IoC container beyond constructor injection

Did you know your IoC container can do a whole lot more than just constructor injection? Besides that it is actually packed with features. Inflectors, resolving callbacks, aliasing, method invocation to name a few. In this talk you will learn how to leverage the power of a great container and service providers to write better, loosely coupled code. Well designed code put together by your IoC container will make your applications SOLID, modular, lean and decoupled from the framework!

Feedback here: http://www.meetup.com/Laravel-Cologne/events/231240611/

Transcript

1. IOC container beyond constructor injection @hannesvdvreken #laravelcologne
2. Hi, my name is Hannes.
3. !
4. madewithlove.be
6. IoC Container
7. CONSTRUCTOR INJECTION illuminate/container league/container symfony/dependency-injection aura/di … container-interop/container-interop
8. Automatic constructor injection
9. class SendInvoice { public function __construct(Mailer $mailer) { $this->mailer = $mailer; } public function listen(InvoiceGeneratedEvent $event) { … } }
10. CONSTRUCTOR INJECTION Constructor injection
11. $app->make(SendInvoice::class);
12. CONSTRUCTOR INJECTION Reflection
13. (new \ReflectionClass($class)) ->getConstructor() ->getParameters();
14. CONSTRUCTOR INJECTION Recursively
15. Helping the container
16. REGISTRATION Service Providers
17. class ServiceProvider { public function register() { … } }
18. class ServiceProvider { public function boot(Mailer $mailer) { … } }
19. class ServiceProvider { public function provides() { return […]; } }
20. REGISTRATION Register bindings in the register method
21. REGISTRATION - BINDING $this->app->bind( MailerContract::class, ConcreteMailer::class );
22. REGISTRATION - BINDING $this->app->bind(Mailer::class, function ( … });
23. REGISTRATION - BINDING $this->app->singleton(Mailer::class, funct … });
24. REGISTRATION - BINDING $this->app->alias( Mailer::class, 'mailer' );
25. REGISTRATION Bind everything with its class name
26. REGISTRATION Bind everything with its interface
27. REGISTRATION Unless you bind multiple versions
28. REGISTRATION $this->app->bind('fs.photos', function () $this->app->bind('fs.files', function () {
29. REGISTRATION - CONTEXTUAL BINDING Contextual binding
30. REGISTRATION - CONTEXTUAL BINDING $this->app ->when(PhotosController::class) ->needs(FilesystemInterface::class) ->give('fs.photos');
31. REGISTRATION - CONTEXTUAL BINDING No more DB::connection('db1')->table($table)->…;
32. $this->app->bind('db.1', function () { return $this->app['db'] ->connection('db1'); }); $this->app ->when(EventListener::class) ->needs(ConnectionInterface::class) ->give('db.1');
33. Inflection REGISTRATION - CONTAINER EVENTS
34. REGISTRATION - CONTAINER EVENTS Inflection (aka “container events”)
35. REGISTRATION - CONTAINER EVENTS $this->app->resolving(function () {});
36. use App\Contracts\EnvironmentAware; $this->app->resolving( function (EnvironmentAware $object) { $object->setEnv( $this->app->environment() ); } );
37. interface EnvironmentAware { public function setEnv($env); }
38. trait EnvironmentAware { public function setEnv($env) { $this->env = $env; } private function isEnv($envs) { return in_array($this->env, (array) $envs); } }
39. REGISTRATION - CONTAINER EVENTS Method injection
40. $this->app->resolving(function (Mailer $ma { $mailer->setQueueResolver(function () { );
41. $this->app->resolving(function (Validator) { $fileTypes = $app['config']->get(…) $validator->setAllowedFileTypes($fileT );
42. $this->app->resolving(function (Mailer $ma { $mailer->setQueueResolver(function () … }); );
43. REGISTRATION - TAGGING Tagging
44. $this->app->tag('fs.files', 'fs'); $this->app->tag('fs.photos', 'fs');
45. $this->app->tagged('fs');
46. Using the container
47. CALLING THE CONTAINER Preferably only for - Factories - Event Listeners - Controllers - Command Handlers
48. $this->app->make('fs'); $this->app->make('fs', […]); $this->app->bind( 'fs', function ($app, $args) {…} );
49. $this->app->call(function (Mailer $mailer) $this->app->call([$listener, 'handle']); $this->app->call('Listener::handle'); $this->app->call('Listener@handle');
50. $func = $this->app->wrap('Listener@handle' $func();
51. $this->app->tagged('fs');
52. Bonus
53. BONUS - SOFT DEPENDENCIES Solving soft dependencies
54. BONUS - SOFT DEPENDENCIES $func = function () { return $this->app->make('queue'); } $mailer->setQueueResolver($func);
56. BONUS - CIRCULAR DEPENDENCIES Solving circular dependencies
57. BONUS - CIRCULAR DEPENDENCIES $mailer = new Mailer(QueueInterface $queue); $queue = new Queue(MailerInterface $mailer);
58. BONUS - CIRCULAR DEPENDENCIES $mailer = new Mailer(); $queue = new Queue(MailerInterface $mailer); $mailer->setQueueResolver(function () use ($qu return $queue; });
59. BONUS - NOT SUPPORTED Not supported!
60. BONUS - NOT SUPPORTED Contextual binding for methods
61. BONUS - NOT SUPPORTED https:/ /github.com/laravel/ framework/pull/12183
62. BONUS - CIRCULAR DEPENDENCIES $this->app—>when('Foo@bar') ->needs(QueueContract::class) ->give('queue.redis');
63. Reflection Binding Calling code Bonus
64. Thank you! https://joind.in/talk/xxxxx @hannesvdvreken #laravelcologne
65. Time for questions. @hannesvdvreken #laravelcologne
66. • http:/ /mwl.be REFERENCES