public function loadExtensionData($uuid, $extensionName, $webspaceKey, $languageCode)
{
$structure = $this->getMapper()->load($uuid, $webspaceKey, $languageCode);
// extract extension
$extensionData = $structure->getExt();
$data = $extensionData[$extensionName];
// add uuid and path
$data['id'] = $structure->getUuid();
$data['path'] = $structure->getPath();
// prepare data
$data['_links'] = ['self' => ['href' => $this->apiBasePath . '/' . $uuid . '/' . $extensionName . '?webspace=' . $webspaceKey . '&language=' . $languageCode]];
return $data;
}