Magento 2 copy value from custom attribute to order item

Question

I have created a custom attribute for products. And I have also created an extra column in sales_order_item. How can I copy the value from this custom attribute to the new column in sales_order_item when an order is placed?

Answer 1

You can use plugin to add custom attribute to sales_order_item when order is placed. create a di.xml on under etc/di.xml.

<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:ObjectManager/etc/config.xsd" >
 <type name='Magento\Quote\Model\Quote\Item\ToOrderItem'>
 <plugin name='AddOrderItemPlugin' type='Vendorname\Module\Plugin\Model\Quote\Item\ToOrderItem' sortOrder='99'/>
 </type>
</config>

Now add a file Vendorname\Module\Plugin\Model\Quote\Item\ToOrderItem.php

<?php 
namespace Vendorname\Modulename\Plugin\Model\Quote\Item;
 class ToOrderItem {
 /**
 *
 * @var type \Magento\Catalog\Model\Product
 */
 protected $productRepository;
 /**
 * @param \Magento\Catalog\Model\Product $productRepository 
 */
 public function __construct(
 \Magento\Catalog\Model\Product $productRepository 
 ) {
 $this->productRepository = $productRepository;
 }
 /**
 * 
 * @param \Magento\Quote\Model\Quote\Item\ToOrderItem $subject
 * @param \Vendorname\Modulename\Plugin\Model\Quote\Item\callable $proceed
 * @param \Magento\Quote\Model\Quote\Item\AbstractItem $item
 * @param type $additional
 * @return type
 */
 public function aroundConvert(
 \Magento\Quote\Model\Quote\Item\ToOrderItem $subject, callable $proceed, \Magento\Quote\Model\Quote\Item\AbstractItem $item, $additional = []
 ) {
 $orderItem = $proceed($item, $additional);
 $productId = $item->getProduct()->getId();
 $product = $this->productRepository->load($productId);
 $supplier = $product->getSuppliers();//my custom product attribute
 $orderItem->setSupplierId($supplier);//saving into orde item in `supplier_id` column
 return $orderItem;
 }
 }