nodejs实现UDP组播示例

众所周知，UDP数据传输方式有 单播，组播，广播。
其中单播模式是最常用，这里就不再啰嗦了，网上随便都能搜到。

下面的示例主要实现简单的UDP组播方式。可以正常收发UDP数据。

Server端代码

const dgram = require('dgram');
const server = dgram.createSocket('udp4');

// const local_ip = "192.168.0.xx";
const multicast_ip = "225.0.0.100";  // 这里必须是一个组播地址(D类IP地址)

server.on('close', ()=>{
    console.log('close socket');
});

server.on('listening', ()=>{
    console.log('listening...');
    server.setBroadcast(true);
    server.setMulticastTTL(128);
    server.addMembership(multicast_ip);

    setInterval(()=>{
        send_msg();
    }, 2000);
});

server.on('message', (msg, rinfo)=>{
    console.log(`receive client message from ${rinfo.address}: ${rinfo.port}: ${msg}`);
});

server.bind();  // 随机绑定本机一个端口

function send_msg(){
    console.log('send msg');
    server.send('hi, im server...', '8062', multicast_ip);
}

Client端代码:

const dgram = require('dgram');
var client = dgram.createSocket('udp4');

// const local_ip = '192.168.0.xx';
const multicast_ip = "225.0.0.100";   // 这里必须是一个组播地址(D类IP地址)

client.on('close', ()=>{
    console.log('client closed');
});

client.on('error', (err) =>{
    console.log('client error' + err);
});

client.on('listening', ()=>{
    console.log('client listening...');
    client.setBroadcast(true);
    client.setMulticastTTL(128);
    client.addMembership(multicast_ip);
});

client.on('message', (msg, rinfo) => {
    console.log(`receive server message from ${rinfo.address}: ${rinfo.port}: ${msg}`);
});
client.bind('8062');  // 监听组播数据的端口

参考:

• https://www.daozhao.com/8277.html
• https://stackoverflow.com/questions/14130560/nodejs-udp-multicast-how-to