From 3c38fe48fef80208f57fee80c23ab66b4eb8310a Mon Sep 17 00:00:00 2001
From: cetteup <me@cetteup.com>
Date: Tue, 13 Dec 2022 10:46:43 +0100
Subject: [PATCH] feat: Allow direct control of IP family to be returned by DNS
 lookup implements #306

---
 bin/gamedig.js     | 2 +-
 lib/DnsResolver.js | 7 ++++---
 lib/QueryRunner.js | 5 +++--
 protocols/core.js  | 2 +-
 4 files changed, 9 insertions(+), 7 deletions(-)

diff --git a/bin/gamedig.js b/bin/gamedig.js
index 4351b37..e85e3f2 100755
--- a/bin/gamedig.js
+++ b/bin/gamedig.js
@@ -5,7 +5,7 @@ const Minimist = require('minimist'),
 
 const argv = Minimist(process.argv.slice(2), {
     boolean: ['pretty','debug','givenPortOnly','requestRules'],
-    string: ['guildId','listenUdpPort']
+    string: ['guildId','listenUdpPort','ipFamily']
 });
 
 const debug = argv.debug;
diff --git a/lib/DnsResolver.js b/lib/DnsResolver.js
index 33aa041..5d9e0a6 100644
--- a/lib/DnsResolver.js
+++ b/lib/DnsResolver.js
@@ -20,10 +20,11 @@ class DnsResolver {
     /**
      * Response port will only be present if srv record was involved.
      * @param {string} host
+     * @param {number} ipFamily
      * @param {string=} srvRecordPrefix
      * @returns {Promise<{address:string, port:number=}>}
      */
-    async resolve(host, srvRecordPrefix) {
+    async resolve(host, ipFamily, srvRecordPrefix) {
         this.logger.debug("DNS Lookup: " + host);
 
         if(this.isIp(host)) {
@@ -52,7 +53,7 @@ class DnsResolver {
                     }
                     return {
                         port: srvPort,
-                        ...await this.resolve(srvHost, srvRecordPrefix)
+                        ...await this.resolve(srvHost, ipFamily, srvRecordPrefix)
                     };
                 }
                 this.logger.debug("No SRV Record");
@@ -62,7 +63,7 @@ class DnsResolver {
         }
 
         this.logger.debug("Standard Resolve: " + host);
-        const dnsResult = await dnsLookupAsync(host);
+        const dnsResult = await dnsLookupAsync(host, ipFamily);
         // For some reason, this sometimes returns a string address rather than an object.
         // I haven't been able to reproduce, but it's been reported on the issue tracker.
         let address;
diff --git a/lib/QueryRunner.js b/lib/QueryRunner.js
index 47244b7..3abb953 100644
--- a/lib/QueryRunner.js
+++ b/lib/QueryRunner.js
@@ -5,7 +5,8 @@ const GameResolver = require('./GameResolver'),
 const defaultOptions = {
     socketTimeout: 2000,
     attemptTimeout: 10000,
-    maxAttempts: 1
+    maxAttempts: 1,
+    ipFamily: 0
 };
 
 class QueryRunner {
@@ -19,7 +20,7 @@ class QueryRunner {
     async run(userOptions) {
         for (const key of Object.keys(userOptions)) {
             const value = userOptions[key];
-            if (['port'].includes(key)) {
+            if (['port', 'ipFamily'].includes(key)) {
                 userOptions[key] = parseInt(value);
             }
         }
diff --git a/protocols/core.js b/protocols/core.js
index 4885928..fe846d8 100644
--- a/protocols/core.js
+++ b/protocols/core.js
@@ -69,7 +69,7 @@ class Core extends EventEmitter {
     async runOnce() {
         const options = this.options;
         if (('host' in options) && !('address' in options)) {
-            const resolved = await this.dnsResolver.resolve(options.host, this.srvRecord);
+            const resolved = await this.dnsResolver.resolve(options.host, options.ipFamily, this.srvRecord);
             options.address = resolved.address;
             if (resolved.port) options.port = resolved.port;
         }