Add Product Custom Field in Listing Returning WooCommerce Rest API (Version WC 3.7.1) - Adicionar campo personalizado do produto na listagem retornando API Rest do WooCommerce (Versão WC 3.7.1)

functions.php

<?php 

/*
* Add Product Custom Field in Listing Returning WooCommerce Rest API (Version WC 3.7.1)
* Adicionar campo personalizado do produto na listagem retornando API Rest do WooCommerce (Versão WC 3.7.1)
*/

function wc_add_rest_line_items( $response, $post, $request ) {
	
	foreach( $response->data['line_items'] as $item_id => $line_item ) {
		if ( ! empty( $line_item['product_id'] ) ) {
			$product_id = ! empty( $line_item['variation_id'] ) ? $line_item['variation_id'] : $line_item['product_id'];
			$meta_key = 'Assigned Field Name';
			$meta_key_selected = 'Selected Field Name';

			$response->data['line_items'][ $item_id ][ $meta_key ] =  get_post_meta( $product_id, $meta_key_selected, true );
		}
	}
	
	return $response;	
}

add_filter( 'woocommerce_rest_prepare_shop_order_object', 'wc_add_rest_line_items', 10, 3 );