fix: log actual adapter-node listening address

.changeset/twelve-buses-smile.md

@@ -0,0 +1,5 @@
+---
+'@sveltejs/adapter-node': patch
+---
+
+fix: log the actual adapter-node listening address

packages/adapter-node/src/index.js

@@ -3,6 +3,7 @@ import process from 'node:process';
 import { handler } from 'HANDLER';
 import { env, timeout_env } from 'ENV';
 import polka from 'polka';
+import { format_listening_address } from '../utils.js';
 
 export const path = env('SOCKET_PATH', false);
 export const host = env('HOST', '0.0.0.0');
@@ -57,7 +58,7 @@ if (socket_activation) {
 	});
 } else {
 	server.listen({ path, host, port }, () => {
-		console.log(`Listening on ${path || `http://${host}:${port}`}`);
+		console.log(`Listening on ${format_listening_address(path, host, port, httpServer.address())}`);
 	});
 }
 

packages/adapter-node/tests/utils.spec.ts

@@ -1,5 +1,5 @@
 import { expect, test, describe } from 'vitest';
-import { parse_as_bytes, parse_origin } from '../utils.js';
+import { format_listening_address, parse_as_bytes, parse_origin } from '../utils.js';
 
 describe('parse_as_bytes', () => {
 	test.each([
@@ -47,3 +47,37 @@ describe('parse_origin', () => {
 		}
 	);
 });
+
+describe('format_listening_address', () => {
+	test('uses the actual listening port assigned by the server', () => {
+		expect(
+			format_listening_address(false, '0.0.0.0', '0', {
+				address: '0.0.0.0',
+				family: 'IPv4',
+				port: 43521
+			})
+		).toBe('http://0.0.0.0:43521');
+	});
+
+	test('formats IPv6 addresses as valid URLs', () => {
+		expect(
+			format_listening_address(false, '::1', '3000', {
+				address: '::1',
+				family: 'IPv6',
+				port: 3000
+			})
+		).toBe('http://[::1]:3000');
+	});
+
+	test('falls back to configured host and port when the address is unavailable', () => {
+		expect(format_listening_address(false, 'localhost', '3000', null)).toBe(
+			'http://localhost:3000'
+		);
+	});
+
+	test('returns the socket path unchanged', () => {
+		expect(format_listening_address('/tmp/sveltekit.sock', '0.0.0.0', '3000', null)).toBe(
+			'/tmp/sveltekit.sock'
+		);
+	});
+});

packages/adapter-node/utils.js

@@ -1,3 +1,5 @@
+import { format } from 'node:url';
+
 /**
  * Parses the given value into number of bytes.
  *
@@ -50,3 +52,32 @@ export function parse_origin(value) {
 
 	return url.origin;
 }
+
+/**
+ * Formats the address the server is listening on.
+ *
+ * @param {string | false} path
+ * @param {string} host
+ * @param {string | false} port
+ * @param {import('node:net').AddressInfo | string | null} address
+ * @returns {string}
+ */
+export function format_listening_address(path, host, port, address) {
+	if (path) {
+		return path;
+	}
+
+	if (address && typeof address === 'object') {
+		return format({
+			protocol: 'http:',
+			hostname: address.address,
+			port: address.port
+		});
+	}
+
+	return format({
+		protocol: 'http:',
+		hostname: host,
+		port: String(port)
+	});
+}