How I learned to Stop Wiring and Love Autowiring Containers

Does managing YAML, XML or PHP container configurations make you sad? Do you dread making changes to your classes' dependencies for fear of the inevitable container configuration wiring blues? Life doesn't have to be this way! Not if your container supports autowiring, that is. Hear one developer's journey into the wild world of containers, learn how autowiring works, and find out how using autowiring can free you from having to manually configure every dependency.

Transcript

1. How I learned to Stop Wiring and
   Love Autowiring Containers
   Beau Simensen • beausimensen.com • @beausimensen
   

   View Slide

2. Terminology
   

   View Slide

3. History
   

   View Slide

4. Implementations
   

   View Slide

5. View Slide

6. SOLID
   

   View Slide

7. D
   Dependency Injection?
   

   View Slide

8. D
   Dependency Inversion
   

   View Slide

9. Inversion of Control
   

   View Slide

10. Dependency Injection
    

    View Slide

11. Service Locator
    

    View Slide

12. Dependency Inversion .-- Dependency Injection
    |
    Inversion of Control --+
    |
    `-- Service Locator
    

    View Slide

13. Dependency Inversion .-- Dependency Injection --.
    | |
    Inversion of Control --+--------------------------+-- Container
    | |
    `-- Service Locator -------'
    Dependency Injection Container
    Inversion of Control Container
    Service Container
    

    View Slide

14. Dependency Inversion .-- Dependency Injection --.
    | |
    Inversion of Control --+--------------------------+-- Container
    | |
    `-- Service Locator -------'
    Dependency Injection Container
    Inversion of Control Container
    Service Container
    Container
    

    View Slide

15. Dependency Inversion .-- Dependency Injection --.
    | |
    Inversion of Control --+--------------------------+-- Container
    | |
    `-- Service Locator -------'
    Dependency Injection Container ## .
    Inversion of Control Container ## ## ## ==
    Service Container ## ## ## ## ===
    Container /""""""""""""""""\___/ ===
    ~~~ {~~ ~~~~ ~~~ ~~~~ ~~ ~ / ===- ~~~
    \______ o __/
    (no, not that other type of container) \ \ __/
    \____\______/
    

    View Slide

16. Wiring
    

    View Slide

17. services:
    app.word_list:
    class: 'AppBundle\Game\WordList'
    calls:
    - [ 'addWord', [ 'computer' ] ]
    - [ 'addWord', [ 'monitors' ] ]
    - [ 'addWord', [ 'cellular' ] ]
    public: false
    app.game_context:
    class: 'AppBundle\Game\GameContext'
    arguments: ['@session']
    public: false
    app.game_runner:
    class: 'AppBundle\Game\GameRunner'
    arguments: ['@app.game_context', '@?app.word_list']
    

    View Slide

18. View Slide

19. Spring Framework's
    IoC Container
    

    View Slide

20. Beans
    

    View Slide

21. Explicit Wiring
    

    View Slide

22. XML > Annotations
    

    View Slide

23. 
    
    class="org.springbyexample.di.app.Message">
    
    
    
    

    View Slide

24. Google's Guice
    a lightweight dependency
    injection framework
    

    View Slide

25. public class RealBillingService implements BillingService {
    private final CreditCardProcessor processor;
    private final TransactionLog transactionLog;
    @Inject
    public RealBillingService(CreditCardProcessor processor,
    TransactionLog transactionLog) {
    this.processor = processor;
    this.transactionLog = transactionLog;
    }
    }
    Injector injector = Guice.createInjector(new BillingModule());
    BillingService billingService = injector.getInstance(
    BillingService.class
    );
    

    View Slide

26. What if you need multiple
    instance with different
    dependencies?
    — Skeptical Beau
    

    View Slide

27. That never happens but if
    it does there are ways.
    — Beau's entirely unconvincing friend
    

    View Slide

28. Sorry R.
    (for the record, I should have listened to him...)
    

    View Slide

29. Bring this back to PHP!
    where $this = IoC/DI
    

    View Slide

30. •
    

    View Slide

31. Substrate
    IoC/DI Container for PHP
    

    View Slide

32. Stones
    .. instead of Beans
    

    View Slide

33. Explicit Wiring
    PHP Configuration
    

    View Slide

34. $context->add('configuration', array(
    'className' => 'dd_configuration_PropertiesConfiguration',
    'constructorArgs' => array(
    'locations' => array(
    'lithe_base.properties',
    'app.properties',
    'app.site.properties',
    ),
    ),
    ));
    $context->add('placeholderConfigurer', array(
    'className' => 'substrate_DdConfigurationPlaceholderConfigurer',
    'constructorArgs' => array(
    'configuration' => $context->ref('configuration'),
    ),
    ));
    $context->add('logFactory', array(
    'className' => 'dd_logging_LogFactory',
    ));
    

