Merge pull request #63566 from default50/fix/s3-external-missing-key-warning

fix(files_external): guard optional S3 key in storage id computation

Author: susnux

apps/files_external/tests/Storage/Amazons3IdTest.php

@@ -0,0 +1,32 @@
+<?php
+
+declare(strict_types=1);
+/**
+ * SPDX-FileCopyrightText: 2026 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+namespace OCA\Files_External\Tests\Storage;
+
+use OCA\Files_External\Lib\Storage\AmazonS3;
+use Test\TestCase;
+
+/**
+ * Regression test for the storage id computation in AmazonS3::__construct().
+ *
+ * Constructs the storage directly (no live S3 backend) to exercise only the id
+ * derivation, which runs unconditionally in the constructor.
+ */
+#[\PHPUnit\Framework\Attributes\Group('S3')]
+class Amazons3IdTest extends TestCase {
+	/**
+	 * Mounts authenticating via the AWS SDK default credential chain (env, EC2
+	 * instance profile, ECS task role) carry no static `key` param. The id must
+	 * still be derivable without emitting an "Undefined array key" warning
+	 * (PHPUnit fails the test on any emitted warning).
+	 */
+	public function testConstructWithoutKey(): void {
+		$storage = new AmazonS3(['bucket' => 'test-bucket']);
+		$this->assertNotEmpty($storage->getId());
+	}
+}

lib/private/Files/ObjectStore/S3ConnectionTrait.php

@@ -64,6 +64,7 @@ protected function parseParams($params) {
 		$this->retriesMaxAttempts = $params['retriesMaxAttempts'] ?? 5;
 		$params['region'] = empty($params['region']) ? 'eu-west-1' : $params['region'];
 		$params['hostname'] = empty($params['hostname']) ? 's3.' . $params['region'] . '.amazonaws.com' : $params['hostname'];
+		$params['key'] = $params['key'] ?? '';
 		$params['s3-accelerate'] = $params['hostname'] === 's3-accelerate.amazonaws.com' || $params['hostname'] === 's3-accelerate.dualstack.amazonaws.com';
 		if (!isset($params['port']) || $params['port'] === '') {
 			$params['port'] = (isset($params['use_ssl']) && $params['use_ssl'] === false) ? 80 : 443;