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@ciaranj
Created February 17, 2014 18:32
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A *working* (on Windows) UDP Multicast client & server with Node.Js v0.10.25 (I spent a *LOT* of time getting EINVAL and I still don't quite know why :/)
For my own sanity ;) Scraped from a variety of places, including: http://stackoverflow.com/questions/14130560/nodejs-udp-multicast-how-to?utm_medium=twitter&utm_source=twitterfeed
!Server
var news = [
"Borussia Dortmund wins German championship",
"Tornado warning for the Bay Area",
"More rain for the weekend",
"Android tablets take over the world",
"iPad2 sold out",
"Nation's rappers down to last two samples"
];
var dgram = require('dgram');
var server = dgram.createSocket("udp4");
server.bind( function() {
server.setBroadcast(true)
server.setMulticastTTL(128);
setInterval(broadcastNew, 3000);
});
function broadcastNew() {
var message = new Buffer(news[Math.floor(Math.random()*news.length)]);
server.send(message, 0, message.length, 5007, "224.1.1.1");
console.log("Sent " + message + " to the wire...");
}
!Client
var PORT = 5007 ;
var dgram = require('dgram');
var client = dgram.createSocket('udp4');
client.on('listening', function () {
var address = client.address();
console.log('UDP Client listening on ' + address.address + ":" + address.port);
client.setBroadcast(true)
client.setMulticastTTL(128);
client.addMembership('224.1.1.1');
});
client.on('message', function (message, remote) {
console.log('A: Epic Command Received. Preparing Relay.');
console.log('B: From: ' + remote.address + ':' + remote.port +' - ' + message);
});
client.bind(PORT);
@jsammarco
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Thank you for this but how can the client send data back to the server?

@dirkk0
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dirkk0 commented Dec 5, 2022

still works right out of the box! Thank you!

The only things I changed was

  • var client = dgram.createSocket({ type: 'udp4', reuseAddr: true }) in the client and
  • var message = new Buffer.from(news[Math.floor(Math.random() * news.length)]) in the server.

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