Inyección de dependencia

Hey @Akili!

Very interesting questions! Let me do my best to answer :)

About your Dependency Injection Container with Autowiring and I believe Reflections

Yup, reflection is definitely used internally to determine the type-hint of an autowireable argument.

Does Symfony use PHP-DI, Symfony-DI or both with similar features

Symfony has its own symfony/dependency-injection component that holds all of this logic - it doesn't use PHP-DI.

I was also curious about how you were able to get the terminal to display data about the Service Container and Parameter Container

This is one of the super-powers of Symfony's dependency injection system. It builds up ALL of the metadata of what every service is and every argument to every service. And so, dumping a list of this then becomes quite easy. Internally, this metadata is known as the ContainerBuilder. The ContainerBuilder is aware of EVERY service and EVERY argument.

Would it be too much of an ask, by asking, if you would be able to provide a great source of learning material regarding Dependency Injection Container

We have a very old tutorial - based on Symfony 3 - that talks a lot about this - https://symfonycasts.com/screencast/symfony-journey-di - the code will be out of date, and it doesn't show how autowiring works (iirc, it was built before autowiring exists in Symfony) but it will show the fundamentals of the dependency injection system and how the container is built.

wish you guys had a location based in california that would allow me to volunteer my services...

A fellow USA person! I'm based on Michigan :)

Cheers!

Thanks Ryan!

I really appreciate you for this.

Hey t5810,

The correct answer is A because the CacheInterface $cache is just an argument of the method, which technically is a dependency of the class, but it's not a property, so only that method depends on it but not the whole class. You may ask, but we do the same to Symfony controllers, yes, but they're a special kind of service, the Symfony container takes care of "injecting" all of the controller's method arguments

I hope this makes sense to you :) Cheers!

Hi MolloKhan
I re-watched the video again, I re-read the question 3 times and THEN I noticed the bold and capital NOT in the question....
Sorry for wasting your time...

Regards

haha, it happens! You're welcome :)

Hey @Alin-D

The $cacheItem object it's not a dependency of the MixRepository class. It's an argument you get passed by the callback function of the $this->cache->get() method call. In other words, the second argument of that method is a callback function, and it will pass to you an instance of CacheItemInterface. I hope it's more clear now

Cheers!

Hey Stefaaan,

I think this tutorial should answer this question :) In short, if you need some job to do, and you would like to be able to re-use it in a few places or test it - there is a good plan to create a service for this.

Cheers!

Howdy Alexander!

I edited your post just to make it a tad bit easier to read the classes and what they are doing. Anywho, I spent a few minutes playing around with this use case and I think I see what the problem is.

Symfony is great managing parent services when they only extended one level. E.g. Class One extends Abstract Class Two. But when we throw in a second abstraction level into the mix, we start hitting limitations with Symfony's auto-wiring and PHP's inheritance.

Because AbstractClassTwo extends AbstractClassThree and both of them have constructors(), I believe you will need to pass in the arguments for Three into Two's constructor like so:

abstract class Two extends Three
{
    public array $arr;

    public function __construct(string $injectedVar, array $arr = [])
    {
        parent::__construct($injectedVar);

        $this->arr = $arr;
    }
}

Otherwise Three's constructor is never called. Even when I tried your example using the "Common Dependency Method" shown in the docs: https://symfony.com/doc/current/service_container/parent_services.html - I had the same issue.

I Hope this helps!

Thanks for the response and the time to dig in to find a solution. I also noticed in the docs (just above this line: https://symfony.com/doc/current/service_container/injection_types.html#immutable-setter-injection):

These advantages do mean that constructor injection is not suitable for working with optional dependencies. It is also more difficult to use in combination with class hierarchies: if a class uses constructor injection then extending it and overriding the constructor becomes problematic.
Emphasis mine.

I had also gotten your solution to work, it just seemed a little ugly compared with the way dependency injection usually seems to work.

Hey Kaan,

Is it a question? :) Like do you want to know if SymfonyCasts tutorials will help you to understand Symfony framework better after a year of its learning on our platform? Or are you just leaving feedback about SymfonyCasts?

Cheers!

it was actually a compliment sir..
i watched plenty of videos like 'symfony for beginners' or 'creating a blog system with symfony' but none of them explain what Symfony is. before watch your videos i was know to how to code with Symfony but i had no idea about how that machine works : )

thank you for your effort and forgive my terrible English..
i hope to made myself clear : )

Hey Kaan,

Ah, I see! The question marks in your first message confused me a bit :)

Thank you for your kind words about SymfonyCasts - that's exactly what our mission is, we're trying to explain complex things in a simple and understandable way for everyone, even newcomers :) So, we're really happy to hear our service is useful for you ;)

Cheers!

Hey Lubna,

If you have a static value for the global variable or when you need to make some env var global in twig - you can use this way: https://symfony.com/doc/current/templating/global_variables.html

But if you need a data from your repository - probably that global Twig var won't help you. In this case, you can create a custom Twig function that will return whatever you want, we're talking about custom Twig functions here: https://symfonycasts.com/screencast/symfony4-doctrine/twig-extension

Or you can check the Symfony's Twig docs about it.

Cheers!

Hi! Thanks for understanding my problem correctly.
Gonna try your suggestion!

Best,
Lubna

Hey Lubna,

You're welcome! Good luck with it ;)

Cheers!