protected function findGroupBy($key, $value)
{
if (!empty($value)) {
$group = $this->container->get('fos_user.group_manager')->{'findGroupBy' . ucfirst($key)}($value);
}
if (empty($group)) {
throw new NotFoundHttpException(sprintf('The group with "%s" does not exist for value "%s"', $key, $value));
}
return $group;
}