Attach entity history/changes to the entity as OneToMany association - php

Question

I've an entity Order, with a property events which should contain a list of all changes made to this entity.
The Order class:
<?php
/**
* #ORM\Entity
*/
class Order
{
// more stuff...
/**
* #ORM\OneToMany(
* targetEntity="OrderEvent",
* mappedBy="order",
* cascade={"persist", "merge"}
* )
*/
protected $events;
// more stuff...
}
The OrderEvent class:
/**
* #ORM\Entity
*/
class OrderEvent
{
// more stuff...
/**
* #ORM\ManyToOne(targetEntity="Order", inversedBy="events")
* #ORM\JoinColumn(nullable=false)
*/
protected $order;
// more stuff...
}
class OrderLifecycle
{
public function preUpdate(Order $order, PreUpdateEventArgs $args)
{
$changes = $args->getEntityChangeSet();
if (!empty($changes)) {
$event = new OrderEvent();
$event->setOrder($order)
->setChanges($changes);
$order->addEvent($event);
return $event;
}
}
}
But according to the doctrine documentation, the preUpdate method should not be used to change associations.
What is the recommended way to do things like this one?
I am using Zend Framework 2, but I think that's not relevant.

Answer 1

I think in this case you could use PostUpdate event. In that case you are sure that the update action was successful and you can do what you want; add the new OrderEvent instance to your $events collection.
EDIT
You are not the first one implementing such thing. Maybe you should check existing examples and see how they deal with this (or even consider using it). For example the Gedmo Loggable solution.
With this extension you can mark entities as loggable with a simple #annotiation:
/**
* #Entity
* #Gedmo\Loggable
*/
class Order
{
// Your class definition
}