CarrierWave uploader with CarrierWaveDirect included not generating correct key on non-direct uploads

Question

I am using rails, and have an image uploader that inherits from CarrierWave::Uploader::Base but includes CarrierWaveDirect::Uploader. We are using Fog as storage and AWS S3 as the provider. We use it for both direct and indirect uploads.

I have just bumped our CarrierWaveDirect gem above 0.0.16 and I see that in this version there was a change to the key method in the Uploader. It went from using the url to using the dynamically generated "#{mounted_as}_identifier" method to create the key:

0.0.15 functionality:

    def key
      return @key if @key.present?
      if present?
        self.key = URI.parse(URI.encode(url, " []+()")).path[1 .. -1] # explicitly set key
      else
        @key = "#{store_dir}/#{guid}/#{FILENAME_WILDCARD}"
      end
      @key
    end

0.0.16 functionality:

    def key
      return @key if @key.present?
      if present?
        identifier = model.send("#{mounted_as}_identifier")
        self.key = [store_dir, identifier].join("/")
      else
        guid = SecureRandom.uuid
        @key = [store_dir, guid, FILENAME_WILDCARD].join("/")
      end
      @key
    end

Since this change when we are uploading non-directly (file uploaded in the browser, assigned to model in question then saved) the uploader is unable to generate the correct identifier. The present? check returns true, I presume because there is a cached file assigned, but calling "#{mounted_as}_identifier" on the model returns nil, because it hasn't written the key to the column yet.

When I don't include CarrierWaveDirect::Uploader, or if I use version 0.0.15, all works as expected. However, using them together means that non-direct uploads go to just '/uploads/uploads', and rewrite the same location with each upload.

Does anyone know if this is just a quirk of using both uploaders together, or if it's something we're doing wrong, or if it's a bug with the gem?

Any thoughts much appreciated.