From a817a1a070b4530eaeb07c90608e289e451c755b Mon Sep 17 00:00:00 2001
From: Pierre Rudloff <contact@rudloff.pro>
Date: Tue, 19 Dec 2017 11:37:55 +0100
Subject: [PATCH] Throw NotFoundException if results are empty in
 api_users_lookup

---
 include/api.php | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/include/api.php b/include/api.php
index ced1f1cbb8..6201b460a3 100644
--- a/include/api.php
+++ b/include/api.php
@@ -1494,16 +1494,24 @@ api_register_func('api/users/search', 'api_users_search');
  *
  * @return array|string
  * @throws UnauthorizedException
+ * @throws NotFoundException
  */
 function api_users_lookup($type)
 {
 	$users = array();
-	foreach (explode(',', $_REQUEST['user_id']) as $id) {
-		if (!empty($id)) {
-			$users[] = api_get_user(get_app(), $id);
+
+	if (x($_REQUEST['user_id'])) {
+		foreach (explode(',', $_REQUEST['user_id']) as $id) {
+			if (!empty($id)) {
+				$users[] = api_get_user(get_app(), $id);
+			}
 		}
 	}
 
+	if (empty($users)) {
+		throw new NotFoundException;
+	}
+
 	return api_format_data("users", $type, array('users' => $users));
 }
 
-- 
2.39.2