    View Slide

35. Autowiring
    

    View Slide

36. foreach ($constructor->getParameters() as $reflectionParamter) {
    $constructorArgumentName = $reflectionParamter->getName();
    $paramClass = $reflectionParamter->getClass();
    if ($paramClass) {
    $paramClassName = $paramClass->getName();
    foreach ($this->stoneInstances as $testStone) {
    if ($testStone instanceof $paramClassName) {
    $constructorArgs[] = $testStone;
    break;
    }
    }
    }
    }
    

    View Slide

37. class dd_logging_FileLogDriver {
    public function __construct($filename) { /* .. */ }
    }
    class dd_logging_LogFactory {
    public function __construct(dd_logging_FileLogDriver $logger) { /* .. */ }
    }
    $context->add('logger', array(
    'className' => 'dd_logging_FileLogDriver',
    'constructorArgs' => array(
    'filename' => __DIR__.'/app.log',
    ),
    ));
    $context->add('logFactory', array(
    'className' => 'dd_logging_LogFactory',
    ));
    

    View Slide

38. Symfony
    PHP port of Spring
    

    View Slide

39. Symfony DIC
    Dependency Injection Component
    

    View Slide

40. Flexible
    

    View Slide

41. Compiler Passes!
    

    View Slide

42. COMPILED
    

    View Slide

43. View Slide

44. k.php
    

    View Slide

45. class ImportantService {
    private $logger;
    public function __construct($logger) {
    $this->logger = $logger;
    }
    public function doImportantTask() {
    $this
    ->logger
    ->info('Did important task!');
    }
    }
    

    View Slide

46. # k.php
    class ImportantService { /* ... */ }
    $fileLogDriver = new FileLogDriver(__DIR__.'/app.log');
    $logger = new Logger($fileLogDriver);
    $importantService = new ImportantService($logger);
    $importantService->doImportantTask();
    

    View Slide

47. # services.yml
    services:
    fileLogDriver:
    class: 'FileLogDriver'
    arguments: ['%kernel.root_dir%/app.log']
    logger:
    class: 'Logger'
    arguments: ['@fileLogDriver']
    importantService:
    class: 'ImportantService'
    arguments: ['@logger']
    $importantService = $container->get('importantService');
    $importantService->doImportantTask();
    

    View Slide

48. 
    
    
    
    
    %kernel.root_dir%/app.log
    
    
    
    
    
    
    
    
    
    $importantService = $container->get('importantService');
    $importantService->doImportantTask();
    

    View Slide

49. $container = new Pimple\Container();
    $container['fileLogDriver'] = function () {
    return new FileLogDriver(__DIR__.'/app.log');
    };
    $container['logger'] = function ($c) {
    return new Logger($c['fileLogDriver']);
    };
    $container['importantService'] = function ($c) {
    return new ImportantService($c['logger']);
    };
    $importantService = $container['importantService'];
    $importantService->doImportantTask();
    

    View Slide

50. $container = new Illuminate\Container\Container();
    $container->singleton('fileLogDriver', function ($c) {
    return new FileLogDriver(__DIR__.'/app.log');
    });
    $container->singleton('logger', function ($c) {
    return new Logger($c->make('fileLogDriver'));
    });
    $container->singleton('importantService', function ($c) {
    return new ImportantService($c->make('logger'));
    });
    $importantService = $container->make('importantService');
    $importantService->doImportantTask();
    

    View Slide

51. $container = new Illuminate\Container\Container();
    $container->singleton(FileLogDriver::class, function ($c) {
    return new FileLogDriver(__DIR__.'/app.log');
    });
    $container->singleton(Logger::class, function ($c) {
    return new Logger($c->make(FileLogDriver::class));
    });
    $container->singleton(ImportantService::class, function ($c) {
    return new ImportantService($c->make(Logger::class));
    });
    $importantService = $container->make(ImportantService::class);
    $importantService->doImportantTask();
    

