Symfony Tutorial Container Service 2 - Dependency Injection

In the next part of the Symfony services tutorial series we are going to look at how we can use Symfony services to make our application more extensible. We are going to create a set of user validation routines that adhere to a PHP interface. This decouple the validator logic from the Symfony controller and our validation routine.
We will be using dependency injection to pass other services into each other

We cover a lot in this tutorial including:
- PHP Interfaces
- Symfony controllers
- Symfony dependency injection
- Using the Symfony service container
- A discussion on good coding practices

Code can be found on github:

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[abdelhadihabchi]

Thank you much Peter you saved my life :'(, I learnt a lot of things from you again

[JesusValeraReales]

For all those who don't work and are using Symfony 3.4. You should replace from 'services.yml' the 'app.validation_user' by the following line:
or even

In that version, you MUST set in the interface which implementation you are looking for, NOT to set into the validation which class you want to use.

Cheers and happy coding!

[midimojo]

Stick to PSR-2 (opening braces MUST go on a new line). Especially in a tutorial, there's too much bad/ugly PHP out there already. Other than that it's a good tutorial to explain the basics of DI. I was searching for more info about the container as I get a bit confused with it while unit testing as there are times you don't want to mock and stuff.