paperclip error while reporcessing after rails 3 upgrade

Question

I have paperclip working uploading and saving different styles for images but when i go to crop the image using jcrop from railscasts tutorial it doesnt crop image. I get

Answer 1

Just as an addendum to the accepted answer (assuming you're following Ryan Bates' Railscast), you'll need to remove the following lines from your model:

after_update :reprocess_avatar, :if => :cropping?

def reprocess_avatar
  avatar.reprocess!
end

This will cause an infinite loop. You then just need to move the logic to the update action in the controller by adding something like this:

if @user.cropping?
  @user.avatar.reprocess!
end

I got hung up on this for a while, so thought I'd share.