Add support for udp bind port override (3.0.5) Fixes #149

lib/GlobalUdpSocket.js

@@ -1,25 +1,29 @@
-const dgram = require('dgram'),
-    HexUtil = require('./HexUtil'),
-    Logger = require('./Logger');
+const dgram = require('dgram');
+const HexUtil = require('./HexUtil');
+const Logger = require('./Logger');
+const util = require('util');
 
 class GlobalUdpSocket {
-    constructor() {
+    constructor({port}) {
         this.socket = null;
         this.callbacks = new Set();
         this.debuggingCallbacks = new Set();
         this.logger = new Logger();
+        this.port = port;
     }
 
-    _getSocket() {
+    async _getSocket() {
         if (!this.socket) {
-            const udpSocket = this.socket = dgram.createSocket('udp4');
+            const udpSocket = dgram.createSocket({
+                type: 'udp4',
+                reuseAddr: true
+            });
             udpSocket.unref();
-            udpSocket.bind();
             udpSocket.on('message', (buffer, rinfo) => {
                 const fromAddress = rinfo.address;
                 const fromPort = rinfo.port;
                 this.logger.debug(log => {
-                    log(fromAddress + ':' + fromPort + " <--UDP");
+                    log(fromAddress + ':' + fromPort + " <--UDP(" + this.port + ")");
                     log(HexUtil.debugDump(buffer));
                 });
                 for (const cb of this.callbacks) {
@@ -29,12 +33,22 @@ class GlobalUdpSocket {
             udpSocket.on('error', e => {
                 this.logger.debug("UDP ERROR:", e);
             });
+            await util.promisify(udpSocket.bind).bind(udpSocket)(this.port);
+            this.port = udpSocket.address().port;
+            this.socket = udpSocket;
         }
         return this.socket;
     }
 
-    send(buffer, address, port) {
-        this._getSocket().send(buffer,0,buffer.length,port,address);
+    async send(buffer, address, port, debug) {
+        const socket = await this._getSocket();
+        if (debug) {
+            this.logger._print(log => {
+                log(address + ':' + port + " UDP(" + this.port + ")-->");
+                log(HexUtil.debugDump(buffer));
+            });
+        }
+        await util.promisify(socket.send).bind(socket)(buffer,0,buffer.length,port,address);
     }
 
     addCallback(callback, debug) {

lib/QueryRunner.js

@@ -9,8 +9,10 @@ const defaultOptions = {
 };
 
 class QueryRunner {
-    constructor() {
-        this.udpSocket = new GlobalUdpSocket();
+    constructor(runnerOpts = {}) {
+        this.udpSocket = new GlobalUdpSocket({
+            port: runnerOpts.listenUdpPort
+        });
         this.gameResolver = new GameResolver();
         this.protocolResolver = new ProtocolResolver();
     }

lib/index.js

@@ -3,8 +3,8 @@ const QueryRunner = require('./QueryRunner');
 let singleton = null;
 
 class Gamedig {
-    constructor() {
-        this.queryRunner = new QueryRunner();
+    constructor(runnerOpts) {
+        this.queryRunner = new QueryRunner(runnerOpts);
     }
 
     async query(userOptions) {