ssdp discovery with node.js

ssdp-discovery.js

// original: https://gist.github.com/chrishulbert/895382

var dgram = require('dgram'); // dgram is UDP

var matcher = process.argv[2] ? new RegExp(process.argv[2]) : undefined;

function search() {
  var client = dgram.createSocket("udp4");
  client.bind();
  client.once('listening', function() {
    var message = new Buffer(
      "M-SEARCH * HTTP/1.1\r\n" +
      "HOST:239.255.255.250:1900\r\n" +
      "MAN:\"ssdp:discover\"\r\n" +
      "ST:ssdp:all\r\n" + // Essential, used by the client to specify what they want to discover, eg 'ST:ge:fridge'
      "MX:2\r\n" + // 2 seconds to respond (but they all respond immediately?)
      "\r\n"
    );

  client.send(message, 0, message.length, 1900, "239.255.255.250", function(err) {
    if (err) throw err;
    console.log('message was sent');
  });
});

client.on('message', function(msg, rinfo) {
    if (!matcher || matcher.test(msg)) {
      console.log("client got: " + msg + " from " + rinfo.address + ":" + rinfo.port);
    }
  });
}

search();