Constructor injection in Doctrine 2 entity

echo

Hello,
I was wondering how to properly use constructor injection in doctrine entities. Let's say I have entity Photo that has property $location. I want to implement method getURL(). For me to be able to do that, I need to pass a service UrlProvider into entity. Has anyone an elegant solution.

Solution 1:
Use different model. Something like $urlProvider->getURL($photo) thus no method getURL() in photo entity.

Solution 2:
Use $container->callMethod(…) hooked as event postLoad().

Solution 3 (elegant):
?

Thanks for reviewing.

mkoubik

$photo->getUrl($urlProvider); seems good to me.

echo

mkoubik wrote:

$photo->getUrl($urlProvider); seems good to me.

Thank you for input. I'll extend my reasoning. If I iterate in template over entity collection it would be required to pass $urlProvider into template. This seems like over-kill to me.

mkoubik

Entity itself doesn't depend on $urlProvider, it uses it only in one method for external formating. Thus the only reasonable approches for me are

$entity->formatSomeProperty($helper);

and

$service->formatSomeProperty($entity);

both of them are unusable in templates. Personally, I would remap the entities to some single-purpose data bags, but I don't dare to seriously recommend this pattern to anybody yet.
Maybe someone who considers leaking persistence-layer objects into templates ok will help you with this :-)

Edit: maybe you could create template helper for this: {$photo->location|location2url}.

Last edited by mkoubik (2014-01-30 15:32)

Filip Procházka

I don't understand where is the problem

{foreach $photos as $photo}
	<a n:href="Photo:detail, $photo->id"><img n:src="$photo">

Method getUrl() should not be on the photo entity. You could have some “seoName” propety or “filename” property that contains relative path to storage and everything else should be solved in storage.

Have a look at https://github.com/brabijan/images

And lastly constructor injection with entities doesn't make sense. Entity lifecycle is that you create it, it get's persisted and whenever you load it from databaze it's unserialized, therefore you cannot use constructor for anything else than parameters and relations of the entity. The only thing you can use is method injection using entity listeners. But I would strongly advise not to do that (at least not at this case), because you're trying to hack it with wrong design. Use proper storage.

Last edited by Filip Procházka (2014-01-30 17:08)