nextcloud/apps/contacts/ajax/deletebook.php

<?php
/**
 * ownCloud - Addressbook
 *
 * @author Jakob Sack
 * @copyright 2011 Jakob Sack mail@jakobsack.de
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU AFFERO GENERAL PUBLIC LICENSE
 * License as published by the Free Software Foundation; either
 * version 3 of the License, or any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU AFFERO GENERAL PUBLIC LICENSE for more details.
 *
 * You should have received a copy of the GNU Affero General Public
 * License along with this library.  If not, see <http://www.gnu.org/licenses/>.
 *
 */

// Init owncloud
 

// Check if we are a user
OCP\JSON::checkLoggedIn();
OCP\JSON::checkAppEnabled('contacts');

//$id = $_GET['id'];
$id = $_POST['id'];
OC_Contacts_App::getAddressbook( $id ); // is owner access check

OC_Contacts_Addressbook::delete($id);
OCP\JSON::success(array('data' => array( 'id' => $id )));