# File lib/rubygems/mirror/fetcher.rb, line 14
  def fetch(uri, path)
    modified_time = File.exists?(path) && File.stat(path).mtime.rfc822

    req = Net::HTTP::Get.new URI.parse(uri).path
    req.add_field 'If-Modified-Since', modified_time if modified_time

    @http.request URI(uri), req do |resp|
      return handle_response(resp, path)
    end
  end