/Web/wp-includes/cron.php

  1<?php
  2/**
  3 * WordPress CRON API
  4 *
  5 * @package WordPress
  6 */
  7
  8/**
  9 * Schedules a hook to run only once.
 10 *
 11 * Schedules a hook which will be executed once by the WordPress actions core at
 12 * a time which you specify. The action will fire off when someone visits your
 13 * WordPress site, if the schedule time has passed.
 14 *
 15 * @since 2.1.0
 16 * @link http://codex.wordpress.org/Function_Reference/wp_schedule_single_event
 17 *
 18 * @param int $timestamp Timestamp for when to run the event.
 19 * @param string $hook Action hook to execute when cron is run.
 20 * @param array $args Optional. Arguments to pass to the hook's callback function.
 21 */
 22function wp_schedule_single_event( $timestamp, $hook, $args = array()) {
 23	// don't schedule a duplicate if there's already an identical event due in the next 10 minutes
 24	$next = wp_next_scheduled($hook, $args);
 25	if ( $next && $next <= $timestamp + 600 )
 26		return;
 27
 28	$crons = _get_cron_array();
 29	$event = (object) array( 'hook' => $hook, 'timestamp' => $timestamp, 'schedule' => false, 'args' => $args );
 30	$event = apply_filters('schedule_event', $event);
 31
 32	// A plugin disallowed this event
 33	if ( ! $event )
 34		return false;
 35
 36	$key = md5(serialize($event->args));
 37
 38	$crons[$event->timestamp][$event->hook][$key] = array( 'schedule' => $event->schedule, 'args' => $event->args );
 39	uksort( $crons, "strnatcasecmp" );
 40	_set_cron_array( $crons );
 41}
 42
 43/**
 44 * Schedule a periodic event.
 45 *
 46 * Schedules a hook which will be executed by the WordPress actions core on a
 47 * specific interval, specified by you. The action will trigger when someone
 48 * visits your WordPress site, if the scheduled time has passed.
 49 *
 50 * Valid values for the recurrence are hourly, daily and twicedaily. These can
 51 * be extended using the cron_schedules filter in wp_get_schedules().
 52 *
 53 * Use wp_next_scheduled() to prevent duplicates
 54 *
 55 * @since 2.1.0
 56 *
 57 * @param int $timestamp Timestamp for when to run the event.
 58 * @param string $recurrence How often the event should recur.
 59 * @param string $hook Action hook to execute when cron is run.
 60 * @param array $args Optional. Arguments to pass to the hook's callback function.
 61 * @return bool|null False on failure, null when complete with scheduling event.
 62 */
 63function wp_schedule_event( $timestamp, $recurrence, $hook, $args = array()) {
 64	$crons = _get_cron_array();
 65	$schedules = wp_get_schedules();
 66
 67	if ( !isset( $schedules[$recurrence] ) )
 68		return false;
 69
 70	$event = (object) array( 'hook' => $hook, 'timestamp' => $timestamp, 'schedule' => $recurrence, 'args' => $args, 'interval' => $schedules[$recurrence]['interval'] );
 71	$event = apply_filters('schedule_event', $event);
 72
 73	// A plugin disallowed this event
 74	if ( ! $event )
 75		return false;
 76
 77	$key = md5(serialize($event->args));
 78
 79	$crons[$event->timestamp][$event->hook][$key] = array( 'schedule' => $event->schedule, 'args' => $event->args, 'interval' => $event->interval );
 80	uksort( $crons, "strnatcasecmp" );
 81	_set_cron_array( $crons );
 82}
 83
 84/**
 85 * Reschedule a recurring event.
 86 *
 87 * @since 2.1.0
 88 *
 89 * @param int $timestamp Timestamp for when to run the event.
 90 * @param string $recurrence How often the event should recur.
 91 * @param string $hook Action hook to execute when cron is run.
 92 * @param array $args Optional. Arguments to pass to the hook's callback function.
 93 * @return bool|null False on failure. Null when event is rescheduled.
 94 */
 95function wp_reschedule_event( $timestamp, $recurrence, $hook, $args = array()) {
 96	$crons = _get_cron_array();
 97	$schedules = wp_get_schedules();
 98	$key = md5(serialize($args));
 99	$interval = 0;
100
101	// First we try to get it from the schedule
102	if ( 0 == $interval )
103		$interval = $schedules[$recurrence]['interval'];
104	// Now we try to get it from the saved interval in case the schedule disappears
105	if ( 0 == $interval )
106		$interval = $crons[$timestamp][$hook][$key]['interval'];
107	// Now we assume something is wrong and fail to schedule
108	if ( 0 == $interval )
109		return false;
110
111	$now = time();
112
113	if ( $timestamp >= $now )
114		$timestamp = $now + $interval;
115	else
116		$timestamp = $now + ($interval - (($now - $timestamp) % $interval));
117
118	wp_schedule_event( $timestamp, $recurrence, $hook, $args );
119}
120
121/**
122 * Unschedule a previously scheduled cron job.
