Domain-Driven Design in PHP

Instantiating Application Services

Instantiating just your Application Service is easy, but building the dependency tree might be tricky, depending on how complicated the dependencies are to build. For such a purpose, most frameworks come with a Dependency Injection Container. Without one, you'll end up with something like the following code somewhere in your controller:

$redisClient = new Predis\Client([    'scheme' => 'tcp',    'host' => '10.0.0.1',    'port' => 6379]);$userRepository = new RedisUserRepository($redisClient);$signUp = new SignUpUserService($userRepository);$signUp->execute(new SignUpUserRequest(    '[e-mail]',    'password'));

We decided to use the Redis implementation for the UserRepository. In the previous code example, we ...