multipart_body

# File actionpack/lib/action_controller/integration.rb, line 380
        def multipart_body(params, boundary)
          multipart_requestify(params).map do |key, value|
            if value.respond_to?(:original_filename)
              File.open(value.path) do |f|
                f.set_encoding(Encoding::BINARY) if f.respond_to?(:set_encoding)

                "--\#{boundary}\\r\nContent-Disposition: form-data; name=\"\#{key}\"; filename=\"\#{CGI.escape(value.original_filename)}\"\\r\nContent-Type: \#{value.content_type}\\r\nContent-Length: \#{File.stat(value.path).size}\\r\n\\r\n\#{f.read}\\r\n"
              end
            else
"--\#{boundary}\\r\nContent-Disposition: form-data; name=\"\#{key}\"\\r\n\\r\n\#{value}\\r\n"
            end
          end.join("")+"--#{boundary}--\r"
        end