[feature/system-cron] Refactored cron task naming, loading and running.

PHPBB3-9596

phpBB/includes/cron/cron_task.php

@@ -0,0 +1,60 @@
+<?php
+/**
+*
+* @package phpBB3
+* @version $Id$
+* @copyright (c) 2010 phpBB Group
+* @license http://opensource.org/licenses/gpl-license.php GNU Public License
+*
+*/
+
+/**
+* @ignore
+*/
+if (!defined('IN_PHPBB'))
+{
+	exit;
+}
+
+/**
+* Cron task interface
+* @package phpBB3
+*/
+interface cron_task
+{
+	/**
+	* Runs this cron task.
+	*/
+	public function run();
+
+	/**
+	* Returns whether this cron task can run, given current board configuration.
+	*
+	* For example, a cron task that prunes forums can only run when
+	* forum pruning is enabled.
+	*/
+	public function is_runnable();
+
+	/**
+	* Returns whether this cron task should run now, because enough time
+	* has passed since it was last run.
+	*/
+	public function should_run();
+
+	/**
+	* Returns whether this cron task can be run in shutdown function.
+	*/
+	public function is_shutdown_function_safe();
+}
+
+/**
+* Parametrized cron task interface
+* @package phpBB3
+*/
+interface parametrized_cron_task extends cron_task
+{
+	/**
+	* Returns parameters of this cron task as a query string.
+	*/
+	public function get_url_query_string();
+}