    View Slide

52. Using class names for services is brilliant
    

    View Slide

53. foreach ($constructor->getParameters() as $reflectionParamter) {
    $constructorArgumentName = $reflectionParamter->getName();
    $paramClass = $reflectionParamter->getClass();
    if ($paramClass) {
    $paramClassName = $paramClass->getName();
    foreach ($this->stoneInstances as $testStone) {
    if ($testStone instanceof $paramClassName) {
    $constructorArgs[] = $testStone;
    break;
    }
    }
    }
    }
    

    View Slide

54. foreach ($constructor->getParameters() as $reflectionParamter) {
    $constructorArgumentName = $reflectionParamter->getName();
    $paramClass = $reflectionParamter->getClass();
    if ($paramClass) {
    $paramClassName = $paramClass->getName();
    $found = false;
    foreach ($this->stoneInstances as $testStone) {
    if ($testStone instanceof $paramClassName) {
    $constructorArgs[] = $testStone;
    $found = true;
    break;
    }
    }
    if (! $found) {
    $constructorArgs[] = $this->make($paramClassName);
    }
    }
    }
    

    View Slide

55. $container = new Illuminate\Container\Container();
    $container->singleton(FileLogDriver::class, function ($c) {
    return new FileLogDriver(__DIR__.'/app.log');
    });
    $container->singleton(Logger::class, function ($c) {
    return new Logger($c->make(FileLogDriver::class));
    });
    $container->singleton(ImportantService::class, function ($c) {
    return new ImportantService($c->make(Logger::class));
    });
    $importantService = $container->make(ImportantService::class);
    $importantService->doImportantTask();
    

    View Slide

56. $container = new Illuminate\Container\Container();
    $container->singleton(FileLogDriver::class, function ($c) {
    return new FileLogDriver(__DIR__.'/app.log');
    });
    $container->singleton(Logger::class, function ($c) {
    return new Logger($c->make(FileLogDriver::class));
    });
    $importantService = $container->make(ImportantService::class);
    $importantService->doImportantTask();
    

    View Slide

57. $container = new Illuminate\Container\Container();
    $container->singleton(FileLogDriver::class, function ($c) {
    return new FileLogDriver(__DIR__.'/app.log');
    });
    $importantService = $container->make(ImportantService::class);
    $importantService->doImportantTask();
    

    View Slide

58. Binding Primitives
    

    View Slide

59. $container = new Illuminate\Container\Container();
    $container
    ->when(FileLogDriver::class)
    ->needs('$filename')
    ->give(__DIR__.'/app.log');
    $importantService = $container->make(ImportantService::class);
    $importantService->doImportantTask();
    

    View Slide

60. Change
    

    View Slide

61. class ImportantService {
    private $logger;
    public function __construct($logger) {
    $this->logger = $logger;
    }
    public function doImportantTask() {
    $this
    ->logger
    ->info('Did important task!');
    }
    }
    

    View Slide

62. class Connection {
    public function execute() { /* ... */ }
    }
    

    View Slide

63. class ImportantService {
    private $logger;
    private $connection;
    public function __construct($logger, $connection) {
    $this->logger = $logger;
    $this->connection = $connection;
    }
    public function doImportantTask() {
    $this->connection->execute();
    $this
    ->logger
    ->info('Did important task!');
    }
    }
    

    View Slide

64. # k.php
    class Connection { /* ... */ }
    class ImportantService { /* ... */ }
    $fileLogDriver = new FileLogDriver(__DIR__.'/app.log');
    $logger = new Logger($fileLogDriver);
    $connection = new Connection();
    $importantService = new ImportantService(
    $logger,
    $connection
    );
    $importantService->doImportantTask();
    

    View Slide

65. # services.yml
    services:
    fileLogDriver:
    class: 'FileLogDriver'
    arguments: ['%kernel.root_dir%/app.log']
    logger:
    class: 'Logger'
    arguments: ['@fileLogDriver']
    importantService:
    class: 'ImportantService'
    arguments: ['@logger']
    $importantService = $container->get('importantService');
    $importantService->doImportantTask();
    

    View Slide

66. # services.yml
    services:
    fileLogDriver:
    class: 'FileLogDriver'
    arguments: ['%kernel.root_dir%/app.log']
    logger:
    class: 'Logger'
    arguments: ['@fileLogDriver']
    connection:
    class: 'Connection'
    importantService:
    class: 'ImportantService'
    arguments: ['@logger', '@connection']
    $importantService = $container->get('importantService');
    $importantService->doImportantTask();
    

    View Slide

67. 
    
