Replacing the Deprecated "woocommerce_add_order_item_meta" Hook in WooCommerce

The deprecated "woocommerce_add_order_item_meta" hook has been a commonly used method for adding custom meta to order items. With the release of WooCommerce 2.3.7, this hook is now deprecated, leaving developers searching for an alternative.

Replacement Hook: woocommerce_checkout_create_order_line_item

Since WooCommerce 3, a new CRUD (Create, Read, Update, Delete) system has been introduced, which includes new setters and getters methods. The replacement hook for "woocommerce_add_order_item_meta" is woocommerce_checkout_create_order_line_item.

woocommerce_checkout_create_order_line_item Arguments:

This hook provides four arguments:

• $item: An instance of the new WC_Order_Item_Product class
• $cart_item_key: The unique hash key of the cart item
• $values: The cart item data
• $order: An instance of the WC_Order object

Usage of woocommerce_checkout_create_order_line_item:

To add custom meta to order items using this hook, you can use the following updated code:

add_action( 'woocommerce_checkout_create_order_line_item', 'custom_checkout_create_order_line_item', 20, 4 );
function custom_checkout_create_order_line_item( $item, $cart_item_key, $values, $order ) {
    // Update order item meta using the WC_Data update_meta_data() method
    $item->update_meta_data( 'meta_key1', $custom_field_value );
}

Alternative: Using the Old Way

While the woocommerce_checkout_create_order_line_item hook is the recommended replacement, you can also still use the deprecated "woocommerce_add_order_item_meta" hook if needed. However, it is important to note that this hook is deprecated and may be removed in future versions of WooCommerce.

add_action( 'woocommerce_add_order_item_meta', 'custom_add_order_item_meta', 20, 3 );
function custom_add_order_item_meta( $item_id, $values, $cart_item_key ) {
    // Update order item meta using wc_add_order_item_meta()
    wc_add_order_item_meta( $item_id, 'meta_key1', $custom_field_value );
}

Conclusion

The woocommerce_checkout_create_order_line_item hook is the recommended replacement for the deprecated "woocommerce_add_order_item_meta" hook when using WooCommerce 3 and newer. It provides the same functionality and aligns with the new CRUD system introduced in that version.