silverstripe-framework/tasks/ScheduledTask.php
2013-02-07 16:49:52 +01:00

61 lines
2.3 KiB
PHP

<?php
/**
* Abstract task representing scheudled tasks.
*
* Scheduled tasks are tasks that are run at a certain time or set interval. For example, notify a page owner that
* their page is about to expire. Scheduled tasks are implemented as singleton instances and a single
* instance is responsibly directly or indirectly for executing all tasks that should be run at that time.
*
* You can use the different subclasses {@link HourlyTask}, {@link DailyTask},
* {@link WeeklyTask} to determine when a task should be run,
* and use automation tools such as unix cron to trigger them.
*
* <b>Usage</b>
*
* Implement a daily task by extending DailyTask and implementing process().
*
* <code>
* class MyTask extends DailyTask {
* function process() {
* // implement your task here
* }
* }
* </code>
*
* You can also implement the index() method to overwrite which singleton classes are instantiated and processed.
* By default, all subclasses of the task are instantiated and used. For the DailyTask class, this means
* that an instance of each subclass of DailyTask will be created.
*
* You can test your task from the command line by running the following command
* (replace <MyTask> is the classname of your task):
*
* <code>framework/cli-script.php /<MyTask></code>
*
* To perform all Daily tasks, run from the command line:
*
* <code>cli-script.php /DailyTask</code>
*
* <b>Example Cron Definition</b>
*
* <code>
* # Quarter-hourly task (every hour at 25 minutes past) (remove space between first * and /15)
* * /15 * * * * www-data /webroot/framework/cli-script.php /QuarterHourlyTask > /var/log/quarterhourlytask.log
*
* # HourlyTask (every hour at 25 minutes past)
* 25 * * * * www-data /webroot/framework/cli-script.php /HourlyTask > /var/log/hourlytask.log
*
* # DailyTask (every day at 6:25am)
* 25 6 * * * www-data /webroot/framework/cli-script.php /DailyTask > /var/log/dailytask.log
*
* # WeelkyTask (every Monday at 6:25am)
* 25 6 1 * * www-data /webroot/framework/cli-script.php /WeeklyTask > /var/log/weeklytask.log
* </code>
*
* @todo Improve documentation
* @package framework
* @subpackage cron
*/
abstract class ScheduledTask extends CliController {
// this class exists as a logical extension
}