foreach ( array( 'update', 'create', 'delete' ) as $batch_type ) {
            if ( ! empty( $items[ $batch_type ] ) ) {
                $injected_items = array();
                foreach ( $items[ $batch_type ] as $item ) {
                    $injected_items[] = is_array( $item ) ? array_merge( array( 'product_id' => $product_id ), $item ) : $item;