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
2. Terminology
3. History
4. Implementations
6. SOLID
7. D Dependency Injection?
8. D Dependency Inversion
9. Inversion of Control
10. Dependency Injection
11. Service Locator
12. Dependency Inversion .-- Dependency Injection | Inversion of Control --+ | `-- Service Locator
13. Dependency Inversion .-- Dependency Injection --. | | Inversion of Control --+--------------------------+-- Container | | `-- Service Locator -------' Dependency Injection Container Inversion of Control Container Service Container
14. Dependency Inversion .-- Dependency Injection --. | | Inversion of Control --+--------------------------+-- Container | | `-- Service Locator -------' Dependency Injection Container Inversion of Control Container Service Container Container
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) \ \ __/ \____\______/
16. Wiring
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']
19. Spring Framework's IoC Container
20. Beans
21. Explicit Wiring
22. XML > Annotations
23. <?xml version="1.0" encoding="UTF-8"?> <beans> <bean id="message" class="org.springbyexample.di.app.Message"> <property name="message" value="Spring is fun." /> </bean> </beans>
24. Google's Guice a lightweight dependency injection framework
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 );
26. What if you need multiple instance with different dependencies? — Skeptical Beau
27. That never happens but if it does there are ways. — Beau's entirely unconvincing friend
28. Sorry R. (for the record, I should have listened to him...)
29. Bring this back to PHP! where $this = IoC/DI
30. •
31. Substrate IoC/DI Container for PHP
32. Stones .. instead of Beans
33. Explicit Wiring PHP Configuration
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'), ), )); $context->add('logFactory', array( 'className' => 'dd_logging_LogFactory', ));
35. Autowiring
36. foreach ($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[] = $testStone; break; } } } }
37. class dd_logging_FileLogDriver { public function __construct($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', ));
38. Symfony PHP port of Spring
39. Symfony DIC Dependency Injection Component
40. Flexible
41. Compiler Passes!
42. COMPILED
44. k.php
45. class ImportantService { private $logger; public function __construct($logger) { $this->logger = $logger; } public function doImportantTask() { $this ->logger ->info('Did important task!'); } }
46. # k.php class ImportantService { /* ... */ } $fileLogDriver = new FileLogDriver(__DIR__.'/app.log'); $logger = new Logger($fileLogDriver); $importantService = new ImportantService($logger); $importantService->doImportantTask();
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();
48. <!-- app/config/services.xml --> <?xml version="1.0" encoding="UTF-8" ?> <container> <services> <service id="fileLogDriver" class="FileLogDriver"> <argument>%kernel.root_dir%/app.log</argument> </service> <service id="logger" class="Logger"> <argument type="service" id="fileLogDriver" /> </service> <service id="importantService" class="ImportantService"> <argument type="service" id="logger" /> </service> </services> </container> $importantService = $container->get('importantService'); $importantService->doImportantTask();
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();
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();
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); $importantService->doImportantTask();
52. Using class names for services is brilliant
53. foreach ($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[] = $testStone; break; } } } }
54. foreach ($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); } } }
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();
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();
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();
58. Binding Primitives
59. $container = new Illuminate\Container\Container(); $container ->when(FileLogDriver::class) ->needs('$filename') ->give(__DIR__.'/app.log'); $importantService = $container->make(ImportantService::class); $importantService->doImportantTask();
60. Change
61. class ImportantService { private $logger; public function __construct($logger) { $this->logger = $logger; } public function doImportantTask() { $this ->logger ->info('Did important task!'); } }
62. class Connection { public function execute() { /* ... */ } }
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!'); } }
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();
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();
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();
67. <!-- app/config/services.xml --> <?xml version="1.0" encoding="UTF-8" ?> <container> <services> <service id="fileLogDriver" class="FileLogDriver"> <argument>%kernel.root_dir%/app.log</argument> </service> <service id="logger" class="Logger"> <argument type="service" id="fileLogDriver" /> </service> <service id="importantService" class="ImportantService"> <argument type="service" id="logger" /> </service> </services> </container> $importantService = $container->get('importantService'); $importantService->doImportantTask();
68. <!-- app/config/services.xml --> <?xml version="1.0" encoding="UTF-8" ?> <container> <services> <service id="fileLogDriver" class="FileLogDriver"> <argument>%kernel.root_dir%/app.log</argument> </service> <service id="logger" class="Logger"> <argument type="service" id="fileLogDriver" /> </service> <service id="connection" class="Connection" /> <service id="importantService" class="ImportantService"> <argument type="service" id="logger" /> <argument type="service" id="connection" /> </service> </services> </container> $importantService = $container->get('importantService'); $importantService->doImportantTask();
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();
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();
71. $container = new Illuminate\Container\Container(); $container ->when(FileLogDriver::class) ->needs('$filename') ->give(__DIR__.'/app.log'); $importantService = $container->make(ImportantService::class); $importantService->doImportantTask();
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!
