From 23299a9a07123f4c547714a99a0dd8194a1a7394 Mon Sep 17 00:00:00 2001
From: Timofey Gelazoniya <timofey@z4n.me>
Date: Wed, 25 Jun 2025 01:09:07 +0300
Subject: [PATCH] fix: add timeout to SRV record lookup

The `dns.promises.resolveSrv` function used for SRV record lookups
does not have a user-configurable timeout. This could cause the entire
`pingJava` operation to hang for an extended period if the target's
DNS server unresponsive.

To make the SRV lookup more robust and respect the user-provided
timeout, this commit switches to using the `dns.promises.Resolver`
class.
---
 lib/java.js | 19 ++++++++++++-------
 1 file changed, 12 insertions(+), 7 deletions(-)

diff --git a/lib/java.js b/lib/java.js
index 1150ff5..e2c4602 100644
--- a/lib/java.js
+++ b/lib/java.js
@@ -6,7 +6,7 @@
 "use strict";
 
 import net from "node:net";
-import dns from "node:dns/promises";
+import { Resolver } from "node:dns/promises";
 import createDebug from "debug";
 import * as varint from "./varint.js";
 
@@ -148,22 +148,27 @@ export async function pingJava(host, options = {}) {
 	let targetPort = fallbackPort;
 
 	try {
-		debug("attempting SRV lookup for _minecraft._tcp.%s", host);
-		const srvRecords = await dns.resolveSrv(`_minecraft._tcp.${host}`);
+		debug(
+			"attempting SRV lookup for _minecraft._tcp.%s with %dms timeout",
+			host,
+			timeout
+		);
+		const resolver = new Resolver({ timeout, tries: 3 });
+		const srvRecords = await resolver.resolveSrv(`_minecraft._tcp.${host}`);
 		if (srvRecords.length > 0) {
 			targetHost = srvRecords[0].name;
 			targetPort = srvRecords[0].port;
 			debug("SRV lookup successful, new target: %s:%d", targetHost, targetPort);
 		}
 	} catch (err) {
-		// Common errors like ENODATA or ENOTFOUND are expected when a server
-		// does not have an SRV record, so we ignore them and proceed
+		// Common errors like ENODATA, ENOTFOUND, or a DNS timeout (ETIMEOUT) are expected
+		// when a server does not have an SRV record, so we ignore them and proceed.
+		const nonFatalDnsCodes = ["ENODATA", "ENOTFOUND", "ETIMEOUT"];
 		if (
 			err instanceof Error &&
 			"code" in err &&
-			(err.code === "ENODATA" || err.code === "ENOTFOUND")
+			nonFatalDnsCodes.includes(err.code)
 		) {
-			// Non fatal DNS error, log it and continue
 			debug("SRV lookup for %s failed (%s), using fallback.", host, err.code);
 		} else {
 			// Re-throw anything else to fail the operation