node.js - node-formidable 和一个简单的进度条

Question

如果我查看 node-formidable 文档，我可以阅读:

"Event: 'progress' (bytesReceived, bytesExpected)
Emitted after each incoming chunk of data that has been parsed. 
Can be used to roll your    own progress bar."

我想知道如何实现我自己的进度条我的意思是如何读取客户端的信息？我很困惑。它是通过在 POST 启动后启动的轮询 GET 实现的，还是可以在上传时从 POST 请求中读取信息？

如果我看这个:

http.createServer(function(req, res) {
  if (req.url == '/upload' && req.method.toLowerCase() == 'post') {
    // parse a file upload
    var form = new formidable.IncomingForm();
    form.parse(req, function(err, fields, files) {
      res.writeHead(200, {'content-type': 'text/plain'});
      res.write('received upload:\n\n');
      res.end(sys.inspect({fields: fields, files: files}));
    });
    return;
  }

看起来/upload url 正在处理 POST 请求并返回一些东西 res.write('received upload:\n\n');

我的问题是谁能读懂

res.write('received upload:\n\n');

Answer 1

您不需要覆盖 onPart Hook !

只需在每个表单 progress 事件回调调用时通过套接字广播一条消息，如下所示:

form.on('progress', function(bytesReceived, bytesExpected) {
  var progress = {
    type: 'progress',
    bytesReceived: bytesReceived,
    bytesExpected: bytesExpected
  };

  socket.broadcast(JSON.stringify(progress));
});

而不是在客户端监听套接字消息。