HTML5的TCP和UDP Web Socket API草案定稿

http://ourjs.com/detail/54810f3e0dad0fbb6d000012

分类 技术前沿   关键字 Html5   发布 kris  2014-12-05 
注意 转载须保留原文链接，译文链接，作者译者等信息。  

这是在Web上实现UDP/TCP API的草案，沿未形成标准。该标准的一大亮点就是使用内置Promise设计模式，替代了传统JavaScript中的事件触发回调。不过各大浏览器厂商会不会这样实现还要打一个问号，毕竟编写标准的学院派和实现标准的行业派很难达到完全统一。

以下内容来自： http://www.w3.org/TR/2014/WD-tcp-udp-sockets-20141202/

接口标准提供对原始UDP套接字(Socket)，TCP客户端套接字和TCP服务器套接字API的定义。

简介

这部分沿未形成规范。您可以使用该API来发送和接收数据，并使用TCP或UDP网络。

使用此API的部分用例：

• 能够与SMTP, POP3 和 IMAP 服务器进行通信的邮件服务器。
• 一个能与IRC服务器进行通信的IRC客户端 （注* IRC是一种通过网络的即时聊天方式。其主要用于群组聊天。）
• 实现一个SSH应用程序
• 与现有的消费硬件产品进行通信，如互联网电视
• 游戏服务器
• 端到端应用程序（注* P2P或对等网络应用）
• 本地网络多播服务（multicast service）发掘，例如UPnP/ SSDP和mDNS

一个UDP的例子：

// // This example shows a simple implementation of UPnP-SSDP M-SEARCH// discovery using a multicast UDPSocket //      var address = '239.255.255.250',    port = '1900',    serviceType = 'upnp:rootdevice',    rn = '\r\n',    search = '';//  Create a new UDP client socketvar mySocket = new UDPSocket();// Build an SSDP M-SEARCH multicast messagesearch += 'M-SEARCH * HTTP/1.1' + rn;search += 'ST: ' + serviceType + rn;search += 'MAN: "ssdp:discover"' + rn;search += 'HOST: ' + address + ':' + port + rn;search += 'MX: 10';// Receive and log SSDP M-SEARCH response messagesfunction receiveMSearchResponses() {           // While data in buffer, read and log UDP message  while (mySocket.readable.state === "readable") {                var msg = mySocket.readable.read();    console.log ('Remote address: ' + msg.remoteAddress +                  ' Remote port: ' + msg.remotePort +                  'Message: ' + ab2str(msg.data));       // ArrayBuffer to string conversion could also be done by piping       // through a transform stream. To be updated when the Streams API      // specification has been stabilized on this point.   }          // Wait for SSDP M-SEARCH responses to arrive       mySocket.readable.wait().then(    receiveMSearchResponses,              e => console.error("Receiving error: ", e);  );     }// Join SSDP multicast groupmySocket.joinMulticast(address);// Send SSDP M-SEARCH multicast messagemySocket.writeable.write(  {data : str2ab(search),   remoteAddress : address,   remotePort : port  }).then(    () => {      // Data sent sucessfully, wait for response      console.log('M-SEARCH Sent');      receiveMSearchResponses();    },    e => console.error("Sending error: ", e););// Log result of UDP socket setup. mySocket.opened.then(  () => {    console.log("UDP socket created sucessfully");  },  e =>console.error("UDP socket setup failed due to error: ", e););// Handle UDP socket closed, either as a result of the application // calling mySocket.close() or an error causing the socket to be    closed.mySocket.closed.then(  () => {     console.log("Socket has been cleanly closed");  },  e => console.error("Socket closed due to error: ", e););

相比UDP，TCP的示例代码显得简单一些

// // This example shows a simple TCP echo client. // The client will send "Hello World" to the server on port 6789 and log // what has been received from the server.//   //  Create a new TCP client socket and connect to remote host     var mySocket = new TCPSocket("127.0.0.1", 6789);// Send data to servermySocket.writeable.write("Hello World").then(    () => {                // Data sent sucessfully, wait for response        console.log("Data has been sent to server");        mySocket.readable.wait().then(            () => {                            // Data in buffer, read it                console.log("Data received from server:" + mySocket.readable.read());                // Close the TCP connection                mySocket.close();            },                         e => console.error("Receiving error: ", e);        );    },    e => console.error("Sending error: ", e););// Signal that we won't be writing any more and can close the write half of the connection.mySocket.halfClose();// Log result of TCP connection attempt. mySocket.opened.then(  () => {    console.log("TCP connection established sucessfully");  },  e =>console.error("TCP connection setup failed due to error: ", e););// Handle TCP connection closed, either as a result of the application // calling mySocket.close() or the other side closed the TCP  // connection or an error causing the TCP connection to be closed.mySocket.closed.then(  () => {     console.log("TCP socket has been cleanly closed");  },  e => console.error("TCP socket closed due to error: ", e););

有什么问题可在Github上面给他们开Issues:， 不过关注者廖廖（14个star目前）： https://github.com/sysapps/tcp-udp-sockets/issues