title: rest-framework @detail_route without pk
body: <p>In rest framework exists some way to use session user instead pk and <code>self.get_object()</code> in a <code>@detail_route</code> view?</p>
  
  <p>I want to use <code>request.user</code> and don't send pk in the url.</p>
  
  <p>Or maybe use another decorator instead <code>@detail_route</code>...</p>