123 *
124 * The $timestamp and $hook parameters are required, so that the event can be
125 * identified.
126 *
127 * @since 2.1.0
128 *
129 * @param int $timestamp Timestamp for when to run the event.
130 * @param string $hook Action hook, the execution of which will be unscheduled.
131 * @param array $args Arguments to pass to the hook's callback function.
132 * Although not passed to a callback function, these arguments are used
133 * to uniquely identify the scheduled event, so they should be the same
134 * as those used when originally scheduling the event.
135 */
136function wp_unschedule_event( $timestamp, $hook, $args = array() ) {
137	$crons = _get_cron_array();
138	$key = md5(serialize($args));
139	unset( $crons[$timestamp][$hook][$key] );
140	if ( empty($crons[$timestamp][$hook]) )
141		unset( $crons[$timestamp][$hook] );
142	if ( empty($crons[$timestamp]) )
143		unset( $crons[$timestamp] );
144	_set_cron_array( $crons );
145}
146
147/**
148 * Unschedule all cron jobs attached to a specific hook.
149 *
150 * @since 2.1.0
151 *
152 * @param string $hook Action hook, the execution of which will be unscheduled.
153 * @param array $args Optional. Arguments that were to be pass to the hook's callback function.
154 */
155function wp_clear_scheduled_hook( $hook, $args = array() ) {
156	// Backward compatibility
157	// Previously this function took the arguments as discrete vars rather than an array like the rest of the API
158	if ( !is_array($args) ) {
159		_deprecated_argument( __FUNCTION__, '3.0', __('This argument has changed to an array to match the behavior of the other cron functions.') );
160		$args = array_slice( func_get_args(), 1 );
161	}
162
163	while ( $timestamp = wp_next_scheduled( $hook, $args ) )
164		wp_unschedule_event( $timestamp, $hook, $args );
165}
166
167/**
168 * Retrieve the next timestamp for a cron event.
169 *
170 * @since 2.1.0
171 *
172 * @param string $hook Action hook to execute when cron is run.
173 * @param array $args Optional. Arguments to pass to the hook's callback function.
174 * @return bool|int The UNIX timestamp of the next time the scheduled event will occur.
175 */
176function wp_next_scheduled( $hook, $args = array() ) {
177	$crons = _get_cron_array();
178	$key = md5(serialize($args));
179	if ( empty($crons) )
180		return false;
181	foreach ( $crons as $timestamp => $cron ) {
182		if ( isset( $cron[$hook][$key] ) )
183			return $timestamp;
184	}
185	return false;
186}
187
188/**
189 * Send request to run cron through HTTP request that doesn't halt page loading.
190 *
191 * @since 2.1.0
192 *
193 * @return null Cron could not be spawned, because it is not needed to run.
194 */
195function spawn_cron( $local_time = 0 ) {
196
197	if ( ! $local_time )
198		$local_time = microtime( true );
199
200	if ( defined('DOING_CRON') || isset($_GET['doing_wp_cron']) )
201		return;
202
203	/*
204	* multiple processes on multiple web servers can run this code concurrently
205	* try to make this as atomic as possible by setting doing_cron switch
206	*/
207	$lock = get_transient('doing_cron');
208
209	if ( $lock > $local_time + 10*60 )
210		$lock = 0;
211
212	// don't run if another process is currently running it or more than once every 60 sec.
213	if ( $lock + WP_CRON_LOCK_TIMEOUT > $local_time )
214		return;
215
216	//sanity check
217	$crons = _get_cron_array();
218	if ( !is_array($crons) )
219		return;
220
221	$keys = array_keys( $crons );
222	if ( isset($keys[0]) && $keys[0] > $local_time )
223		return;
224
225	if ( defined('ALTERNATE_WP_CRON') && ALTERNATE_WP_CRON ) {
226		if ( !empty($_POST) || defined('DOING_AJAX') )
227			return;
228
229		$doing_wp_cron = sprintf( '%.22F', $local_time );
230		set_transient( 'doing_cron', $doing_wp_cron );
231
232		ob_start();
233		wp_redirect( add_query_arg('doing_wp_cron', $doing_wp_cron, stripslashes($_SERVER['REQUEST_URI'])) );
234		echo ' ';
235
236		// flush any buffers and send the headers
237		while ( @ob_end_flush() );
238		flush();
239
240		WP_DEBUG ? include_once( ABSPATH . 'wp-cron.php' ) : @include_once( ABSPATH . 'wp-cron.php' );
241		return;
242	}
243
244	$doing_wp_cron = sprintf( '%.22F', $local_time );
245	set_transient( 'doing_cron', $doing_wp_cron );
246
247	$cron_url = site_url( 'wp-cron.php?doing_wp_cron=' . $doing_wp_cron );
248	wp_remote_post( $cron_url, array( 'timeout' => 0.01, 'blocking' => false, 'sslverify' => apply_filters( 'https_local_ssl_verify', true ) ) );
249}
250
251/**
252 * Run scheduled callbacks or spawn cron for all scheduled events.
253 *
254 * @since 2.1.0
255 *
256 * @return null When doesn't need to run Cron.