    
    
    
    %kernel.root_dir%/app.log
    
    
    
    
    
    
    
    
    
    $importantService = $container->get('importantService');
    $importantService->doImportantTask();
    

    View Slide

68. 
    
    
    
    
    %kernel.root_dir%/app.log
    
    
    
    
    
    
    
    
    
    
    
    $importantService = $container->get('importantService');
    $importantService->doImportantTask();
    

    View Slide

69. $container = new Pimple\Container();
    $container['fileLogDriver'] = function () {
    return new FileLogDriver(__DIR__.'/app.log');
    };
    $container['logger'] = function ($c) {
    return new Logger($c['fileLogDriver']);
    };
    $container['importantService'] = function ($c) {
    return new ImportantService($c['logger']);
    };
    $importantService = $container['importantService'];
    $importantService->doImportantTask();
    

    View Slide

70. $container = new Pimple\Container();
    $container['fileLogDriver'] = function () {
    return new FileLogDriver(__DIR__.'/app.log');
    };
    $container['logger'] = function ($c) {
    return new Logger($c['fileLogDriver']);
    };
    $container['connection'] = function ($c) {
    return new Connection();
    };
    $container['importantService'] = function ($c) {
    return new ImportantService(
    $c['logger'],
    $c['connection']
    );
    };
    $importantService = $container['importantService'];
    $importantService->doImportantTask();
    

    View Slide

71. $container = new Illuminate\Container\Container();
    $container
    ->when(FileLogDriver::class)
    ->needs('$filename')
    ->give(__DIR__.'/app.log');
    $importantService = $container->make(ImportantService::class);
    $importantService->doImportantTask();
    

    View Slide

72. $container = new Illuminate\Container\Container();
    $container
    ->when(FileLogDriver::class)
    ->needs('$filename')
    ->give(__DIR__.'/app.log');
    $importantService = $container->make(ImportantService::class);
    $importantService->doImportantTask();
    Nothing But Win!
    

    View Slide

73. XML and YAML fatigue
    — Beau, That Podcast episode 32
    

    View Slide

74. Pros
    

    View Slide

75. Amazing Developer Experience
    

    View Slide

76. Great for heavy refactoring sessions
    

    View Slide

77. More code writing
    Less configuration wrangling
    

    View Slide

78. Magic
    

    View Slide

79. Cons
    

    View Slide

80. Performance
    

    View Slide

81. Difficult to optimize
    

    View Slide

82. Magic
    

    View Slide

83. View Slide

84. Best of Both Worlds?
    

    View Slide

85. Symfony
    +
    Autowiring
    

    View Slide

86. Service Autowiring
    Symfony 2.8
    

    View Slide

87. # app/config/services.yml
    services:
    service1:
    class: AppBundle\Service\Service1
    service2:
    class: AppBundle\Service\Service2
    arguments: ['@service1']
    

    View Slide

88. # app/config/services.yml
    services:
    service2:
    class: AppBundle\Service\Service2
    autowire: true
    

    View Slide

89. What's the point?
    — Entitled Beau
    

    View Slide

90. kutny/autowiring-bundle
    

    View Slide

91. services:
    service2:
    class: AppBundle\Service\Service2
    autowire: true
    

    View Slide

92. services:
    service2:
    class: AppBundle\Service\Service2
    

    View Slide

93. dunglas/action-bundle
    Symfony controllers, redesigned.
    

    View Slide

94. Scans directories
    Dynamically generates services
    with class names as the ID
    

    View Slide

95. class Homepage
    {
    private $router;
    private $twig;
    public function __construct(RouterInterface $router, \Twig_Environment $twig)
    {
    $this->router = $router;
    $this->twig = $twig;
    }
    /**
    * @Route("/myaction", name="my_action")
    */
    public function __invoke(Request $request)
    {
    if (!$request->isMethod('GET')) {
    return new RedirectResponse($this->router->generateUrl('my_action'), 301);
    }
    return new Response($this->twig->render('mytemplate.html.twig'));
    }
    }
    

