Trigger event after an order has been created/saved

Question

We are currently having a issue with the Observer, most likely we did something wrong, but I have no clue what I've did wrong.

Basically, we created a module with an observer:

namespace Vendor\Customer\Observer;
use Magento\Framework\Event\ObserverInterface;
use Magento\Framework\Event\Observer;
use Vendor\Customer\Model\Customer;
use Vendor;

class SalesOrderSaveAfter implements ObserverInterface {
    /** @var \Magento\Framework\Logger\Monolog */

    protected $logger;
    protected $_customer;

    public function __construct(\Psr\Log\LoggerInterface $loggerInterface, 
            \Vendor\Customer\Model\Customer $customer) {
        $this->logger = $loggerInterface;
        $this->_customer = $customer;
    }

    /**
     * fires when sales_order_save_after is dispatched
     * 
     * @param Observer $observer
     */
    public function execute(Observer $observer) {
        $order = $observer->getEvent()->getOrder();
        $result = (array) $this->_customer->getOrderData($order);
    }
}

The problem is, that the module fires the action when the customer clicks on "Place order" in the frontend.

When the customer clicks on "Place order" he will be redirected to a third party payment provider, and after the customer is finishing his payment there, he comes back to the Success-Page, where this Observer triggeres AGAIN.

The result of this is that the observer is triggered twice in one payment process. This seems buggy.

So the question is: how can I tell the Observer to only fire once and only if the payment is successfully done (= when reaching the Success-Page)?

Answer 1

you can use the event checkout_onepage_controller_success_action at Namespace\module\etc\frontend\events.xml :

<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:Event/etc/events.xsd">
<event name="checkout_onepage_controller_success_action">
    <observer name="mymodule_controller_success_action" instance="Namespace\Module\Observer\MyObserver"  />
</event>

Answer 2

Observe the sales_order_place_after event instead.

Answer 3

The main problem with checkout_onepage_controller_success_action is that you do not necessarly go this page. For instance if you make a payment via credit card, it is not compulsory to go back to the merchant website.

Answer 4

You need to create observer for checkout_submit_all_after event. In this way you will have access to the saved order and quote data in your observer. If something happens in your extension that won't prevent order from being saved. Plus you observer will be called once.