class Roadie::NetHttpProvider

def download(url)
  url = "https:#{url}" if url.start_with?("//")
  uri = URI.parse(url)
  if access_granted_to?(uri.host)
    get_response(uri)
  else
    raise CssNotFound.new(url, "#{uri.host} is not part of whitelist!", self)
  end
end