fix: Skip users that still exist in backendfix/resiliant-user-removal

Signed-off-by: Ferdinand Thiessen <opensource@fthiessen.de>

1 files changed, 56 insertions, 0 deletions

diff --git a/lib/private/User/PartiallyDeletedUsersBackend.php b/lib/private/User/PartiallyDeletedUsersBackend.php
new file mode 100644
index 00000000000..298ddaff6c6
--- /dev/null
+++ b/lib/private/User/PartiallyDeletedUsersBackend.php
@@ -0,0 +1,56 @@
+<?php
+
+/**
+ * SPDX-FileCopyrightText: 2024 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+namespace OC\User;
+
+use OCP\IConfig;
+use OCP\IUserBackend;
+use OCP\User\Backend\IGetHomeBackend;
+
+/**
+ * This is a "fake" backend for users that were deleted,
+ * but not properly removed from Nextcloud (e.g. an exception occurred).
+ * This backend is only needed because some APIs in user-deleted-events require a "real" user with backend.
+ */
+class PartiallyDeletedUsersBackend extends Backend implements IGetHomeBackend, IUserBackend {
+
+	public function __construct(
+		private IConfig $config,
+	) {
+	}
+
+	public function deleteUser($uid): bool {
+		// fake true, deleting failed users is automatically handled by User::delete()
+		return true;
+	}
+
+	public function getBackendName(): string {
+		return 'deleted users';
+	}
+
+	public function userExists($uid) {
+		return $this->config->getUserValue($uid, 'core', 'deleted') === 'true';
+	}
+
+	public function getHome(string $uid): string|false {
+		return $this->config->getUserValue($uid, 'core', 'deleted.home-path') ?: false;
+	}
+
+	public function getUsers($search = '', $limit = null, $offset = null) {
+		return $this->config->getUsersForUserValue('core', 'deleted', 'true');
+	}
+
+	/**
+	 * Unmark a user as deleted.
+	 * This typically the case if the user deletion failed in the backend but before the backend deleted the user,
+	 * meaning the user still exists so we unmark them as it still can be accessed (and deleted) normally.
+	 */
+	public function unmarkUser(string $userId): void {
+		$this->config->deleteUserValue($userId, 'core', 'deleted');
+		$this->config->deleteUserValue($userId, 'core', 'deleted.home-path');
+	}
+
+}