257 */
258function wp_cron() {
259
260	// Prevent infinite loops caused by lack of wp-cron.php
261	if ( strpos($_SERVER['REQUEST_URI'], '/wp-cron.php') !== false || ( defined('DISABLE_WP_CRON') && DISABLE_WP_CRON ) )
262		return;
263
264	if ( false === $crons = _get_cron_array() )
265		return;
266
267	$local_time = microtime( true );
268	$keys = array_keys( $crons );
269	if ( isset($keys[0]) && $keys[0] > $local_time )
270		return;
271
272	$schedules = wp_get_schedules();
273	foreach ( $crons as $timestamp => $cronhooks ) {
274		if ( $timestamp > $local_time ) break;
275		foreach ( (array) $cronhooks as $hook => $args ) {
276			if ( isset($schedules[$hook]['callback']) && !call_user_func( $schedules[$hook]['callback'] ) )
277				continue;
278			spawn_cron( $local_time );
279			break 2;
280		}
281	}
282}
283
284/**
285 * Retrieve supported and filtered Cron recurrences.
286 *
287 * The supported recurrences are 'hourly' and 'daily'. A plugin may add more by
288 * hooking into the 'cron_schedules' filter. The filter accepts an array of
289 * arrays. The outer array has a key that is the name of the schedule or for
290 * example 'weekly'. The value is an array with two keys, one is 'interval' and
291 * the other is 'display'.
292 *
293 * The 'interval' is a number in seconds of when the cron job should run. So for
294 * 'hourly', the time is 3600 or 60*60. For weekly, the value would be
295 * 60*60*24*7 or 604800. The value of 'interval' would then be 604800.
296 *
297 * The 'display' is the description. For the 'weekly' key, the 'display' would
298 * be <code>__('Once Weekly')</code>.
299 *
300 * For your plugin, you will be passed an array. you can easily add your
301 * schedule by doing the following.
302 * <code>
303 * // filter parameter variable name is 'array'
304 *	$array['weekly'] = array(
305 *		'interval' => 604800,
306 *		'display' => __('Once Weekly')
307 *	);
308 * </code>
309 *
310 * @since 2.1.0
311 *
312 * @return array
313 */
314function wp_get_schedules() {
315	$schedules = array(
316		'hourly' => array( 'interval' => 3600, 'display' => __('Once Hourly') ),
317		'twicedaily' => array( 'interval' => 43200, 'display' => __('Twice Daily') ),
318		'daily' => array( 'interval' => 86400, 'display' => __('Once Daily') ),
319	);
320	return array_merge( apply_filters( 'cron_schedules', array() ), $schedules );
321}
322
323/**
324 * Retrieve Cron schedule for hook with arguments.
325 *
326 * @since 2.1.0
327 *
328 * @param string $hook Action hook to execute when cron is run.
329 * @param array $args Optional. Arguments to pass to the hook's callback function.
330 * @return string|bool False, if no schedule. Schedule on success.
331 */
332function wp_get_schedule($hook, $args = array()) {
333	$crons = _get_cron_array();
334	$key = md5(serialize($args));
335	if ( empty($crons) )
336		return false;
337	foreach ( $crons as $timestamp => $cron ) {
338		if ( isset( $cron[$hook][$key] ) )
339			return $cron[$hook][$key]['schedule'];
340	}
341	return false;
342}
343
344//
345// Private functions
346//
347
348/**
349 * Retrieve cron info array option.
350 *
351 * @since 2.1.0
352 * @access private
353 *
354 * @return array CRON info array.
355 */
356function _get_cron_array()  {
357	$cron = get_option('cron');
358	if ( ! is_array($cron) )
359		return false;
360
361	if ( !isset($cron['version']) )
362		$cron = _upgrade_cron_array($cron);
363
364	unset($cron['version']);
365
366	return $cron;
367}
368
369/**
370 * Updates the CRON option with the new CRON array.
371 *
372 * @since 2.1.0
373 * @access private
374 *
375 * @param array $cron Cron info array from {@link _get_cron_array()}.
376 */
377function _set_cron_array($cron) {
378	$cron['version'] = 2;
379	update_option( 'cron', $cron );
380}
381
382/**
383 * Upgrade a Cron info array.
384 *
385 * This function upgrades the Cron info array to version 2.
386 *
387 * @since 2.1.0
388 * @access private
389 *
390 * @param array $cron Cron info array from {@link _get_cron_array()}.
391 * @return array An upgraded Cron info array.
392 */
393function _upgrade_cron_array($cron) {
394	if ( isset($cron['version']) && 2 == $cron['version'])
395		return $cron;
396
397	$new_cron = array();
398
399	foreach ( (array) $cron as $timestamp => $hooks) {
400		foreach ( (array) $hooks as $hook => $args ) {
401			$key = md5(serialize($args['args']));
402			$new_cron[$timestamp][$hook][$key] = $args;
403		}
404	}
405
406	$new_cron['version'] = 2;
407	update_option( 'cron', $new_cron );
408	return $new_cron;
409}