public function add()
{
if (Kadmin::already($_POST['id'])) {
throw new Exception('KADMIN ALREADY EXISTS', 409);
}
$admin = new Kadmin();
$admin->setId($_POST['id']);
$admin->setPassword($_POST['password']);
$admin->setDisplayName($_POST['displayName']);
$admin->setType($_POST['type']);
if (array_key_exists('mail', $_POST)) {
$admin->setMail($_POST['mail']);
}
$admin->save();
return array('kadminId' => $admin->getId());
}