Check if function called by cron job

Question

I have a function that I only want to run via a cron job. Is there a way I can check that a particular scheduled event is calling this function and not anything else?

Answer 1

WordPress has a constant DOING_CRON that helps us know we're doing the cron jobs or not. It's defined in wp-cron.php file.

So, you can check this constant in your code:

if ( defined( 'DOING_CRON' ) )
{
    // Do something
}

Answer 2

Just take a look at the »Cron API inspector«, that I wrote for question #18017. The plugin builds a table that shows on the shutdown-hook/the end of the page.

It uses the _get_cron_array() function to retrieve all registered & scheduled actions. Another useful function is wp_get_schedules(). The third way is calling the underlying data for _get_cron_array() directly, by calling get_option( 'cron' ); - it's still better to use the default API functions from WP core.

If you want to know if you're currently inside a Cron Job, then you can check defined( 'DOING_CRON' ) AND DOING_CRON.

Answer 3

I'm not studies development (I'm just an enthusiast) but I think you may add a add_action to the event

It's just a resume...

//to the event
if(your_condition)
{
    add_action('original_event_to_hook', 'your_scheduled');
}

function your_scheduled()
{
    //create a param here
    //And shedule your function with arg
    wp_schedule_event(time(), 'hourly', 'your_function', array('param_1' => value));
}

function your_function($args){

   $verification = $args['param_1'];
   if($verification)
   {
      //OK
      //Eventually delete this schedule with this specific arg
   }
}

To retrieve a list of your cron "your_function" where have this arg

     //Get a filtered list of cron hooks 
        function kw_filter_crons_hooks($hooks = false, $args = false)
        {
            $crons = get_option('cron');

            if (!$crons)
            {
                $crons[0] = NULL;
            }

            $filter = array();
            $cronlist = array();
            $schedule = array();

            foreach($crons as $timestamp => $cron)
            {
                //@param $hooks = string 'schedule'
                //@param $args = false
                //Return an array of cron task sheduled
                $schedule[] = $cron;

                if(!$schedule && $hooks == 'schedule' && $args == false)
                {
                    $schedule[0] = NULL;
                }

                foreach($hooks as $hook)
                {
                    if(isset($cron[$hook]))
                    {
                        //@param $hooks = array($hook);
                        //@param $args = false
                        //Return an array of cron task sheduled
                        $cronlist[] = $cron;

                        if(!$cronlist && is_array($hooks) && $args == false)
                        {
                            $cronlist[0] = NULL;
                        }

                        if(!empty($args))
                        {
                            foreach($cronlist as $key => $value)
                            {
                                foreach($value as $k => $v)
                                {
                                    foreach($v as $x => $y)
                                    {
                                        foreach($args as $arg => $val)
                                        {
                                            if ($y['args'][$arg] == $val)
                                            {
                                                //@param $hooks = array($hook);
                                                //@param $args = array($arg);
                                                //Return an array of cron task specified filtered by arg
                                                $filter[$x] = $y;
                                                if(!$filter && is_array($hooks) && is_array($args))
                                                {
                                                    $filter[0] = NULL;
                                                }
                                            }
                                        }
                                    }
                                }
                            }
                        }
                    }
                }
            }


            if(is_array($hooks) && $args === false && $cronlist)
            {
                return $cronlist;
            }
            else if(is_array($hooks) && is_array($args) && $filter)
            {
                return $filter;
            }
            else if($hooks === 'schedule' && $args === false && $schedule)
            {
                return $schedule;
            }
            else if($hooks === false && $args === false && $crons)
            {
                return $crons;
            }
            else
            {
                return false;
            }
        }

//Usage
    $cron_filtered = kw_filter_crons_hooks(array('your_function'), array('param_1' => value));
    var_dump($cron_filtered);