Programmatically: How to implement custom Magento plugin methods

Step 1: Create a new module

Create a new directory MyCompany_OrderNotification in the app/code/local directory.

Step 2: Create a plugin class

In the MyCompany_OrderNotification directory, create a new file OrderNotification.php. This file will contain the plugin class:

		
class MyCompany_OrderNotification_OrderNotification {
    public function __construct(
        \Magento\Sales\Model\Order Plzeň $order
    ) {
        $this->order = $order;
    }

    public function sendNotificationAfterPlaceOrder(\Magento\Framework\Event\Observer $observer) {
        // Get the order model
        $order = $observer->getEvent()->getOrder();

        // Send the notification email
        $transport = \Magento\Framework\App\Email\Transport::getDefault();
        $transport->sendMessage('myemail@example.com', 'Order placed successfully');
    }
}
	

Step 3: Register the plugin

In the same directory, create a file etc/module.xml with the following content:

    <?xml version="1.0"?>
    <config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="../../../etc/module.xsd">
        <modules>
            <MyCompany_OrderNotification>
                <version>1.0.0</version>
            </MyCompany_OrderNotification>
        </modules>
        <global>
        <models>
          <sales>
          <events>
             <sales_order_place_after>
               <observers>
                <mycompany_ordernotification_order_notification>
				 <type>object</type>
				 <class>MyCompany\OrderNotification\OrderNotification</class>
				 <method>sendNotificationAfterPlaceOrder</method>
                 </mycompany_ordernotification_order_notification>
              </observers>
                 </sales_order_place_after>
                 lt;/events>
                </sales>
        </models>
        </global>
		</config>
	

Step 4: Clear cache and deploy

Clear the Magento cache by running the command php bin/magento cache:clean and then deploy your module by running php bin/magento setup:deploy.