I'm using HTTPInterceptor feature in Angular 5.
It is working as expected while cloning http-request and sending to server(back-end server).
I am showing and hiding application loader from HTTPInterceptor only and this also working fine but i have used polling on one GET request, which fetches data from back-end server in every 5 seconds which makes users irritating. 
So, Is there any way to check specific request in HTTPInterceptor? and also do not allow to show/hide loader on that request.

Following is the current code snippet of intercept function:

```js
  intercept (req: HttpRequest<any>, next: HttpHandler): Observable<HttpEvent<any>> {
    this.loadingIndicatorService.showLoader();
    this.customAuthorizationHeader();
    const apiRequest = req.clone({headers:this.headers});
    return next.handle(apiRequest).do
    ((response) => {
        if (response instanceof HttpResponse) {
          this.loadingIndicatorService.hideLoader();
        }
      },
      (error) => {
        this.loadingIndicatorService.hideLoader();
      });
  };
```

Thanks in advance.