title: HTTP status code 202 or 303. When I need use it?
body: <p>I have <strong>PRIMARY</strong> url in web application which accept by POST request some data.
  This url send this data to <strong><em>INTERNAL</em></strong> url (not accessable by user)
  That <strong><em>INTERNAL</em></strong> url are processing that data for a long time for example 30 min.
  My <strong>PRIMARY</strong> url after post request must redirect to <strong><em>MAIN</em></strong> url. What response HTTP STATUS CODE header I must to send in <strong>PRIMARY</strong> url after posting? <br><br>
  <strong>202</strong>?  - yes, maybe, because it means "The request has been accepted for processing, but the processing has not been completed."<br>
  But I must to redirect back user.. redirects use "3xx" HTTP STATUS CODE. So "<strong>303</strong>" or not?</p>