webui: fix undefined array key warning

This PR fixes the issue that a PHP warning is thrown because
of a missing check if the array key exists.

1 files changed, 5 insertions, 1 deletions

diff --git a/webui/module/Pool/src/Pool/Model/PoolModel.php b/webui/module/Pool/src/Pool/Model/PoolModel.php
index d1e2d8ea9..2186e5d32 100644
--- a/webui/module/Pool/src/Pool/Model/PoolModel.php
+++ b/webui/module/Pool/src/Pool/Model/PoolModel.php
@@ -149,7 +149,11 @@ class PoolModel
 
          $matches = [];
          preg_match('/\s*Next\s*Pool\s*=\s*("|\')?(?<value>.*)(?(1)\1|)/i', $result, $matches);
-         return $matches["value"];
+         if(array_key_exists('value', $matches)) {
+           return $matches["value"];
+         } else {
+           return null;
+         }
       }
       else {
          throw new \Exception('Missing argument.');