73. XML and YAML fatigue — Beau, That Podcast episode 32
74. Pros
75. Amazing Developer Experience
76. Great for heavy refactoring sessions
77. More code writing Less configuration wrangling
78. Magic
79. Cons
80. Performance
81. Difficult to optimize
82. Magic
84. Best of Both Worlds?
85. Symfony + Autowiring
86. Service Autowiring Symfony 2.8
87. # app/config/services.yml services: service1: class: AppBundle\Service\Service1 service2: class: AppBundle\Service\Service2 arguments: ['@service1']
88. # app/config/services.yml services: service2: class: AppBundle\Service\Service2 autowire: true
89. What's the point? — Entitled Beau
90. kutny/autowiring-bundle
91. services: service2: class: AppBundle\Service\Service2 autowire: true
92. services: service2: class: AppBundle\Service\Service2
93. dunglas/action-bundle Symfony controllers, redesigned.
94. Scans directories Dynamically generates services with class names as the ID
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')); } }
96. Despite the name of the package... It's not limited to actions!
97. YAY! Performance! Optimization! Developer Experience!
98. Symfony 3.3
99. #20264 – Symfony 3.3 Optional class for class named services @hason
100. # before services: Vendor\Namespace\Class: class: Vendor\Namespace\Class autowire: true # after services: Vendor\Namespace\Class: autowire: true
101. #21071 – Symfony 3.3 Configurable defaults for public, tags and autowiring @nicolas-grekas
102. # before services: Foo: public: false autowire: true Bar: public: false autowire: true # after services: _defaults: public: false autowire: true Foo: ~ Bar: ~
103. #21289 – Symfony 3.3 PSR4-based discovery and registration @nicolas-grekas
104. services: App\: # relative to the current file resources: ../src/{Controller,Command} # or any other attributes autowire: true
105. #21530 – Symfony 3.3 _instanceof: local interface-defined configs @nicolas-grekas
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}
107. #22234 – Symfony 3.3 automatic _instanceof configuration @weaverryan
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: ~
109. #21383 – Symfony 3.3 Named arguments @dunglas
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; } }
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
112. #21771 – Symfony 3.3 "controller.service_arguments" tag inject services into actions @nicolas-grekas
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')); } }
114. Symfony Flex!
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']
116. Real Life
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
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(), ]); } }
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)); } }
120. src/Doctrine/ └── SchemaNamespaceFixListener.php
121. src/EventSubscriber/ ├── BusinessSubscriptionOnboardingProcessSubscriber.php └── BusinessSubscriptionOnboardingSubscriber.php
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
123. src/Validator/ ├── UniqueBusinessUsername.php ├── UniqueBusinessUsernameValidator.php ├── UniqueUserEmailAddress.php ├── UniqueUserEmailAddressValidator.php ├── UniqueUserUsername.php └── UniqueUserUsernameValidator.php
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(); } }
125. 49 classes
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']
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 }
130. Interface Binding
131. class Logger { public function __construct(FileLogDriver $fileLogDriver) { /* ... */ } } class FileLogDriver { public function info($message) { /* ... */ } }
132. class Logger { public function __construct(Logger $logger) { /* ... */ } } interface LogDriver { public function info($message); } class FileLogDriver implements LogDriver { public function info($message) { /* ... */ } }
133. $container = new Illuminate\Container\Container(); $container ->when(FileLogDriver::class) ->needs('$filename') ->give(__DIR__.'/app.log'); $importantService = $container->make(ImportantService::class); $importantService->doImportantTask();
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();
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); $importantService->doImportantTask();
136. But what about multiple instances with different configurations? — Beau from like 10 years ago
137. Contextual Binding
138. class NullLogDriver implements LogDriver { public function info($message) { // noop } }
139. class UnimportantService { public function __construct(Logger $logger) { /* .. */ } }
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 );
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);
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);
144. Still not convinced?
145. Configuration ends up being exceptions
146. You can always wire manually if something breaks
147. Give it a try. :)
148. Thanks! beausimensen.com • @beausimensen thatpodcast.io • @thatpodcast astrocasts.com • @astrocasts