title: PaperTrail: how to differentiate whodunnit when we track changes by both Users *and* AdminUsers?
body: <p>Our model's <code>whodunnit</code> value is a string - for example <code>"22"</code> as in the <code>User</code> with an <code>id</code> of <code>22</code>.</p>
  
  <p>The problem is we use both the <code>User</code> and <code>AdminUser</code> models to track whodunnit. As such, it is impossible to tell if a change was made by a User or, instead, by an AdminUser:</p>
  
  <pre><code>def user_for_paper_trail
    current_user || current_admin_user
  end
  </code></pre>
  
  <p>I'm a bit new to PaperTrail but worked my way through their docs and couldn't come up with any solutions. It might be a strange request, but I'd love for something like an arbitrary field which we could add a value for as a whodunnit <code>type</code>, if that makes sense. Or a way to only track certain changes depending on the controller (which would work in this case since I'd only track changes which were made via the AdminPanel).</p>
  
  <p>Thanks for any suggestions or guidance.</p>