/** * WP Async Request * * @package WP-Background-Processing */ if ( ! class_exists( 'WP_Async_Request' ) ) { /** * Abstract WP_Async_Request class. * * @abstract */ abstract class WP_Async_Request { /** * Prefix * * (default value: 'wp') * * @var string * @access protected */ protected $prefix = 'wp'; /** * Action * * (default value: 'async_request') * * @var string * @access protected */ protected $action = 'async_request'; /** * Identifier * * @var mixed * @access protected */ protected $identifier; /** * Data * * (default value: array()) * * @var array * @access protected */ protected $data = array(); /** * Initiate new async request */ public function __construct() { $this->identifier = $this->prefix . '_' . $this->action; add_action( 'wp_ajax_' . $this->identifier, array( $this, 'maybe_handle' ) ); add_action( 'wp_ajax_nopriv_' . $this->identifier, array( $this, 'maybe_handle' ) ); } /** * Set data used during the request * * @param array $data Data. * * @return $this */ public function data( $data ) { $this->data = $data; return $this; } /** * Dispatch the async request * * @return array|WP_Error */ public function dispatch() { $url = add_query_arg( $this->get_query_args(), $this->get_query_url() ); $args = $this->get_post_args(); return wp_remote_post( esc_url_raw( $url ), $args ); } /** * Get query args * * @return array */ protected function get_query_args() { if ( property_exists( $this, 'query_args' ) ) { return $this->query_args; } return array( 'action' => $this->identifier, 'nonce' => wp_create_nonce( $this->identifier ), ); } /** * Get query URL * * @return string */ protected function get_query_url() { if ( property_exists( $this, 'query_url' ) ) { return $this->query_url; } return admin_url( 'admin-ajax.php' ); } /** * Get post args * * @return array */ protected function get_post_args() { if ( property_exists( $this, 'post_args' ) ) { return $this->post_args; } return array( 'timeout' => 0.01, 'blocking' => false, 'body' => $this->data, 'cookies' => $_COOKIE, 'sslverify' => apply_filters( 'https_local_ssl_verify', false ), ); } /** * Maybe handle * * Check for correct nonce and pass to handler. */ public function maybe_handle() { // Don't lock up other requests while processing session_write_close(); check_ajax_referer( $this->identifier, 'nonce' ); $this->handle(); wp_die(); } /** * Handle * * Override this method to perform any actions required * during the async request. */ abstract protected function handle(); } } /** * GF Background Process * * Based on WP_Background_Process * https://github.com/A5hleyRich/wp-background-processing/blob/master/classes/wp-background-process.php */ if ( ! class_exists( 'GF_Background_Process' ) ) { /** * Abstract GF_Background_Process class. * * @abstract * @extends WP_Async_Request */ abstract class GF_Background_Process extends WP_Async_Request { /** * Action * * (default value: 'background_process') * * @var string * @access protected */ protected $action = 'background_process'; /** * Start time of current process. * * (default value: 0) * * @var int * @access protected */ protected $start_time = 0; /** * Cron_hook_identifier * * @var mixed * @access protected */ protected $cron_hook_identifier; /** * Cron_interval_identifier * * @var mixed * @access protected */ protected $cron_interval_identifier; /** * Initiate new background process */ public function __construct() { parent::__construct(); $this->cron_hook_identifier = $this->identifier . '_cron'; $this->cron_interval_identifier = $this->identifier . '_cron_interval'; add_action( $this->cron_hook_identifier, array( $this, 'handle_cron_healthcheck' ) ); add_filter( 'cron_schedules', array( $this, 'schedule_cron_healthcheck' ) ); } /** * Dispatch * * @access public */ public function dispatch() { // Schedule the cron healthcheck. $this->schedule_event(); // Perform remote post. return parent::dispatch(); } /** * Push to queue * * @param mixed $data Data. * * @return $this */ public function push_to_queue( $data ) { $this->data[] = $data; return $this; } /** * Save queue * * @return $this */ public function save() { $key = $this->generate_key(); if ( ! empty( $this->data ) ) { update_site_option( $key, $this->data ); } return $this; } /** * Update queue * * @param string $key Key. * @param array $data Data. * * @return $this */ public function update( $key, $data ) { if ( ! empty( $data ) ) { update_site_option( $key, $data ); } return $this; } /** * Delete queue * * @param string $key Key. * * @return $this */ public function delete( $key ) { delete_site_option( $key ); return $this; } /** * Generate key * * Generates a unique key based on microtime. Queue items are * given a unique key so that they can be merged upon save. * * @param int $length Length. * * @return string */ protected function generate_key( $length = 64 ) { $unique = md5( microtime() . rand() ); $prepend = $this->identifier . '_batch_'; return substr( $prepend . $unique, 0, $length ); } /** * Maybe process queue * * Checks whether data exists within the queue and that * the process is not already running. */ public function maybe_handle() { // Don't lock up other requests while processing session_write_close(); if ( $this->is_process_running() ) { // Background process already running. wp_die(); } if ( $this->is_queue_empty() ) { // No data to process. wp_die(); } check_ajax_referer( $this->identifier, 'nonce' ); $this->handle(); wp_die(); } /** * Is queue empty * * @return bool */ protected function is_queue_empty() { global $wpdb; $table = $wpdb->options; $column = 'option_name'; if ( is_multisite() ) { $table = $wpdb->sitemeta; $column = 'meta_key'; } $key = $this->identifier . '_batch_%'; $count = $wpdb->get_var( $wpdb->prepare( " SELECT COUNT(*) FROM {$table} WHERE {$column} LIKE %s ", $key ) ); return ( $count > 0 ) ? false : true; } /** * Is process running * * Check whether the current process is already running * in a background process. */ protected function is_process_running() { if ( get_site_transient( $this->identifier . '_process_lock' ) ) { // Process already running. return true; } return false; } /** * Lock process * * Lock the process so that multiple instances can't run simultaneously. * Override if applicable, but the duration should be greater than that * defined in the time_exceeded() method. */ protected function lock_process() { $this->start_time = time(); // Set start time of current process. $lock_duration = ( property_exists( $this, 'queue_lock_time' ) ) ? $this->queue_lock_time : 60; // 1 minute $lock_duration = apply_filters( $this->identifier . '_queue_lock_time', $lock_duration ); set_site_transient( $this->identifier . '_process_lock', microtime(), $lock_duration ); } /** * Unlock process * * Unlock the process so that other instances can spawn. * * @return $this */ protected function unlock_process() { delete_site_transient( $this->identifier . '_process_lock' ); return $this; } /** * Get batch * * @return stdClass Return the first batch from the queue */ protected function get_batch() { global $wpdb; $table = $wpdb->options; $column = 'option_name'; $key_column = 'option_id'; $value_column = 'option_value'; if ( is_multisite() ) { $table = $wpdb->sitemeta; $column = 'meta_key'; $key_column = 'meta_id'; $value_column = 'meta_value'; } $key = $this->identifier . '_batch_%'; $query = $wpdb->get_row( $wpdb->prepare( " SELECT * FROM {$table} WHERE {$column} LIKE %s ORDER BY {$key_column} ASC LIMIT 1 ", $key ) ); $batch = new stdClass(); $batch->key = $query->$column; $batch->data = maybe_unserialize( $query->$value_column ); return $batch; } /** * Handle * * Pass each queue item to the task handler, while remaining * within server memory and time limit constraints. */ protected function handle() { $this->lock_process(); do { $batch = $this->get_batch(); foreach ( $batch->data as $key => $value ) { $task = $this->task( $value ); if ( false !