Check that custom session path exists, create if not, if can't create then use default (#19431)

Author: Michael Babker

administrator/components/com_config/Model/ApplicationModel.php

@@ -14,6 +14,8 @@
 use Joomla\CMS\Access\Access;
 use Joomla\CMS\Access\Rules;
 use Joomla\CMS\Component\ComponentHelper;
+use Joomla\CMS\Filesystem\Folder;
+use Joomla\CMS\Filesystem\Path;
 use Joomla\CMS\MVC\Model\FormModel;
 use Joomla\CMS\Table\Asset;
 use Joomla\CMS\Table\Table;
@@ -315,6 +317,43 @@ public function save($data)
 			}
 		}
 
+		// Ensure custom session file path exists or try to create it if changed
+		if (!empty($data['session_filesystem_path']))
+		{
+			$currentPath = $prev['session_filesystem_path'] ?? null;
+
+			if ($currentPath)
+			{
+				$currentPath = Path::clean($currentPath);
+			}
+
+			$data['session_filesystem_path'] = Path::clean($data['session_filesystem_path']);
+
+			if ($currentPath !== $data['session_filesystem_path'])
+			{
+				if (!Folder::exists($data['session_filesystem_path']) && !Folder::create($data['session_filesystem_path']))
+				{
+					try
+					{
+						\JLog::add(
+							\JText::sprintf('COM_CONFIG_ERROR_CUSTOM_SESSION_FILESYSTEM_PATH_NOTWRITABLE_USING_DEFAULT', $data['session_filesystem_path']),
+							\JLog::WARNING,
+							'jerror'
+						);
+					}
+					catch (\RuntimeException $logException)
+					{
+						$app->enqueueMessage(
+							\JText::sprintf('COM_CONFIG_ERROR_CUSTOM_SESSION_FILESYSTEM_PATH_NOTWRITABLE_USING_DEFAULT', $data['session_filesystem_path']),
+							'warning'
+						);
+					}
+
+					$data['session_filesystem_path'] = $currentPath;
+				}
+			}
+		}
+
 		// Set the shared session configuration
 		if (isset($data['shared_session']))
 		{

administrator/language/en-GB/en-GB.com_config.ini

@@ -19,6 +19,7 @@ COM_CONFIG_ERROR_CONFIG_EXTENSION_NOT_FOUND="The Global Configuration extension
 COM_CONFIG_ERROR_CONFIGURATION_PHP_NOTUNWRITABLE="Could not make configuration.php unwritable."
 COM_CONFIG_ERROR_CONFIGURATION_PHP_NOTWRITABLE="Could not make configuration.php writable."
 COM_CONFIG_ERROR_CUSTOM_CACHE_PATH_NOTWRITABLE_USING_DEFAULT="The folder at %1$s is not writable and cannot be used for the cache, using the default %2$s instead."
+COM_CONFIG_ERROR_CUSTOM_SESSION_FILESYSTEM_PATH_NOTWRITABLE_USING_DEFAULT="The folder at %s is not writable and cannot be used to store session data, the default PHP path will be used instead."
 COM_CONFIG_ERROR_HELPREFRESH_ERROR_STORE="The new Help Sites list could not be saved."
 COM_CONFIG_ERROR_HELPREFRESH_FETCH="The current Help Sites list could not be fetched from the remote server."
 COM_CONFIG_ERROR_ROOT_ASSET_NOT_FOUND="The asset for global configuration could not be found. Permissions have not been saved."