fix: idn ping errors

server/util-server.js

@@ -157,6 +157,18 @@ exports.pingAsync = function (
     deadline = PING_GLOBAL_TIMEOUT_DEFAULT,
     timeout = PING_PER_REQUEST_TIMEOUT_DEFAULT
 ) {
+    try {
+        // Convert IDN to punycode, then keep hostname
+        const url = new URL(`http://${destAddr}`);
+        destAddr = url.hostname;
+        // Enforce valid IPv6 address
+        if (destAddr.startsWith("[") && destAddr.endsWith("]")) {
+            destAddr = destAddr.slice(1, -1);
+        }
+    } catch (e) {
+        // ignore
+    }
+
     return new Promise((resolve, reject) => {
         ping.promise
             .probe(destAddr, {

src/pages/EditMonitor.vue

@@ -2260,7 +2260,13 @@ export default {
 
         defaultFriendlyName() {
             if (this.monitor.hostname) {
-                return this.monitor.hostname;
+                try {
+                    // Convert IDN to punycode
+                    const url = new URL(`http://${this.monitor.hostname}`);
+                    return url.hostname;
+                } catch (e) {
+                    return this.monitor.hostname;
+                }
             }
             if (this.monitor.system_service_name) {
                 return this.monitor.system_service_name;

test/backend-test/test-util-server.js

@@ -0,0 +1,47 @@
+const { describe, test } = require("node:test");
+const assert = require("node:assert");
+const { pingAsync } = require("../../server/util-server");
+
+describe("Server Utilities: pingAsync", () => {
+    test("should convert IDN domains to Punycode before pinging", async () => {
+        try {
+            // timeout 1s
+            await pingAsync("münchen.de", false, 1, "", true, 56, 1, 1);
+        } catch (e) {
+            if (e.message.includes("Parameter string not correctly encoded")) {
+                assert.fail("Ping failed with encoding error: IDN was not converted");
+            }
+            assert.ok(
+                e.message.includes("xn--mnchen-3ya.de"),
+                `Error message should contain "xn--mnchen-3ya.de". Got: ${e.message}`
+            );
+        }
+    });
+
+    test("should strip brackets from IPv6 addresses before pinging", async () => {
+        try {
+            // Cloudflare DNS
+            await pingAsync("[2606:4700:4700::1111]", true, 1, "", true, 56, 1, 1);
+        } catch (e) {
+            if (e.message.includes("[2606:4700:4700::1111]")) {
+                assert.fail(`Error message contained brackets, implying they were not stripped. Got: ${e.message}`);
+            }
+            // The error message should contain the raw IP without brackets
+            assert.ok(
+                e.message.includes("2606:4700:4700::1111"),
+                `Error message should contain the raw IP "2606:4700:4700::1111". Got: ${e.message}`
+            );
+        }
+    });
+
+    test("should handle standard ASCII domains correctly", async () => {
+        try {
+            await pingAsync("google.com", false, 1, "", true, 56, 1, 1);
+        } catch (e) {
+            if (e.message.includes("Parameter string not correctly encoded")) {
+                assert.fail("Ping failed with encoding error for ASCII domain");
+            }
+            assert.ok(e.message.includes("google.com"), `Error message should contain "google.com". Got: ${e.message}`);
+        }
+    });
+});