[Workflow] Document the fact workflows are tagged

[javiereguiluz]

Fixes #20876.

This makes the same changes we did in #21382 when explaining the #[Target] attribute and then it addresses the issue explained in #20876.

[javiereguiluz]

Pinging @lyrixx in case he has some time to review this change. Thanks!

[lyrixx]

Thanks for taking care of this PR.

[lyrixx]

IMHO the target is much much better. What about putting this one before the "Use a specific argument name" ?

[lyrixx]

🤔 This does not work, does't it?

According to the PHPDoc :

1. A tag name or an explicit list of service ids
2. The name of the attribute that defines the key referencing each service in the locator

---

You can use the full service name: <workflow_type>.<worflow_name>. Example state_machine.blog_publishing (Note: I did not check if it's a state machine or a workflow, in your example)

But this this is kinda useless IMHO.

---

The whole point it to inject them all, and get lazy loading:

    public function __construct(
        #[AutowireLocator('workflow')] // <-- this is not the workflow name, but the tag name
        private ServiceLocator $workflows,
    ) {
    }

    #[Route(path: '/foobar')]
    public function foobar()
    {
        dd($this->workflows->get('workflow.article')); // <-- this is the service ID. See above
    }

But, IMHO, this is a bit boring to prefix by workflow. or state_machine.

That's why I prefer:

    public function __construct(
        //                      This is the tag name
        //                     /          This is index attribute, see https://github.com/symfony/symfony/blob/74fc896a8e13930a27037f7c97c76ca353ae1a51/src/Symfony/Bundle/FrameworkBundle/DependencyInjection/FrameworkExtension.php#L1201-L1202
        //                   /           /
        #[AutowireLocator('workflow', 'name')]
        private ServiceLocator $workflows,
    ) {
    }

    #[Route(path: '/foobar')]
    public function foobar()
    {
        dd($this->workflows->get('article')); // Now this is the workflow name (without any prefix)
        dd($this->workflows->get('task')); // Same same
    }

And, if you wan to get only workflow, or only state machines:

public function __construct(
        #[AutowireLocator('workflow.workflow', 'name')]
        private ServiceLocator $workflows,
        #[AutowireLocator('workflow.state_machine', 'name')]
        private ServiceLocator $stateMachines,
    ) {
    }

    #[Route(path: '/foobar')]
    public function foobar()
    {
        dd($this->workflows, $this->stateMachines);
    }

---

All my examples work, and have been tested with https://github.com/lyrixx/SFLive-Paris2016-Workflow ; I also tested all feature, and they are available in 6.4 too

EDITS

1. I'm not sure it actually works. I'm investigating !
2. it do works on 6.4, but not on 7.4. So there is a bug somewhere. Will fix it!
3. okay, no bugs. I need ALL the app to be in 7.4 (even the DIC to get symfony/symfony@8b79ff5)

[javiereguiluz]

Grég, thanks for such a fantastic review 🙇

I made all the changes and fixes that you pointed out. Thanks!

[lyrixx]

Nice 👍🏼

I still prefer the "target" option over the "specific argument name", but it's good to me

[javiereguiluz]

Yes, #[Target] is better, but I preferred to keep consistency with the other examples of the docs.

Let's do something. Let's change this in 8.0 branch after the Symfony 8.0 release and let's show only the #[Target] config while adding the other way in a small note for each example.

[lyrixx]

👍🏼

Thanks for taking care of this PR!