Rails + Dragonfly gem: Saving image in a directory structure based on ActiveRecord object attributes

Question

I'm using dragonfly gem to manage images and attachments in my rails app and I need to store images in a specific directory structure based on my user model. let' say I have user model which has a name and each user has many albums, which have a name also, then I want the images to be stored in "#{RAILS_ROOT}/public/system/#{user.name}/#{user.album.name}/#{suffix}"

I've managed to changed the root_path in dragon fly and I even overrided relative_storage_path like this:

class MyDataStore < Dragonfly::DataStorage::FileDataStore
  private
   def relative_storage_path(suffix)
    "#{suffix}"
   end
end

but still, I don't know how I can pass the ActiveRecord object attributes like user.name and user.album.name to relative_storage_path to create my ideal path.

do you have any idea how I can do such a thing?

Answer 1

Mark Evans the gem author did me a favor and answered this question on google group. Here is his answer that worked pretty well for my case:

Hi there

You can't do this out of the box, because the data store is purposefully designed to be very simple - you pass in data, it gives you back a uid, etc.

If you want to do it you'll have to monkey-patch Attachment#save! like so:

class Dragonfly::ActiveRecordExtensions::Attachment
  def save!
    destroy! if uid_changed?
    self.uid = app.datastore.store(temp_object, parent_model) if has_data_to_store?
  end
end

The only thing I've changed above is that datastore.store takes two args now.

You'll then have to modify/monkey-patch Dragonfly::DataStorage::FileDataStore#store to take into account the second arg.

Out of interest, why do you want the images to be stored in that format?

Cheers Mark