node-gamedig/protocols/minecraftping.js

94 lines
2.1 KiB
JavaScript

var varint = require('varint'),
async = require('async');
function varIntBuffer(num) {
return new Buffer(varint.encode(num));
}
function buildPacket(id,data) {
if(!data) data = new Buffer(0);
var idBuffer = varIntBuffer(id);
return Buffer.concat([
varIntBuffer(data.length+idBuffer.length),
idBuffer,
data
]);
}
module.exports = require('./core').extend({
run: function(state) {
var self = this;
var receivedData;
async.series([
function(c) {
// build and send handshake and status TCP packet
var portBuf = new Buffer(2);
portBuf.writeUInt16BE(self.options.port_query,0);
var addressBuf = new Buffer(self.options.address,'utf8');
var bufs = [
varIntBuffer(4),
varIntBuffer(addressBuf.length),
addressBuf,
portBuf,
varIntBuffer(1)
];
var outBuffer = Buffer.concat([
buildPacket(0,Buffer.concat(bufs)),
buildPacket(0)
]);
self.tcpSend(outBuffer, function(data) {
if(data.length < 10) return false;
var expected = varint.decode(data);
data = data.slice(varint.decode.bytesRead);
if(data.length < expected) return false;
receivedData = data;
c();
return true;
});
},
function(c) {
// parse response
var data = receivedData;
var packetId = varint.decode(data);
data = data.slice(varint.decode.bytesRead);
var strLen = varint.decode(data);
data = data.slice(varint.decode.bytesRead);
var str = data.toString('utf8');
var json;
try {
json = JSON.parse(str);
delete json.favicon;
if(self.debug) console.log(json);
} catch(e) {
return self.fatal('Invalid JSON');
}
state.raw.version = json.version.name;
state.maxplayers = json.players.max;
state.raw.description = json.description.text;
if(json.players.sample) {
for(var i = 0; i < json.players.sample.length; i++) {
state.players.push({
id: json.players.sample[i].id,
name: json.players.sample[i].name
});
}
}
while(state.players.length < json.players.online) {
state.players.push({});
}
self.finish(state);
}
]);
}
});