initial design of using attributes for injection

[frederikbosch]

use Aura\Di\Attribute\Instance;
use Aura\Di\Attribute\Service;
use Aura\Di\Attribute\Value;

class FakeConstructAttributeClass
{
    private FakeInterface $fakeSetter;

    public function __construct(
        #[Service('fake.service')]
        private FakeInterface $fakeService,
        #[Service('fake.service', 'getFoo')]
        private FakeInterface $fakeServiceGet,
        #[Instance(FakeInterfaceClass1::class)]
        private FakeInterface $fakeInstance,
        #[Value('fake.value')]
        private string $string,
    ) {
    }

    public function setFake(
        #[Service('fake.setter')]
        FakeInterface $fakeSetter
    ) {
        $this->fakeSetter = $fakeSetter;
    }
}

Design choices:

• All attributes define lazy injections
• Attributes will have the lowest precedence, e.g. ->params[FakeConstructAttributeClass::class]['fakeService'] = ... will overwrite the attribute.

Limitations:

• You cannot pass params to #[Instance] attributes. If you want to overwrite constructor parameters of an injected instance, you would have to change to an #[Service] attribute or reside to inject by code.

  $container->params[FakeConstructAttributeClass::class]['fakeService'] = $container->lazyNew(MyClass, [
  'param1' => $container->lazyGet('service')
  ]);

• You cannot pass params to #[Service('service', 'method')] attributes. You would have to reside to the method using code, or define an additional service and then use #[Service('new.service)].

  $container->set('new.service', $container->lazyGetCall('service', 'method', $container->lazyNew(OtherClass::class))

I will continue with the implementation if there is no objection towards this direction. I will take at least a week before continuing.