Response progress percentage in Node.js

index.js

http.createServer(function(request, response) {
  var newFile = fs.createWriteStream('file.txt');
  var fileByes = request.header['content-length'];
  var uploadedBytes = 0;

  request.pipe(newFile);
  request.on('data', function(chunk) {
    uploadedBytes += chunk.length;
    var progress = (uploadedBytes / fileBytes) * 100;
    response.write('progress: ' + parseInt(progress, 10) + '%\n')
  });
});