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Dependency injection in ZF2 and Symfony 2 are service locators
Apr 16, 2013 @ 12:40:07

On Reddit's PHP section there's a discussion happening about dependency injection versus service locators in two popular PHP frameworks - Zend Framework 2 and Symfony 2 (and how they're not really DI at all).

Both ZF2 and Symfony 2 offer the same behavior: if I'm in a controller, and I want to use a service, I have to get it from the container with $this->get('my_service'). As such, the controller is not using DI, this is the service locator pattern. Controllers become more difficult to tests because of that, and they depend on the container now. I wonder why both frameworks didn't go further: why not treat controllers like services and use dependency injection on them. In other words: if a controller needs a service "A", then it should get it in the constructor, or through setter/property injection.

The comments talk some about the "controller from the DI container" idea, some other ways around the problem and some clarification as to what the frameworks are actually doing related to the container injection.

tagged: dependency injection service locator controller framework zendframework2 symfony2

Link: http://www.reddit.com/r/PHP/comments/1caidn/dependency_injection_in_zf2_and_symfony_2_are