Rails Fog create a file based on a remote link

Question

I have Rails application and use fog gem to upload files to cloud storage (Rackspace). As of now I have been successfully uploading local files to cloud storage.

@service = Fog::Storage.new(options)
directory = @service.directories.new :key => 'test'
directory.files.create :key => path, :body => file, :content_type => content_type

I have a new requirement now. I want to be able to use remote link (public-url) and have it uploaded to cloud storage. Is there a way to achieve this without downloading it locally or loading the whole thing in memory?

I'm looking for something like this:

directory.files.create :key => path, :body => 'url-to-remote-file', :content_type => content_type

A stream-based approach would also be quite helpful.

Thanks.