Events

Thelia dispatch a lot of events during various workflows : account creation, order process, ...
You can listen any of this event to add or replace logic. Or add your own events that can be listened by other modules.
More info for Event dispatcher component can be found on Symfony documentation

To do this you have to create an event subscriber, it's just a simple class that implement the EventSubscriberInterface with a getSubscribedEvents function to choose what event to listen :

<?php

namespace MyModule\EventListener;

use Symfony\Component\EventDispatcher\EventSubscriberInterface;
use Symfony\Component\HttpFoundation\RequestStack;
use Thelia\Core\Event\TheliaEvents;

class LogoutListener implements EventSubscriberInterface
{
    protected $requestStack;

    public function __construct(RequestStack $requestStack)
    {
        $this->requestStack = $requestStack;
    }


    public static function getSubscribedEvents($event)
    {
        // return the subscribed events, their methods and priorities
        return [
            TheliaEvents::CUSTOMER_LOGOUT => ['onCustomerLogout', 30]
        ];
    }

    public function onCustomerLogout()
    {
       // Do what you want at customer logout
    }
}

Native events

Thelia native events are all listed in TheliaEvents class

Propel events

Propel dispatch several events during model lifecycle :

Constant name	Description
PRE_SAVE	Before persisting the object
POST_SAVE	After persisting the object
PRE_INSERT	Before inserting to database
POST_INSERT	After inserting to database
PRE_UPDATE	Before updating the object in database
POST_UPDATE	After updating the object in database
PRE_DELETE	Before deleting the object in database
POST_DELETE	After deleting the object in database

Those constants are accessible to the class of model name suffixed by Event.
For example to listen product update use this event ProductEvent::POST_UPDATE

<?php

namespace MyModule\EventListener;

use Symfony\Component\EventDispatcher\EventSubscriberInterface;
use Symfony\Component\HttpFoundation\RequestStack;
use Thelia\Model\Event\ProductEvent;

class ProductListener implements EventSubscriberInterface
{
    public static function getSubscribedEvents($event)
    {
        // return the subscribed events, their methods and priorities
        return [
            ProductEvent::POST_UPDATE => ['postProductUpdate', 30]
        ];
    }

    public function postProductUpdate(ProductEvent $event)
    {
        $productModel = $event->getModel();
       // Do what you want with the product
    }
}