Improved the advantages/drawbacks of "controllers as services"

[javiereguiluz]

This fixes #6749.

[Jean85]

LGTM 👍
Status: reviewed

[HeahDude]

I think it is worth clarifying the semantic above, because technically this is not the constructor of a controller but of a class of controllers, in this way a Dunglas action is more a controller than the base controller class.

[HeahDude]

I don't really agree, controller's method should be as thin as possible and just calling services to do things to end by returning a response (so I've been told :). If services are there no need for shortcuts anymore. In the end you're just calling explicitly some methods, some would say "without magic" :D.

Again the semantic does not look appropriate because from a DI point of view defining an object makes it a service, but orchestrate an action requires to call every needed services, hence the need to access them.

The way we always used in Symfony is by making the controller class container aware, but defining explicitly the needed dependencies is not that different since the controller class is just virtual, what's truly needed is a locator and to group actions by scopes.

The new locator feature is awesome for this, and Symfony is great for letting every ways of coding possible, because they are all powerful in their way, one just need to do and learn what he can and want to do with it.

Personally I don't prefer one way or another, as long that it makes sense to do what you got to do.

By letting everyone playing with it some ways may die naturally on the long run.

[javiereguiluz]

I'm sorry but I don't understand your comment. Let me show you why I wrote that phrase.

---

For such a common thing as rendering a template, if you use the base controller, you do this:

return $this->render('homepage.html.twig');

Just 1 short and beautiful PHP line.

However, if you don't use that base controller, the equivalent code is this one:

        if (!$this->container->has('twig')) {
            throw new \LogicException('...');
        }
        
        $response = new Response();
        $response->setContent($this->container->get('twig')->render('homepage.html.twig'));

        return $response;

---

So, I think the previous phrase is correct: "It takes more work" ... and "they become more verbose".

[HeahDude]

But if the Twig environment is a hard (or safe) dependency, it could just be:

return $this->twig->renderResponse('homepage.html.twig');

[javiereguiluz]

Well, the working example would be:

private $twig;

public function __construct(\Twig_Environment $twig)
{
    $this->twig = $twig;
}

return $this->twig->renderResponse('homepage.html.twig');

So, again, "it takes more work" and "they become more verbose" 😄

[HeahDude]

The class is but not the controllers in it :p

[wouterj]

👍

[xabbuh]

Thank you Javier.