­ ­ ­ ­ ­ ­ ­ ­ ­ ­ ­ ­ ­ ­ ­ ­ ­ ­ _queue_id = $queue_id; $this->_queue_key = 'wpo_queue_' . $this->_queue_id; $this->_lock = new Updraft_Semaphore_3_0($queue_id); // loggers for semaphore if (!empty(WP_Optimize()->wpo_loggers())) { $this->_lock->set_loggers(WP_Optimize()->wpo_loggers()); } $this->_logger = new Updraft_PHP_Logger(); } /** * Lock queue. * * @return bool */ public function lock() { $this->log('WP_Optimize_Tasks_Queue->lock()'); $this->_locked = $this->_lock->lock(); return $this->_locked; } /** * Unlock queue. */ public function unlock() { $this->log('WP_Optimize_Tasks_Queue->unlock()'); $this->_lock->release(); $this->_locked = null; } /** * Wait until queue will free. */ public function wait() { if ($this->is_locked()) return; $this->log('WP_Optimize_Tasks_Queue->wait()'); $time_start = microtime(true); $time_limit = 5; // limit time seconds. while (false === $this->lock() && ($time_limit > (microtime(true) - $time_start))) { $this->sleep(0.5); } } /** * Returns true if queue is locked. * * @return bool */ public function is_locked() { return (null === $this->_locked || true === $this->_locked); } /** * Return instance of WP_Optimize_Tasks_Queue. * * @param string $queue_id * @return WP_Optimize_Tasks_Queue */ public static function this($queue_id = 'queue') { if (!array_key_exists($queue_id, self::$_instances)) { self::$_instances[$queue_id] = new WP_Optimize_Tasks_Queue($queue_id); self::$_instances[$queue_id]->load(); } return self::$_instances[$queue_id]; } /** * Delete queue form database. */ public function delete_queue() { global $wpdb; $this->log('WP_Optimize_Tasks_Queue->delete_queue()'); // disable action if queue is not locked. if (!$this->is_locked()) return; $tasks_ids = $wpdb->get_col($wpdb->prepare("SELECT DISTINCT(tm.task_id) FROM `{$wpdb->base_prefix}tm_taskmeta` tm WHERE tm.meta_key='queue_id' AND tm.meta_value=%s", $this->_queue_id)); if (empty($tasks_ids)) return; $tasks_ids = join(',', $tasks_ids); $wpdb->query("DELETE t, tm FROM `{$wpdb->base_prefix}tm_tasks` t JOIN `{$wpdb->base_prefix}tm_taskmeta` tm ON t.id = tm.task_id WHERE t.id IN ($tasks_ids)"); // phpcs:ignore WordPress.DB.PreparedSQL.InterpolatedNotPrepared -- Safe, tasks_ids are comma separated integers } public function clear_queue() { $this->log('WP_Optimize_Tasks_Queue->clear_queue()'); $this->_queue = array(); } /** * Returns tru if queue is empty. * * @return bool */ public function is_empty() { return (0 == $this->length()); } /** * Returns count of tasks in queue. * * @return int */ public function length() { return count($this->_queue); } /** * Add task to queue. * * @param WP_Optimize_Queue_Task $task */ public function add_task($task) { $this->log('WP_Optimize_Tasks_Queue->add_task({task})', array('task' => $task->get_info())); // check if queue locked unsuccessfully, you don't need lock queue. if (!$this->is_locked()) return; $task->set_queue_id($this->_queue_id); // $task->save(); $this->_queue[] = $task; } /** * Load queue tasks form database. */ public function load() { global $wpdb; $this->log('WP_Optimize_Tasks_Queue->load()'); // load tasks info from database. $tasks = $wpdb->get_results("SELECT task_id, meta_key, meta_value FROM `{$wpdb->base_prefix}tm_taskmeta` t ORDER BY task_id", ARRAY_A); $_tasks = array(); // arrange tasks info. foreach ($tasks as $info) { $task_id = $info['task_id']; if (!array_key_exists($task_id, $_tasks)) $_tasks[$task_id] = array(); if ('task' === $info['meta_key']) { $_info = WP_Optimize_Utils::maybe_unserialize($info['meta_value']); if (is_array($_info)) { foreach ($_info as $key => $value) { $_tasks[$task_id][$key] = $value; } } } else { $_tasks[$task_id][$info['meta_key']] = WP_Optimize_Utils::maybe_unserialize($info['meta_value']); } } $this->_queue = array(); // build queue. foreach ($_tasks as $task_id => $info) { // if unsupported task information then don't create task. if (empty($info['task'])) continue; $task = new WP_Optimize_Queue_Task($info['task'], $info['params'], $info['callback'], $info['priority']); $task->set_id($task_id); $task->set_queue_id($this->_queue_id); $this->_queue[] = $task; } // sort queue tasks by priority usort($this->_queue, array($this, 'cmp_order')); } /** * Compare function for ordering tasks in queue by priority. * * @param WP_Optimize_Queue_Task $task_a * @param WP_Optimize_Queue_Task $task_b * @return int */ public function cmp_order($task_a, $task_b) { if ($task_a->priority == $task_b->priority) { return ($task_a->get_id() < $task_b->get_id()) ? -1 : 1; } return ($task_a->priority < $task_b->priority) ? -1 : 1; } /** * Save tasks to database and clear queue. */ public function flush() { if (!$this->is_locked()) return; $this->log('WP_Optimize_Tasks_Queue->flush()'); // save tasks those not exists in DB. foreach ($this->_queue as $task) { if (!$task->get_id()) $task->save(); } // clear queue variable. $this->clear_queue(); } /** * Returns next task from the queue. * * @return bool|WP_Optimize_Queue_Task */ public function get_next_task() { // global $wpdb; $this->log('WP_Optimize_Tasks_Queue->get_next_task()'); // Find task in queue. if (empty($this->_queue)) return false; $next_task_i = false; foreach ($this->_queue as $i => $task) { if (false === $next_task_i || $this->_queue[$next_task_i]->priority > $task->priority) { $next_task_i = $i; } } // $task = $wpdb->get_results($wpdb->prepare("SELECT t.task_id FROM `{$wpdb->base_prefix}tm_tasks` t JOIN `{$wpdb->base_prefix}tm_taskmeta` tm ON t.task_id = tm.task_id WHERE t.status='active' AND tm.meta_key='priority' AND t.task_id IN (SELECT DISTINCT(tm.task_id) FROM {$wpdb->base_prefix}tm_taskmeta tm WHERE tm.meta_key='queue_id' AND tm.meta_value=%s) ORDER BY tm.meta_value, t.task_id LIMIT 1", $this->_queue_id)); if (false !== $next_task_i) { $next_task = $this->_queue[$next_task_i]; unset($this->_queue[$next_task_i]); return $next_task; } return false; } /** * Do next task from queue. */ public function do_next_task() { $this->log('WP_Optimize_Tasks_Queue->do_next_task()'); // disable action if queue is not locked. if (!$this->is_locked()) { // short sleep before next try. $this->sleep(0.5); $this->lock(); return; } $task = $this->get_next_task(); // do task. if (is_object($task) && is_a($task, 'WP_Optimize_Queue_Task')) { $this->log('WP_Optimize_Tasks_Queue->run({task})', array('task' => $task->get_info())); $task->run(); $task->delete_meta(); $task->delete(); } } /** * Save meta value for queue. * * @param string $name * @param mixed $value */ public function set_meta($name, $value) { $this->_meta[$name] = $value; } /** * Return meta value. * * @param string $name * @return mixed|null */ public function get_meta($name) { if (array_key_exists($name, $this->_meta)) return $this->_meta[$name]; return null; } /** * Sleep for $seconds. * * @param float $seconds */ private function sleep($seconds) { $second = 1000000; // microseconds in second. usleep(floor($seconds * $second)); } /** * Log message into PHP log. * * @param string $message * @param array $context */ private function log($message, $context = array()) { if (defined('WP_OPTIMIZE_UNUSED_IMAGES_LOG') && WP_OPTIMIZE_UNUSED_IMAGES_LOG) { $this->_logger->debug($message, $context); } } }