title: Upload file upload using angular8 and springboot
body: <p>I don't understand the below code</p>
  <pre><code>const req = new HttpRequest('POST', '/upload/file', file, {
    reportProgress: true
  });
  </code></pre>
  <p>I need clarity on the second argument which is a URL, at the moment I do not understand how it is supposed to map to server. I do realize that the above code doesn't use http, and. That's where I get lost. Please explain how server will see this request without URL.</p>