    View Slide

96. Despite the name of the package...
    It's not limited to actions!
    

    View Slide

97. YAY!
    Performance! Optimization!
    Developer Experience!
    

    View Slide

98. Symfony 3.3
    

    View Slide

99. #20264 – Symfony 3.3
    Optional class for class named services
    @hason
    

    View Slide

100. # before
     services:
     Vendor\Namespace\Class:
     class: Vendor\Namespace\Class
     autowire: true
     # after
     services:
     Vendor\Namespace\Class:
     autowire: true
     

     View Slide

101. #21071 – Symfony 3.3
     Configurable defaults for public, tags and autowiring
     @nicolas-grekas
     

     View Slide

102. # before
     services:
     Foo:
     public: false
     autowire: true
     Bar:
     public: false
     autowire: true
     # after
     services:
     _defaults:
     public: false
     autowire: true
     Foo: ~
     Bar: ~
     

     View Slide

103. #21289 – Symfony 3.3
     PSR4-based discovery and registration
     @nicolas-grekas
     

     View Slide

104. services:
     App\:
     # relative to the current file
     resources: ../src/{Controller,Command}
     # or any other attributes
     autowire: true
     

     View Slide

105. #21530 – Symfony 3.3
     _instanceof: local interface-defined configs
     @nicolas-grekas
     

     View Slide

106. services:
     _defaults:
     public: false
     _instanceof:
     Symfony\Component\Console\Command\Command:
     tags: ['console.command']
     public: true # commands must be public
     Twig_ExtensionInterface:
     tags: ['twig.extension']
     Symfony\Component\EventDispatcher\EventSubscriberInterface:
     tags: ['kernel.event_subscriber']
     App\:
     resource: ../src/{Action,Command,EventSubscriber,Twig}
     

     View Slide

107. #22234 – Symfony 3.3
     automatic _instanceof configuration
     @weaverryan
     

     View Slide

108. # before
     services:
     _defaults:
     autowire: true
     _instanceof:
     Symfony\Component\EventDispatcher\EventSubscriberInterface:
     tags: [kernel.event_subscriber]
     # service using the above tag
     AppBundle\EventListener\CheckRequirementsSubscriber: ~
     # after
     services:
     _defaults:
     autowire: true
     autoconfigure: true
     # service using the auto_configure_instanceof functionality
     AppBundle\EventListener\CheckRequirementsSubscriber: ~
     

     View Slide

109. #21383 – Symfony 3.3
     Named arguments
     @dunglas
     

     View Slide

110. class NewsletterManager
     {
     private $logger;
     private $em;
     private $apiKey;
     public function __construct(
     LoggerInterface $logger,
     EntityManager $em,
     $apiKey
     ) {
     $this->logger = $logger;
     $this->em = $em;
     $this->apiKey = $apiKey;
     }
     }
     

     View Slide

111. # New awesome syntax
     services:
     _defaults: { autowire: true }
     Acme\NewsletterManager: { $apiKey: "%mandrill_api_key%" }
     # Alternative (more traditional) syntax
     services:
     newsletter_manager:
     class: Acme\NewsletterManager
     arguments:
     $apiKey: "%mandrill_api_key%"
     autowire: true
     

     View Slide

112. #21771 – Symfony 3.3
     "controller.service_arguments" tag
     inject services into actions
     @nicolas-grekas
     

     View Slide

113. class Home {
     /**
     * @Route("/myaction", name="my_action")
     */
     public function myAction(Request $request, Router $router, Twig $twig) {
     if (!$request->isMethod('GET')) {
     return new RedirectResponse($router->generateUrl('my_action'), 301);
     }
     return new Response($twig->render('mytemplate.html.twig'));
     }
     }
     

     View Slide

114. Symfony Flex!
     

     View Slide

115. services:
     _defaults:
     autowire: true
     autoconfigure: true
     public: false
     App\:
     resource: '../../src/{Command,Form,EventSubscriber,Twig,Voter}'
     App\Controller\:
     resource: '../../src/Controller'
     public: true
     tags: ['controller.service_arguments']
     

     View Slide

116. Real Life
     

     View Slide

117. src/Controller/
     ├── AccountBusinessFirstTimeSetupController.php
     ├── Businesses
     │ ├── Audiences
     │ │ └── Connect
     │ │ └── ConnectTwitterAudienceController.php
     │ ├── AudiencesController.php
     │ ├── Stores
     │ │ └── Connect
     │ │ └── ConnectEtsyStoreController.php
     │ └── StoresController.php
     ├── DashboardController.php
     ├── PricingController.php
     ├── SecurityController.php
     └── UserController.php
     

