers, they sends the second request to get the favicon of the page, and since they don't have it, it just brings anything.

    This is a link for the Chrome bug. https://bugs.chromium.org/p/chromium/issues/detail?id=39402

    Firefox, and most other browsers, also send out a request for a favicon when they first connect, but cache the result i.e. if there isn't a favicon returned first time, they don't keep trying - which is why you're only seeing a single request from Firefox. It seems Chrome is unfortunately a little too persistent with its favicon requestiness.