DX: Creating lazy services is too difficult/obscure/bespoke/brittle

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IIRC this was critical for certain aspects of the Drupal bootstrap process to become sufficiently fast in the majority of cases.

So the work that gets done here almost certainly will need to provide profiling data if it changes lazy services, and certainly if it removes them altogether.

That being said: +1 to this being poor DX right now. It's painful to make service lazy.

Symfony 6.2 supports lazy services out of the box: https://symfony.com/doc/current/service_container/lazy_services.html

We should figure out how this works and see if we can swap our custom implementation to using Symfony's.

I think that was already attempted in 📌 Deprecate Drupal ProxyBuilder in favor of Symfony lazy services Closed: won't fix .

You want ServiceClosureArgument

Your problem is our YAML loader AFAIK doesn't support it

You want to add a notation like the already existing @? probably @> because it's reminiscent of fn () => and probably upstream it too -- Symfony has its own way to do it using some godforsaken YAML notation uglier than sin and waaaaay too long, too.

Re: ##13, we're using this pattern at 🐛 Cache bin names should be set from service tags, not the service name Needs work though as mentioned, the Drupal container doesn't support it directly. I disagree that the Symfony syntax is too ugly to use, but service closure is a good candidate here to remove all this even uglier boilerplate.

📌 Add support for !service_closure custom tag in YamlFileLoader Fixed ?

Does this mean we could deprecate the existing lazy proxy creation script and require any new core lazy services be injected with a service closure or something else less boilerplate?

Yeah, arguments: [!service_closure '@example_service_1'] is exactly the godforsaken ugly syntax I mentioned. Nah. We could and should do better: arguments: ['@>example_service_1'] and be done.

We already support the nice thing, \Symfony\Component\DependencyInjection\Attribute\AutowireServiceClosure. AFAICT.

Symfony Docs

!service_closure should be avoided in new code.

Does this mean we could deprecate the existing lazy proxy creation script

A worthwhile cause <3

Note 📌 Add support for !service_closure custom tag in YamlFileLoader Fixed went in recently.

I created 📌 Replace lazy service proxy generation with service closures Active to look at the service closure approach. It might be a big change to do in one go, so we could split it into smaller tasks.

Note #17 has been fixed in https://github.com/symfony/symfony/commit/ba299601bf460a5888a511d2c6da16... do we want to patch your yaml loader?

#23 oh that's a nice little improvement, yes we should add that to Drupal too!

Created an issue for #23 📌 Support service closure shorthand syntax in YamlFileLoader Postponed