     View Slide

118. class SecurityController extends Controller
     {
     /**
     * @Route("/login", name="login", methods={"GET"})
     */
     public function login(AuthenticationUtils $authUtils)
     {
     return $this->render('security/login.html.twig', [
     'last_username' => $authUtils->getLastUsername(),
     'error' => $authUtils->getLastAuthenticationError(),
     ]);
     }
     }
     

     View Slide

119. class ConnectEtsyStoreController extends Controller
     {
     private $serverFactory;
     private $oauthRepository;
     public function __construct(
     EtsyOauthServerFactory $serverFactory,
     EtsyOauthRepository $oauthRepository,
     ) {
     $this->serverFactory = $serverFactory;
     $this->oauthRepository = $oauthRepository;
     }
     /**
     * @Route("/account/businesses/{business}/stores/connect/etsy", name="etsy_store_connect")
     */
     public function connect(Request $request, SessionInterface $session, Business $business)
     {
     $server = $this->serverFactory->create($business);
     $temporaryCredentials = $server->getTemporaryCredentials();
     $session->set('etsyoauth_token', $temporaryCredentials->getIdentifier());
     $session->set('etsyoauth_token_secret', $temporaryCredentials->getSecret());
     return $this->redirect($server->getAuthorizationUrl($temporaryCredentials));
     }
     }
     

     View Slide

120. src/Doctrine/
     └── SchemaNamespaceFixListener.php
     

     View Slide

121. src/EventSubscriber/
     ├── BusinessSubscriptionOnboardingProcessSubscriber.php
     └── BusinessSubscriptionOnboardingSubscriber.php
     

     View Slide

122. src/Integration/Store/Etsy/
     ├── EtsyApiClient
     │ ├── EtsyApiClient.php
     │ ├── Requests
     │ │ ├── Associations.php
     │ │ ├── Listing
     │ │ │ ├── FindAllShopListingsActive.php
     │ │ │ └── FindAllShopSectionListingsActive.php
     │ │ ├── Pagination.php
     │ │ ├── RenderedRequest.php
     │ │ ├── Request.php
     │ │ └── Shop
     │ │ └── FindAllShopSections.php
     │ └── Response.php
     └── Oauth
     ├── EtsyOauthServer.php
     └── EtsyOauthServerFactory.php
     

     View Slide

123. src/Validator/
     ├── UniqueBusinessUsername.php
     ├── UniqueBusinessUsernameValidator.php
     ├── UniqueUserEmailAddress.php
     ├── UniqueUserEmailAddressValidator.php
     ├── UniqueUserUsername.php
     └── UniqueUserUsernameValidator.php
     

     View Slide

124. class UniqueBusinessUsernameValidator extends ConstraintValidator
     {
     /**
     * @var BusinessRepository
     */
     private $businessRepository;
     public function __construct(BusinessRepository $businessRepository)
     {
     $this->businessRepository = $businessRepository;
     }
     public function validate($value, Constraint $constraint)
     {
     $business = $this->businessRepository->findByUsername($value);
     if (is_null($business)) {
     return;
     }
     $this->context->buildViolation($constraint->message)
     ->setParameter('{{ value }}', $value)
     ->addViolation();
     }
     }
     

     View Slide

125. 49 classes
     

     View Slide

126. services:
     _defaults:
     autowire: true
     autoconfigure: true
     App\:
     resource: '../src/*'
     exclude: '../src/{DependencyInjection,Entity,Migrations,Tests,Kernel.php}'
     App\Controller\:
     resource: '../src/Controller'
     tags: ['controller.service_arguments']
     

     View Slide

127. # ...
     App\Integration\Store\Etsy\EtsyApiClient\EtsyApiClient:
     arguments:
     $consumerKey: '%env(ETSYOAUTH_CONSUMER_KEY)%'
     $consumerSecret: '%env(ETSYOAUTH_CONSUMER_SECRET)%'
     App\Integration\Store\Etsy\Oauth\EtsyOauthServerFactory:
     arguments:
     $consumerKey: '%env(ETSYOAUTH_CONSUMER_KEY)%'
     $consumerSecret: '%env(ETSYOAUTH_CONSUMER_SECRET)%'
     App\Controller\Businesses\Audiences\Connect\ConnectTwitterAudienceController:
     arguments:
     $consumerKey: '%env(TWITTEROAUTH_CONSUMER_KEY)%'
     $consumerSecret: '%env(TWITTEROAUTH_CONSUMER_SECRET)%'
     App\Doctrine\SchemaNamespaceFixListener:
     tags:
     - { name: doctrine.event_subscriber, connection: default }
     

