node-kcp/test/udpserver.js

var kcp = require('./../build/Release/kcp');
var dgram = require('dgram');
var server = dgram.createSocket('udp4');
var clients = {};
var interval = 200;

var output = function(data, size, context) {
    server.send(data, 0, size, context.port, context.address);
};

server.on('error', (err) => {
    console.log(`server error:\n${err.stack}`);
    server.close();
});

server.on('message', (data, rinfo) => {
    var k = rinfo.address+'_'+rinfo.port;
    if (undefined === clients[k]) {
        var context = {
            address : rinfo.address,
            port : rinfo.port
        };
        var kcpobj = new kcp.KCP(123, context);
        kcpobj.stream(1);
        kcpobj.nodelay(0, interval, 0, 0);
        kcpobj.output(output);
        clients[k] = kcpobj;
    }
    var kcpobj = clients[k];
    kcpobj.input(data);
    var recv = kcpobj.recv();
    if (recv) {
        recv = recv.toString();
    	console.log(`Server recv ${recv} from ${kcpobj.context().address}:${kcpobj.context().port}`);
    	kcpobj.send('RE-'+recv);
    }
});

server.on('listening', () => {
    var address = server.address();
    console.log(`server listening ${address.address} : ${address.port}`);
    setInterval(() => {
        for (var k in clients) {
            var kcpobj = clients[k];
        	kcpobj.update(Date.now());
       	}
    }, interval);
});

server.bind(41234);