node-gamedig/lib/index.js

var dgram = require('dgram'),
	EventEmitter = require('events').EventEmitter,
	util = require('util'),
	dns = require('dns'),
	TypeResolver = require('./typeresolver');

var activeQueries = [];

var udpSocket = dgram.createSocket('udp4');
udpSocket.unref();
udpSocket.bind(21943);
udpSocket.on('message', function(buffer, rinfo) {
	if(Gamedig.debug) console.log(rinfo.address+':'+rinfo.port+" <--UDP "+buffer.toString('hex'));
	for(var i = 0; i < activeQueries.length; i++) {
		var query = activeQueries[i];
		if(
			query.options.address != rinfo.address
			&& query.options.altaddress != rinfo.address
		) continue;
		if(query.options.port_query != rinfo.port) continue;
		query._udpResponse(buffer);
		break;
	}
});
udpSocket.on('error', function(e) {
	if(Gamedig.debug) console.log("UDP ERROR: "+e);
});

Gamedig = {

	query: function(options,callback) {
		if(callback) options.callback = callback;

		var query;
		try {
			query = TypeResolver.lookup(options.type);
		} catch(e) {
			process.nextTick(function() {
				callback({error:e.message});
			});
			return;
		}
		query.debug = Gamedig.debug;
		query.udpSocket = udpSocket;
		query.type = options.type;
		
		if(!('port' in query.options) && ('port_query' in query.options)) {
			if(Gamedig.isCommandLine) {
				process.stderr.write(
					"Warning! This game is so old, that we don't know"
					+" what the server's connection port is. We've guessed that"
					+" the query port for "+query.type+" is "+query.options.port_query+"."
					+" If you know the connection port for this type of server, please let"
					+" us know on the GameDig issue tracker, thanks!\n"
				);
			}
			query.options.port = query.options.port_query;
			delete query.options.port_query;
		}
		
		// copy over options
		for(var i in options) query.options[i] = options[i];

		activeQueries.push(query);

		query.on('finished',function(state) {
			var i = activeQueries.indexOf(query);
			if(i >= 0) activeQueries.splice(i, 1);
		});
		
		process.nextTick(function() {
			query.start();
		});

		return query;
	}

};

module.exports = Gamedig;