1. DI (Dependency Injection) / IOC (Inversion Of Control)
PHP+SQL 7.
DI (Dependency Injection) / IOC (Inversion Of Control)
OE NIK, 2013

2. It is hard to write a good code!
Keywords: decoupling, loose coupling!
Ránézésre olvasható nevekkel: + ránézésre olvasható teszt is legyen
Az egymástól való függetlenítés miatt akár kódduplikáció is simán megengedett

3. This also helps us in writing good tests!
The tests must be fast
Slow tests are impossible to run over and over again  test will not be executed, bugs will be found later
The tests must be independent
Order, timing, etc. must not affect the results
Naming convention must be easy-to-read
A good test list is basically a requirement-list
We must not cover every possible inputs
Examples are good, finding the corner cases are important!
Only test a single feature of a single class
Always independent from the live data (database/settings)
We can substitute the dependencies too: Dependency Injection + fake dependencies, mocking...
Ránézésre olvasható nevekkel: + ránézésre olvasható teszt is legyen
Az egymástól való függetlenítés miatt akár kódduplikáció is simán megengedett

4. Dependency Injection
We provide the dependencies of the classes externally – via interfaces, which allows us
To exchange the dependency later at any time to another class – while keeping the interface
To perform “truly” independent individual unit-tests
When developing, we can use any instance of the interface
The instance can be automatically created: DI container
Dependencies of the dependencies: IoC container
When testing, we replace the dependency with a known and simple object solely created for the tests
The class will be independent from the dependency
Various ways: fakes, mocks, dummies, stubs …

5. Constructor Injection
interface IMyDependency {
string DoSomething(); }
class MyClass
private IMyDependency dependency;
public MyClass(IMyDependency dependency)
this.dependency = dependency;
// in methods: dependency.DoSomething()
// usage
IMyDependency myDependency; // + instance creation somehow...
MyClass myClass = new MyClass(myDependency);
OE-NIK HP

6. Dependency Injection
OE NIK, 2013

7. IoC/Service container
OE NIK, 2013

8. In symfony In a controller, $this->container is an IoC container
// controller shortcut $service = $this->get('xxx');
// real call $service = $this->container->get('xxx'); $service = $instanceOfContainerInterface->get('xxx');
Services can be defined in services.yml to be used later
services: app.carfactory: class: AppBundle\Service\CarServiceFactory arguments: app.carservice: class: AppBundle\Service\ICarService factory: getService]
OE NIK, 2013

9. In symfony Download & uncompress php_code_06_ormEntities.zip
php bin/console debug:container app (also: debug:route, debug:twig)
TO READ:
dependency-injection-vs-service-locator-best-practice
dependency-injection-with-symfony-2
OE NIK, 2013

10. OE NIK, 2013

11. OE NIK, 2013