owncloud/core

<?php
/**
 * @author Robin McCorkell <robin@mccorkell.me.uk>
 * @author Vincent Petry <pvince81@owncloud.com>
 *
 * @copyright Copyright (c) 2018, ownCloud GmbH
 * @license AGPL-3.0
 *
 * This code is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License, version 3,
 * as published by the Free Software Foundation.
 *
 * This program 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, version 3,
 * along with this program.  If not, see <http://www.gnu.org/licenses/>
 *
 */

namespace OCA\Files_External\Lib;

use OC\Files\External\MissingDependency;

/**
 * Polyfill for checking dependencies using legacy Storage::checkDependencies()
 */
trait LegacyDependencyCheckPolyfill {
    /**
     * @return string
     */
    abstract public function getStorageClass();

    /**
     * Check if object is valid for use
     *
     * @return MissingDependency[] Unsatisfied dependencies
     */
    public function checkDependencies() {
        $ret = [];

        $result = \call_user_func([$this->getStorageClass(), 'checkDependencies']);
        if ($result !== true) {
            if (!\is_array($result)) {
                $result = [$result];
            }
            foreach ($result as $key => $value) {
                if (!($value instanceof MissingDependency)) {
                    $module = null;
                    $message = null;
                    if (\is_numeric($key)) {
                        $module = $value;
                    } else {
                        $module = $key;
                        $message = $value;
                    }
                    $value = new MissingDependency($module);
                    $value->setMessage($message);
                }
                $ret[] = $value;
            }
        }

        return $ret;
    }
}