owncloud/core

<?php
/**
 * @author Morris Jobke <hey@morrisjobke.de>
 * @author Robin Appelman <icewind@owncloud.com>
 * @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 OC\Files\External;

use OCP\Files\Storage;
use OC\Files\Mount\MountPoint;
use OCP\Files\Storage\IStorageFactory;
use OCP\Files\Config\IMountProvider;
use OCP\IUser;
use OCP\Files\External\Service\IUserStoragesService;
use OCP\Files\External\Service\IUserGlobalStoragesService;
use OCP\Files\External\IStorageConfig;
use OC\Files\Storage\FailedStorage;
use OCP\IConfig;
use OCP\ISession;

/**
 * Make the old files_external config work with the new public mount config api
 */
class ConfigAdapter implements IMountProvider {
    /** @var IConfig */
    private $config;

    /** @var IUserStoragesService */
    private $userStoragesService;

    /** @var IUserGlobalStoragesService */
    private $userGlobalStoragesService;

    /** @var ISession */
    private $session;

    /**
     * @param IUserStoragesService $userStoragesService
     * @param IUserGlobalStoragesService $userGlobalStoragesService
     */
    public function __construct(
        IConfig $config,
        IUserStoragesService $userStoragesService,
        IUserGlobalStoragesService $userGlobalStoragesService,
        ISession $session
    ) {
        $this->config = $config;
        $this->userStoragesService = $userStoragesService;
        $this->userGlobalStoragesService = $userGlobalStoragesService;
        $this->session = $session;
    }

    /**
     * Process storage ready for mounting
     *
     * @param IStorageConfig $storage
     * @param IUser $user
     */
    private function prepareStorageConfig(IStorageConfig &$storage, IUser $user) {
        foreach ($storage->getBackendOptions() as $option => $value) {
            $storage->setBackendOption($option, $this->setUserVars(
                $user->getUserName(),
                $value
            ));
        }

        $objectStore = $storage->getBackendOption('objectstore');
        if ($objectStore) {
            $objectClass = $objectStore['class'];
            if (!\is_subclass_of($objectClass, '\OCP\Files\ObjectStore\IObjectStore')) {
                throw new \InvalidArgumentException('Invalid object store');
            }
            $storage->setBackendOption('objectstore', new $objectClass($objectStore));
        }

        $storage->getAuthMechanism()->manipulateStorageConfig($storage, $user);
        $storage->getBackend()->manipulateStorageConfig($storage, $user);
    }

    /**
     * Construct the storage implementation
     *
     * @param IStorageConfig $storageConfig
     * @return Storage
     */
    private function constructStorage(IStorageConfig $storageConfig) {
        $class = $storageConfig->getBackend()->getStorageClass();
        $storage = new $class($storageConfig->getBackendOptions());

        // auth mechanism should fire first
        $storage = $storageConfig->getBackend()->wrapStorage($storage);
        $storage = $storageConfig->getAuthMechanism()->wrapStorage($storage);

        return $storage;
    }

    /**
     * Get all mountpoints applicable for the user
     *
     * @param \OCP\IUser $user
     * @param \OCP\Files\Storage\IStorageFactory $loader
     * @return \OCP\Files\Mount\IMountPoint[]
     */
    public function getMountsForUser(IUser $user, IStorageFactory $loader) {
        $mounts = [];

        // setUser is in UserTrait.
        /* @phan-suppress-next-line PhanUndeclaredMethod */
        $this->userStoragesService->setUser($user);
        /* @phan-suppress-next-line PhanUndeclaredMethod */
        $this->userGlobalStoragesService->setUser($user);

        foreach ($this->userGlobalStoragesService->getUniqueStorages() as $storage) {
            try {
                $this->prepareStorageConfig($storage, $user);
                $impl = $this->constructStorage($storage);
            } catch (\Exception $e) {
                // propagate exception into filesystem
                $impl = new FailedStorage(['exception' => $e]);
            }

            $mount = new MountPoint(
                $impl,
                '/' . $user->getUID() . '/files' . $storage->getMountPoint(),
                null,
                $loader,
                $storage->getMountOptions()
            );
            $mounts[$storage->getMountPoint()] = $mount;
        }

        $allowUserMountSharing = $this->config->getAppValue('core', 'allow_user_mount_sharing', 'yes') === 'yes';
        foreach ($this->userStoragesService->getStorages() as $storage) {
            try {
                $this->prepareStorageConfig($storage, $user);
                $impl = $this->constructStorage($storage);
            } catch (\Exception $e) {
                // propagate exception into filesystem
                $impl = new FailedStorage(['exception' => $e]);
            }

            $mountOptions = $storage->getMountOptions();
            if (!$allowUserMountSharing) {
                $mountOptions['enable_sharing'] = false;
            }

            $mount = new PersonalMount(
                $this->userStoragesService,
                $storage->getId(),
                $impl,
                '/' . $user->getUID() . '/files' . $storage->getMountPoint(),
                null,
                $loader,
                $mountOptions
            );
            $mounts[$storage->getMountPoint()] = $mount;
        }

        // resetUser is in UserTrait.
        /* @phan-suppress-next-line PhanUndeclaredMethod */
        $this->userStoragesService->resetUser();
        /* @phan-suppress-next-line PhanUndeclaredMethod */
        $this->userGlobalStoragesService->resetUser();

        return $mounts;
    }

    /**
     * fill in the correct values for $user
     *
     * @param string $user user value
     * @param string|array $input
     * @return string
     */
    private function setUserVars($user, $input) {
        if (\is_array($input)) {
            foreach ($input as $key => $value) {
                if (\is_string($value)) {
                    $input[$key] = \str_replace('$user', $user, $value);
                }
            }
        } else {
            if (\is_string($input)) {
                $input = \str_replace('$user', $user, $input);
            }
        }
        return $input;
    }
}