# File lib/paperclip/storage/s3.rb, line 168
      def s3_interface
        @s3_interface ||= begin
          config = { :s3_endpoint => s3_host_name }

          if using_http_proxy?

            proxy_opts = { :host => http_proxy_host }
            proxy_opts[:port] = http_proxy_port if http_proxy_port
            if http_proxy_user
              userinfo = http_proxy_user.to_s
              userinfo += ":#{http_proxy_password}" if http_proxy_password
              proxy_opts[:userinfo] = userinfo
            end
            config[:proxy_uri] = URI::HTTP.build(proxy_opts)
          end

          [:access_key_id, :secret_access_key].each do |opt|
            config[opt] = s3_credentials[opt] if s3_credentials[opt]
          end

          AWS::S3.new(config.merge(@s3_options))
        end
      end