nextcloud-server/apps/dav/lib/Connector/Sabre/MaintenancePlugin.php

<?php

/**
 * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
 * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
 * SPDX-License-Identifier: AGPL-3.0-only
 */
namespace OCA\DAV\Connector\Sabre;

use OCA\DAV\Exception\ServerMaintenanceMode;
use OCP\IConfig;
use OCP\IL10N;
use OCP\Util;
use Sabre\DAV\Exception\ServiceUnavailable;
use Sabre\DAV\ServerPlugin;

class MaintenancePlugin extends ServerPlugin {

	/** @var IConfig */
	private $config;

	/** @var \OCP\IL10N */
	private $l10n;

	/**
	 * Reference to main server object
	 *
	 * @var Server
	 */
	private $server;

	/**
	 * @param IConfig $config
	 */
	public function __construct(IConfig $config, IL10N $l10n) {
		$this->config = $config;
		$this->l10n = \OC::$server->getL10N('dav');
	}


	/**
	 * 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) {
		$this->server = $server;
		$this->server->on('beforeMethod:*', [$this, 'checkMaintenanceMode'], 1);
	}

	/**
	 * This method is called before any HTTP method and returns http status code 503
	 * in case the system is in maintenance mode.
	 *
	 * @throws ServiceUnavailable
	 * @return bool
	 */
	public function checkMaintenanceMode() {
		if ($this->config->getSystemValueBool('maintenance')) {
			throw new ServerMaintenanceMode($this->l10n->t('System is in maintenance mode.'));
		}
		if (Util::needUpgrade()) {
			throw new ServerMaintenanceMode($this->l10n->t('Upgrade needed'));
		}

		return true;
	}
}