     View Slide

128. View Slide

129. View Slide

130. Interface Binding
     

     View Slide

131. class Logger {
     public function __construct(FileLogDriver $fileLogDriver) { /* ... */ }
     }
     class FileLogDriver {
     public function info($message) { /* ... */ }
     }
     

     View Slide

132. class Logger {
     public function __construct(Logger $logger) { /* ... */ }
     }
     interface LogDriver {
     public function info($message);
     }
     class FileLogDriver implements LogDriver {
     public function info($message) { /* ... */ }
     }
     

     View Slide

133. $container = new Illuminate\Container\Container();
     $container
     ->when(FileLogDriver::class)
     ->needs('$filename')
     ->give(__DIR__.'/app.log');
     $importantService = $container->make(ImportantService::class);
     $importantService->doImportantTask();
     

     View Slide

134. $container = new Illuminate\Container\Container();
     $container
     ->when(FileLogDriver::class)
     ->needs('$filename')
     ->give(__DIR__.'/app.log');
     $container->bind(LogDriver::class, FileLogDriver::class);
     $importantService = $container->make(ImportantService::class);
     $importantService->doImportantTask();
     

     View Slide

135. $container = new Illuminate\Container\Container();
     $container
     ->when(FileLogDriver::class)
     ->needs('$filename')
     ->give(__DIR__.'/app.log');
     $container->bind(LogDriver::class, SylogLogger::class);
     $importantService = $container->make(ImportantService::class);
     $importantService->doImportantTask();
     

     View Slide

136. But what about multiple
     instances with different
     configurations?
     — Beau from like 10 years ago
     

     View Slide

137. Contextual Binding
     

     View Slide

138. class NullLogDriver implements LogDriver {
     public function info($message) {
     // noop
     }
     }
     

     View Slide

139. class UnimportantService {
     public function __construct(Logger $logger) { /* .. */ }
     }
     

     View Slide

140. # k.php
     class Connection { /* ... */ }
     class ImportantService { /* ... */ }
     class UnimportantService { /* ... */ }
     $fileLogDriver = new FileLogDriver(__DIR__.'/app.log');
     $fileLogDriver = new Logger($fileLogDriver);
     $connection = new Connection();
     $importantService = new ImportantService(
     $fileLogDriver,
     $connection
     );
     $nullLogDriver = new NullLogDriver();
     $nullLogger = new Logger($nullLogDriver);
     $unimportantService = new UnimportantService(
     $nullLogger
     );
     

     View Slide

141. $container = new Illuminate\Container\Container();
     $container
     ->when(FileLogDriver::class)
     ->needs('$filename')
     ->give(__DIR__.'/app.log');
     $container->bind(LogDriver::class, FileLogDriver::class);
     $importantService = $container->make(ImportantService::class);
     $unimportantService = $container->make(UnimportantService::class);
     

     View Slide

142. $container = new Illuminate\Container\Container();
     $container
     ->when(FileLogDriver::class)
     ->needs('$filename')
     ->give(__DIR__.'/app.log');
     $container->bind(LogDriver::class, FileLogDriver::class);
     $container
     ->when(UnimportantService::class)
     ->needs(LogDriver::class)
     ->give(function ($c) {
     $nullLogDriver = $c->make(NullLogDriver::class);
     return new Logger($nullLogDriver);
     });
     $importantService = $container->make(ImportantService::class);
     $unimportantService = $container->make(UnimportantService::class);
     

     View Slide

143. View Slide

144. Still not convinced?
     

     View Slide

145. Configuration ends up being
     exceptions
     

     View Slide

146. You can always wire manually if
     something breaks
     

     View Slide

147. Give it a try. :)
     

     View Slide

148. Thanks!
     beausimensen.com • @beausimensen
     thatpodcast.io • @thatpodcast
     astrocasts.com • @astrocasts
     

     View Slide