Magento 2 :How to override Magento\Sales\Model\Order\Email\Sender.php model?

Question

Is their any way we can override Magento\Sales\Model\Order\Email\Sender.php model in magento 2 module ?

I have created below files

di.xml

<?xml version="1.0"?>
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:ObjectManager/etc/config.xsd">
    <preference for="Magento\Sales\Model\Order\Email\Sender" type="Mod\Sales\Model\Order\Email\Sender" />
</config>


app/code/Mod/Sales/Model/Order/Email/Sender.php

I have added log in

protected function prepareTemplate(Order $order)
    {
        $writer = new \Zend\Log\Writer\Stream(BP . '/var/log/prepareTemplate.log');
        $logger = new \Zend\Log\Logger();
        $logger->addWriter($writer);
        $logger->info('$templateId');

but log did not generated.

Any thoughts ?

Answer 1

Update

Updated the Observer Class

---

If you want to override the model Magento\Sales\Model\Order\Email\Sender\OrderSender just to extend the method prepareTemplate in order to add or modify email order template variables or change the template id, then its not the recommended approach.

Better observe the event email_order_set_template_vars_before and in your observer method add or modify the order email template variables as per your requirement.

Sample code added below

app/code/Vendor/Module/etc/events.xml

<?xml version="1.0"?>
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:Event/etc/events.xsd">
    <event name="email_order_set_template_vars_before">
        <observer name="email_order_set_template_vars_observer" instance="Vendor\Module\Observer\OrderEmailSetTemplateVars" />
    </event>
</config>

Observer class - app/code/Vendor/Module/Observer/OrderEmailSetTemplateVars.php

<?php

namespace Vendor\Module\Observer;

use Magento\Framework\Event\ObserverInterface;
use Psr\Log\LoggerInterface;
use Magento\Framework\App\ObjectManager;
use Magento\Payment\Helper\Data as PaymentHelper;
use Magento\Sales\Model\Order;
use Magento\Sales\Model\Order\Email\Container\OrderIdentity;
use Magento\Sales\Model\Order\Email\Container\Template;
use Magento\Sales\Model\ResourceModel\Order as OrderResource;
use Magento\Sales\Model\Order\Address\Renderer;
use Magento\Framework\DataObject;

class OrderEmailSetTemplateVars extends \Magento\Sales\Model\Order\Email\Sender implements ObserverInterface 
{
    /**
     * @var LoggerInterface
     */
    protected $logger;
    
    /**
     * @var Template
     */
    protected $templateContainer;

    
    /**
     * @var PaymentHelper
     */
    protected $paymentHelper;

    /**
     * @var OrderResource
     */
    protected $orderResource;

    /**
     * Global configuration storage.
     *
     * @var \Magento\Framework\App\Config\ScopeConfigInterface
     */
    protected $globalConfig;

    /**
     * @var Renderer
     */
    protected $addressRenderer;

    /**
     * Application Event Dispatcher
     *
     * @var ManagerInterface
     */
    protected $eventManager;

    /**
     * @param Template $templateContainer
     * @param OrderIdentity $identityContainer
     * @param Order\Email\SenderBuilderFactory $senderBuilderFactory
     * @param \Psr\Log\LoggerInterface $logger
     * @param Renderer $addressRenderer
     * @param PaymentHelper $paymentHelper
     * @param OrderResource $orderResource
     * @param \Magento\Framework\App\Config\ScopeConfigInterface $globalConfig
     * @param ManagerInterface $eventManager
     */
    public function __construct(
        Template $templateContainer,
        OrderIdentity $identityContainer,
        \Magento\Sales\Model\Order\Email\SenderBuilderFactory $senderBuilderFactory,
        \Psr\Log\LoggerInterface $logger,
        Renderer $addressRenderer,
        PaymentHelper $paymentHelper,
        OrderResource $orderResource,
        \Magento\Framework\App\Config\ScopeConfigInterface $globalConfig
    ) {
        parent::__construct($templateContainer, $identityContainer, $senderBuilderFactory, $logger, $addressRenderer);
        $this->paymentHelper = $paymentHelper;
        $this->orderResource = $orderResource;
        $this->globalConfig = $globalConfig;
        $this->addressRenderer = $addressRenderer;
        $this->identityContainer = $identityContainer;
        $this->logger = $logger ?: ObjectManager::getInstance()->get(LoggerInterface::class);
        $this->templateContainer = $templateContainer;
    }
    

    public function execute(\Magento\Framework\Event\Observer $observer)
    {
        $this->logger->debug('Observer '.__CLASS__.' called.');
        $transportObject = $observer->getEvent()->getTransport();
        
//        $transportObject = $observer->getEvent()->getTransportObject();
        $order = $transportObject->getOrder(); 
        $this->logger->debug('Order Id: ' . $order->getId());
        
        // you can use get this var in your order email template
        $transportObject->setData('test_var','Test Value'); // or $transportObject->getTestVar('Test Value');
        
        // get order's shipping method and set the email template based on that
        $shippingMethod = $order->getShippingMethod();
        $this->logger->debug('Order Shipping Method  ' . $shippingMethod);
        
        if ($this->templateContainer) {
            
            $this->templateContainer->setTemplateOptions($this->getTemplateOptions());

            if ($order->getCustomerIsGuest()) {
                $templateId = $this->identityContainer->getGuestTemplateId();
                $customerName = $order->getBillingAddress()->getName();
            } else {
                $templateId = $this->identityContainer->getTemplateId();
                $customerName = $order->getCustomerName();
            }
            
            if ($shippingMethod == 'freeshipping_freeshipping') {
                $templateId = 10; // set your template id here based on the shipping method
            }
            
            $this->templateContainer->setTemplateId($templateId);
            
            $orderEmailTemplateId = $this->templateContainer->getTemplateId();
            
            $this->logger->debug('set order email template id based on shipping method : ' . $orderEmailTemplateId);
        }
        
        
    }
}

Answer 2

We can't rewrite the method of an abstract class, in this case, it is \Magento\Sales\Model\Order\Email\Sender

Instead of that, we need to find the actual class that is being used, likely it is Magento\Sales\Model\Order\Email\Sender\OrderSender