Schedule cron don't work

Question

I try to set up a cronjob. It seems like it run the le_schedule function but not the le_do_this function. I also tried some cronjob plugins, some says it runs and some says it fails.

In this case it will try to get a file and save it but it doesn't. Why doesn't this work?

add_action( 'wp', 'le_schedule' );
add_action( 'le_event', 'le_do_this' );

function le_schedule() {
    if ( ! wp_next_scheduled( 'le_event' ) ) {
        wp_schedule_event( time(), 'daily', 'le_event');
    }
}

function le_do_this() {
    $response = wp_remote_get('http://www.example.com/file.txt');
    if( ! is_wp_error( $response ) ) {
        $body = wp_remote_retrieve_body($response);
        if( ! empty( $body ) ) {
            $put = get_template_directory() . '/cache/cache.txt';
            file_put_contents( $put, $body );
        }
    }
}

wp_clear_scheduled_hook( 'le_event' );
wp_clear_scheduled_hook( 'le_do_this' );

I clear the schedule to be able to run fresh on every pageload.

Answer 1

You shouldn't call wp_clear_scheduled_hook on every page load, because then you're always restarting your wp-cron shcedule, with your current setup.

Additionally this call:

wp_clear_scheduled_hook( 'le_do_this' );

doesn't make any difference, since le_do_this isn't a hook name in your setup.

You could try for example this test plugin:

<?php
/**
 * Plugin Name: Daily WP-Cron
 * Description: Call the my_daily_cron_script() function daily, if it exists.
 */

add_action( 'mydailyevent', function()
{
    // Our script:
    if( function_exists( 'my_daily_cron_script' ) )
        my_daily_cron_script();
});

register_activation_hook( __FILE__, function()            
{ 
    // Start the cron job:
    wp_schedule_event( time(), 'daily', 'mydailyevent' );
});

register_deactivation_hook( __FILE__, function()
{
    // Stop the cron job:
    wp_clear_scheduled_hook( 'mydailyevent' );
});

where you have to define the my_daily_cron_script() function to your needs.

There's a warning in the Codex on wp_schedule_event:

The name of an action hook to execute. For some reason there seems to be a problem on some systems where the hook must not contain underscores or uppercase characters.

so let's just use mydailyevent as our hook name, instead of my_daily_event, just in case.