== $task ) { $batch->data[ $key ] = $task; } else { unset( $batch->data[ $key ] ); } if ( $this->time_exceeded() || $this->memory_exceeded() ) { // Batch limits reached. break; } } // Update or delete current batch. if ( ! empty( $batch->data ) ) { $this->update( $batch->key, $batch->data ); } else { $this->delete( $batch->key ); } } while ( ! $this->time_exceeded() && ! $this->memory_exceeded() && ! $this->is_queue_empty() ); $this->unlock_process(); // Start next batch or complete process. if ( ! $this->is_queue_empty() ) { $this->dispatch(); } else { $this->complete(); } } /** * Memory exceeded * * Ensures the batch process never exceeds 90% * of the maximum WordPress memory. * * @return bool */ protected function memory_exceeded() { $memory_limit = $this->get_memory_limit() * 0.9; // 90% of max memory $current_memory = memory_get_usage( true ); $return = false; if ( $current_memory >= $memory_limit ) { $return = true; } return apply_filters( $this->identifier . '_memory_exceeded', $return ); } /** * Get memory limit * * @return int */ protected function get_memory_limit() { if ( function_exists( 'ini_get' ) ) { $memory_limit = ini_get( 'memory_limit' ); } else { // Sensible default. $memory_limit = '128M'; } if ( ! $memory_limit || -1 === $memory_limit ) { // Unlimited, set to 32GB. $memory_limit = '32000M'; } return intval( $memory_limit ) * 1024 * 1024; } /** * Time exceeded. * * Ensures the batch never exceeds a sensible time limit. * A timeout limit of 30s is common on shared hosting. * * @return bool */ protected function time_exceeded() { $finish = $this->start_time + apply_filters( $this->identifier . '_default_time_limit', 20 ); // 20 seconds $return = false; if ( time() >= $finish ) { $return = true; } return apply_filters( $this->identifier . '_time_exceeded', $return ); } /** * Complete. * * Override if applicable, but ensure that the below actions are * performed, or, call parent::complete(). */ protected function complete() { // Unschedule the cron healthcheck. $this->clear_scheduled_event(); } /** * Schedule cron healthcheck * * @access public * @param mixed $schedules Schedules. * @return mixed */ public function schedule_cron_healthcheck( $schedules ) { $interval = apply_filters( $this->identifier . '_cron_interval', 5 ); if ( property_exists( $this, 'cron_interval' ) ) { $interval = apply_filters( $this->identifier . '_cron_interval', $this->cron_interval_identifier ); } // Adds every 5 minutes to the existing schedules. $schedules[ $this->identifier . '_cron_interval' ] = array( 'interval' => MINUTE_IN_SECONDS * $interval, 'display' => sprintf( __( 'Every %d Minutes', 'gravityforms' ), $interval ), ); return $schedules; } /** * Handle cron healthcheck * * Restart the background process if not already running * and data exists in the queue. */ public function handle_cron_healthcheck() { if ( $this->is_process_running() ) { // Background process already running. exit; } if ( $this->is_queue_empty() ) { // No data to process. $this->clear_scheduled_event(); exit; } $this->handle(); exit; } /** * Schedule event */ protected function schedule_event() { if ( ! wp_next_scheduled( $this->cron_hook_identifier ) ) { wp_schedule_event( time(), $this->cron_interval_identifier, $this->cron_hook_identifier ); } } /** * Clear scheduled event */ protected function clear_scheduled_event() { $timestamp = wp_next_scheduled( $this->cron_hook_identifier ); if ( $timestamp ) { wp_unschedule_event( $timestamp, $this->cron_hook_identifier ); } } /** * Cancel Process * * Stop processing queue items, clear cronjob and delete batch. * */ public function cancel_process() { if ( ! $this->is_queue_empty() ) { $batch = $this->get_batch(); $this->delete( $batch->key ); wp_clear_scheduled_hook( $this->cron_hook_identifier ); } } /** * Task * * Override this method to perform any actions required on each * queue item. Return the modified item for further processing * in the next pass through. Or, return false to remove the * item from the queue. * * @param mixed $item Queue item to iterate over. * * @return mixed */ abstract protected function task( $item ); } }