owncloud/core

<?php
/**
 * @author Morris Jobke <hey@morrisjobke.de>
 * @author Pierre Jochem <pierrejochem@msn.com>
 * @author Robin Appelman <icewind@owncloud.com>
 * @author Sergio Bertolín <sbertolin@solidgear.es>
 * @author Thomas Müller <thomas.mueller@tmit.eu>
 * @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\DAV\Connector\Sabre;

use OCP\Files\FileContentNotAllowedException;
use OCP\ILogger;
use Sabre\DAV\Exception;
use Sabre\HTTP\Response;

class ExceptionLoggerPlugin extends \Sabre\DAV\ServerPlugin {
    protected $nonFatalExceptions = [
        'Sabre\DAV\Exception\NotAuthenticated' => true,
        // the sync client uses this to find out whether files exist,
        // so it is not always an error, log it as debug
        'Sabre\DAV\Exception\NotFound' => true,
        // this one mostly happens when the same file is uploaded at
        // exactly the same time from two clients, only one client
        // wins, the second one gets "Precondition failed"
        'Sabre\DAV\Exception\PreconditionFailed' => true,
        // forbidden can be expected when trying to upload to
        // read-only folders for example
        'Sabre\DAV\Exception\Forbidden' => true,
        // Custom exception similar to NotAuthenticated
        'OCA\DAV\Connector\Sabre\Exception\PasswordLoginForbidden' => true,
        // Happens when an external storage or federated share is temporarily
        // not available
        'Sabre\DAV\Exception\StorageNotAvailableException' => true,
        'OCP\Files\StorageNotAvailableException' => true,
        // Locked exceptions could be fine if the file is truly locked
        'Sabre\DAV\Exception\Locked' => true,
        'OCA\DAV\Connector\Sabre\Exception\FileLocked' => true,  // thrown by the LockPlugin
        //If the exception is InsufficientStorage, then log a debug message
        'Sabre\DAV\Exception\InsufficientStorage' => true
    ];

    /** @var string */
    private $appName;

    /** @var ILogger */
    private $logger;

    /**
     * @param string $loggerAppName app name to use when logging
     * @param ILogger $logger
     */
    public function __construct($loggerAppName, $logger) {
        $this->appName = $loggerAppName;
        $this->logger = $logger;
    }

    /**
     * This initializes the plugin.
     *
     * This function is called by \Sabre\DAV\Server, after
     * addPlugin is called.
     *
     * This method should set up the required event subscriptions.
     *
     * @param \Sabre\DAV\Server $server
     * @return void
     */
    public function initialize(\Sabre\DAV\Server $server) {
        $server->on('exception', [$this, 'logException'], 10);
    }

    /**
     * Log exception
     *
     */
    public function logException(\Throwable $ex) {
        if ($ex->getPrevious() instanceof FileContentNotAllowedException) {
            //Don't log because its already been logged may be by different
            //app or so.
            return null;
        }
        $exceptionClass = \get_class($ex);
        $level = \OCP\Util::FATAL;
        if (isset($this->nonFatalExceptions[$exceptionClass])) {
            $level = \OCP\Util::DEBUG;
        }

        $previous = $ex->getPrevious();
        if ($previous !== null) {
            $previousExceptionClass = \get_class($previous);
            if (isset($this->nonFatalExceptions[$previousExceptionClass])) {
                $level = \OCP\Util::DEBUG;
            }
        }
        $message = $ex->getMessage();
        if ($ex instanceof Exception) {
            if (empty($message)) {
                $response = new Response($ex->getHTTPCode());
                $message = $response->getStatusText();
            }
            $message = "HTTP/1.1 {$ex->getHTTPCode()} $message";
        }

        $this->logger->logException(
            $ex,
            [
                'app'         => $this->appName,
                'message'     => 'Exception: '.$message,
                'level'     => $level
            ]
        );
    }
}