understanding wp_next_scheduled

Question

I have a function that I've been attempting to get to work with wp_schedule_event. The function sends a notification to the admin. I see the event get added to the wp cron event list, but it never runs the function.

Function as follows:

<?php

function send_booking_expiration_notification(){
  // do woocomerce booking stuff... then send email.
 wp_mail($to, $subject, $message, $headers);
}

// Schedule the send_booking_expiration_notification() function to run daily at midnight
if ( ! wp_next_scheduled( 'send_booking_expiration_hook' ) ) {
    wp_schedule_event( strtotime( '12pm' ), 'hourly', 'send_booking_expiration_hook' );
}
add_action( 'send_booking_expiration_hook', 'send_booking_expiration_notification' );

?>

Am I misunderstanding scope or hooks. I've added the add_action above the function and still no dice. I can call the function and the have confirmed the function works and send email, but something with the cron isn't working.

Answer 1

You're probably attempting to add this too early. Wait for init.

add_action(
    'init',
    function () {
        if ( ! wp_next_scheduled( 'send_booking_expiration_hook' ) ) {
            wp_schedule_event( strtotime( '12pm' ), 'hourly', 'send_booking_expiration_hook' );
        }
    }
);