HOw to create more than one extension attribute and how to set data init magento 2.3

Question

How to set the data in the extension attribute which i created and how to create more the one extension attribute in single module. My Following code is in below link.

URL : My Following code structure

Thanks in Advance :)

Answer 1

Let's assume that you have three fields then you to add like at

Sm\OrderFeedback\etc\extension_attributes.xml

<?xml version="1.0"?>
<!-- File: app/code/Sm/OrderFeedback/etc/extension_attributes.xml -->
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xsi:noNamespaceSchemaLocation="urn:magento:framework:Api/etc/extension_attributes.xsd">
    <extension_attributes for="Magento\Sales\Api\Data\OrderInterface">
        <attribute code="customer_feedback" type="string" />
        <attribute code="customfieldone" type="string" /> <!--assume that field type string-->
        <attribute code="customfieldtwo" type="int" /> <!--assume that field type integer-->
    </extension_attributes>
</config>

Add customfieldone,customfieldtwo to Sm\OrderFeedback\Plugin\OrderRepositoryPlugin.php for save using before plugin on Magento\Sales\Api\OrderRepositoryInterface:save.

<?php
/* File: app/code/Sm/OrderFeedback/Plugin/OrderRepositoryPlugin.php */

namespace Sm\OrderFeedback\Plugin;

use Magento\Sales\Api\Data\OrderExtensionFactory;
use Magento\Sales\Api\Data\OrderExtensionInterface;
use Magento\Sales\Api\Data\OrderInterface;
use Magento\Sales\Api\Data\OrderSearchResultInterface;
use Magento\Sales\Api\OrderRepositoryInterface;

/**
 * Class OrderRepositoryPlugin
 */
class OrderRepositoryPlugin
{
    /**
     * Order feedback field name
     */
    const FIELD_NAME = 'customer_feedback';

    /**
     * Order Extension Attributes Factory
     *
     * @var OrderExtensionFactory
     */
    protected $extensionFactory;

    /**
     * OrderRepositoryPlugin constructor
     *
     * @param OrderExtensionFactory $extensionFactory
     */
    public function __construct(OrderExtensionFactory $extensionFactory)
    {
        $this->extensionFactory = $extensionFactory;
    }

    /**
     * Add "customer_feedback" extension attribute to order data object to make it accessible in API data
     *
     * @param OrderRepositoryInterface $subject
     * @param OrderInterface $order
     *
     * @return OrderInterface
     */
    public function afterGet(OrderRepositoryInterface $subject, OrderInterface $order)
    {
        $customerFeedback = $order->getData(self::FIELD_NAME);
        $extensionAttributes = $order->getExtensionAttributes();
        $extensionAttributes = $extensionAttributes ? $extensionAttributes : $this->extensionFactory->create();
        $extensionAttributes->setCustomerFeedback($customerFeedback);
        $order->setExtensionAttributes($extensionAttributes);

        return $order;
    }

    /**
     * Add "customer_feedback" extension attribute to order data object to make it accessible in API data
     *
     * @param OrderRepositoryInterface $subject
     * @param OrderSearchResultInterface $searchResult
     *
     * @return OrderSearchResultInterface
     */
    public function afterGetList(OrderRepositoryInterface $subject, OrderSearchResultInterface $searchResult)
    {
        $orders = $searchResult->getItems();

        foreach ($orders as $order) {
            $customerFeedback = $order->getData(self::FIELD_NAME);
            $extensionAttributes = $order->getExtensionAttributes();
            $extensionAttributes = $extensionAttributes ? $extensionAttributes : $this->extensionFactory->create();
            $extensionAttributes->setCustomerFeedback($customerFeedback);
            $order->setExtensionAttributes($extensionAttributes);
        }

        return $searchResult;
    }

    /** save fields**/
    public function beforeSave(
      OrderRepositoryInterface $subject,  
      OrderInterface $order
    ){
         $extensionAttributes = $order->getExtensionAttributes();

         if($extensionAttributes !== null){
            $customfieldOne =$order->getExtensionAttributes()->getCustomfieldone();
            $customfieldtwo =$order->getExtensionAttributes()->getCustomfieldtwo();
            if($customfieldOne !== null) {
               $order->setData('customfieldone',$customfieldOne);
            }
            if($customfieldtwo !== null) {
                $order->setData('customfieldtwo',$customfieldtwo);
            }            
         }
         return $order;
    }
}

If you set custom field value using setter function $order->setData('fieldName',$Fieldvalue) on beforeSave() plugin method to order object and Resource mode automatically save to sale_order table like $order->setData('customfieldtwo',$customfieldtwo);

To better understand how extension attribute will implement on Magento 2 ,checkout the blog https://store.fooman.co.nz/blog/an-introduction-to-extension-attributes.html