WooCommerce Webhook Custom Action Hook

webhook.php

<?php
/**
 * Plugin Name: Woo Custom Webhook
 * Plugin URI:  https://wpbeaches.com/send-full-product-details-over-woocommerce-webhook-action-hook/
 * Description: Custom WooCommerce Webhook Action
 * Author URI: https://github.com/woocommerce/woocommerce/issues/20336#issuecomment-829510702
 * Version: 0.1.0
 */


/**
 * Set the proper resource payload for a custom action webhook
 *
 * @param int $target_webhook_id
 * @param string $desired_resource 'order', 'product', 'coupon', or 'customer'
 */
function set_resource_for_webhook_payload_by_webhook_id($target_webhook_id, $desired_resource) {

    // Set the desired_resource payload for this webhook ('order', 'product', 'coupon', 'customer')
    add_filter('woocommerce_webhook_resource', function($resource, $webhook_id) use ($target_webhook_id, $desired_resource) {
        if($webhook_id == $target_webhook_id) {
            return $desired_resource;
        }
        return $resource;
    }, 10, 2);

    // Need to ensure our event (i.e., action) is seen as valid, as we've changed the default 'action.' prefix for the topic above
    add_filter('woocommerce_valid_webhook_events', function($valid_events) use ($target_webhook_id) {
        try {
            $topic = wc_get_webhook($target_webhook_id)->get_topic();

            list($resource, $event) = explode('.', $topic);

            if(!empty($event)) {
                $valid_events[] = $event;
            }

            return $valid_events;

        } catch (Exception $e) {
            return $valid_events;
        }
    }, 10);

}

// Change the Webhook ID to suit and data source of order, product, coupon or customer
add_action('init', function(){
    set_resource_for_webhook_payload_by_webhook_id( 1, 'order' );
});