title: Is it possible to have a dynamic storage path with carrierwave?
body: <p>I am starting with <a href="https://github.com/jnicklas/carrierwave" rel="nofollow">carrierwave</a> for file uploads and have been  quite happy with it so far. My files are stored  on amazon s3 which was fairly easy and it works reliably. </p>
  
  <p>Now I have a model named <code>pictures</code> and an uploader name <code>MainUploader</code>. I need a special dynamic path to save those files to when uploaded.</p>
  
  <p>I am also using devise and I have the <code>current_user</code> I can access from my views and controller but not from the carrierwave uploader. I need the path of the file to be something like</p>
  
  <p><code>uploads/#{current_user.location}/#{current_user.first_name}/images</code></p>
  
  <p>but I cannot access the current_user from the uploader and haven't seen any alternatives. Is this type of dynamic path possible with carrierwave (without re-writing large amounts of this gem)? </p>
  
  <p>Any pointers are greatly appreciated. 
  Thank you for your help.</p>