Question

My problem is that when I destroy some carrierwaved model:

Attachment.rb

mount_uploader :attachment, AttachmentUploader

I remove it from the database and serialize it to another table with revisions.

When the user reify the deleted attachment, I need to insert the row back but skipping specific carrierwave callbacks (skip the mount uploder I guess).

The code bellow can do that, but unfortunately it removes all the callbacks from the model and I need them. So I have to skip carrierwave uploader only, otherwise it throws exception with “invalid attachment” when create.

  model.class.skip_callbacks do 
    model.save
  end

It’s possible to do? Thanks!

Answer 1

You can skip specific callbacks using skip_callback, specified with a lambda. Combine that with the specific callback you are trying to avoid and you should be able to achieve the control you are looking for.

class Attachment
  mount_uploader :attachment, AttachmentUploader

  skip_callback :save, :after, :store_attachment!, if: :skip_storage?

  private

  def skip_storage?
    # some skipping logic
  end
end