Fix licensing serving through woo-sl-licensing.

woo-sl-licensing-fix.php

<?php

add_filter('WOOSL/API/get_downloadable_product_permission', function($permission, $download_id, $order_id) {
    global $wpdb;

    if (!$permission) {
        if (!function_exists('wcs_get_subscriptions_for_order')) {
            return $permission;
        }

        $sub_order = wcs_get_subscriptions_for_order($order_id);

        // if we don't have a subscription do regular
        if (empty($sub_order)) {
            return $permission;
        }

        // get subscription ids
        $sub_order_ids = array_keys($sub_order);

        // if we have some, get permission based on this order id
        if (!empty($sub_order_ids[0])) {
            $mysql_query = $wpdb->prepare("SELECT * FROM {$wpdb->prefix}woocommerce_downloadable_product_permissions
                            WHERE download_id = %s AND order_id = %d
                            ", $download_id, $sub_order_ids[0]);
                                                
            $permission = $wpdb->get_row( $mysql_query );
        }
    }

    return $permission;
}, 10, 3);