Angular2 ( 2.2.1 ) Http post request progress bar

Question

How could I get the progress of a file uploading with Angular2 / Http ?
Here I have a service that uploads a file to AWS S3 using pre signed url. Question is, how do I get the status of that upload ?

import { Injectable }                from '@angular/core';
import { Http }                      from '@angular/http';

@Injectable()

export class UploadService {

  constructor ( private http: Http ){}

  upload(url, file){


    var formData = new FormData();
    formData.append('file', file);

    this.http.post(url, formData).subscribe(
      res => console.log( res )
    );
}

Many thanks !