Learn to Stop Wiring and Love Laravel's Container Lone Star PHP 2017

You've heard about dependency injection and inversion of control. Everything seems easy at first and you've found a container or two to help make your life easier. Until it isn't anymore. Suddenly you've found yourself managing complicated YAML, XML, or PHP container configurations. Making any change to your classes dependencies seems like a chore and any time you add a new class to the system you dread the inevitable configuration container configuration wiring blues.

Life doesn't have to be this way! In fact, life isn't this way for anyone who uses an autowiring container like Laravel's. Far from the most publicly marketed component, Illuminate\Container handles a lot of the magic that makes Laravel so much fun to use. Find out how you can use Laravel's container in almost any project! See how autowiring can free your mind from having to manually configure ever little dependency. Learn how you, too, can learn to stop wiring your dependency injection container and love Laravel's container!

Transcript

1. Learn to Stop Wiring
   and Love Laravel's
   Container
   joind.in/talk/a7abc
   Beau Simensen • beau.io • @beausimensen
   

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2. Terminology
   

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3. History
   

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4. Implementations
   

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5. Future
   

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7. SOLID
   

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8. D
   Dependency Injection?
   

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9. D
   Dependency Inversion
   

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10. Inversion of
    Control
    

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11. Dependency
    Injection
    

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12. Service Locator
    

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

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

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

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16. 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) \ \ __/
    \____\______/
    

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17. Wiring
    

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18. 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']
    

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20. Spring Framework's
    IoC Container
    

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21. Beans
    

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22. Explicit Wiring
    

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23. XML > Annotations
    

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24. 
    
    class="org.springbyexample.di.app.Message">
    
    
    
    

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25. Google's Guice
    a lightweight dependency
    injection framework
    

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26. 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
    );
    

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

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

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

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

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31. •
    

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32. Substrate
    IoC/DI Container for PHP
    

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33. Stones
    .. instead of Beans
    

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34. Explicit Wiring
    PHP Configuration
    

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35. $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',
    ));
    

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36. Autowiring
    

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37. 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;
    }
    }
    }
    }
    

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

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39. Symfony
    PHP port of Spring
    

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40. Symfony DIC
    Dependency Injection Component
    

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41. Flexible
    

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42. Compiler Passes!
    

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43. COMPILED
    

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45. Symfony & Silex
    

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46. Subtly Painful
    

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47. k.php
    

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

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49. # k.php
    class ImportantService { /* ... */ }
    $fileLogger = new FileLoger(__DIR__.'/app.log');
    $loggerFactory = new LoggerFactory($fileLogger);
    $importantService = new ImportantService($loggerFactory);
    $importantService->doImportantTask();
    

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50. # services.yml
    services:
    fileLogger:
    class: 'FileLogger'
    arguments: ['%kernel.root_dir%/app.log']
    loggerFactory:
    class: 'LoggerFactory'
    arguments: ['@fileLogger']
    importantService:
    class: 'ImportantService'
    arguments: ['@loggerFactory']
    $importantService = $container->get('importantService');
    $importantService->doImportantTask();
    

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51. 
    
    
    
    
    %kernel.root_dir%/app.log
    
    
    
    
    
    
    
    
    
    $importantService = $container->get('importantService');
    $importantService->doImportantTask();
    

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52. $container = new Pimple\Container();
    $container['fileLogger'] = function () {
    return new FileLogger(__DIR__.'/app.log');
    };
    $container['loggerFactory'] = function ($c) {
    return new LoggerFactory($c['fileLogger']);
    };
    $container['importantService'] = function ($c) {
    return new ImportantService($c['loggerFactory']);
    };
    $importantService = $container['importantService'];
    $importantService->doImportantTask();
    

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53. $container = new Illuminate\Container\Container();
    $container->singleton('fileLogger', function ($c) {
    return new FileLogger(__DIR__.'/app.log');
    });
    $container->singleton('loggerFactory', function ($c) {
    return new LoggerFactory($c->make('loggerFactory'));
    });
    $container->singleton('importantService', function ($c) {
    return new ImportantService($c->make('loggerFactory'));
    });
    $importantService = $container->make('importantService');
    $importantService->doImportantTask();
    

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

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55. Using class names for
    services is brilliant
    

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56. 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;
    }
    }
    }
    }
    

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57. 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);
    }
    }
    }
    

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

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

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

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61. Binding Primitives
    

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

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63. Change
    

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

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

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

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67. # k.php
    class Connection { /* ... */ }
    class ImportantService { /* ... */ }
    $fileLogger = new FileLoger(__DIR__.'/app.log');
    $loggerFactory = new LoggerFactory($fileLogger);
    $connection = new Connection();
    $importantService = new ImportantService(
    $loggerFactory,
    $connection
    );
    $importantService->doImportantTask();
    

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68. # services.yml
    services:
    fileLogger:
    class: 'FileLogger'
    arguments: ['%kernel.root_dir%/app.log']
    loggerFactory:
    class: 'LoggerFactory'
    arguments: ['@fileLogger']
    importantService:
    class: 'ImportantService'
    arguments: ['@loggerFactory']
    $importantService = $container->get('importantService');
    $importantService->doImportantTask();
    

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69. # services.yml
    services:
    fileLogger:
    class: 'FileLogger'
    arguments: ['%kernel.root_dir%/app.log']
    loggerFactory:
    class: 'LoggerFactory'
    arguments: ['@fileLogger']
    connection:
    class: 'Connection'
    importantService:
    class: 'ImportantService'
    arguments: ['@loggerFactory', '@connection']
    $importantService = $container->get('importantService');
    $importantService->doImportantTask();
    

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70. 
    
    
    
    
    %kernel.root_dir%/app.log
    
    
    
    
    
    
    
    
    
    $importantService = $container->get('importantService');
    $importantService->doImportantTask();
    

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71. 
    
    
    
    
    %kernel.root_dir%/app.log
    
    
    
    
    
    
    
    
    
    
    
    $importantService = $container->get('importantService');
    $importantService->doImportantTask();
    

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72. $container = new Pimple\Container();
    $container['fileLogger'] = function () {
    return new FileLogger(__DIR__.'/app.log');
    };
    $container['loggerFactory'] = function ($c) {
    return new LoggerFactory($c['fileLogger']);
    };
    $container['importantService'] = function ($c) {
    return new ImportantService($c['loggerFactory']);
    };
    $importantService = $container['importantService'];
    $importantService->doImportantTask();
    

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73. $container = new Pimple\Container();
    $container['fileLogger'] = function () {
    return new FileLogger(__DIR__.'/app.log');
    };
    $container['loggerFactory'] = function ($c) {
    return new LoggerFactory($c['fileLogger']);
    };
    $container['connection'] = function ($c) {
    return new Connection();
    };
    $container['importantService'] = function ($c) {
    return new ImportantService(
    $c['loggerFactory'],
    $c['connection']
    );
    };
    $importantService = $container['importantService'];
    $importantService->doImportantTask();
    

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

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

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76. Wonderful Developer Experience
    

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

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78. It had major impact on
    design
    I didn't want to have to tackle
    configuration
    

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79. No more service
    identifiers
    Unless you want to use them
    

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80. Interface
    Binding
    

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81. class LoggerFactory {
    public function __construct(FileLogger $fileLogger) { /* ... */ }
    }
    class FileLogger {
    public function info($message) { /* ... */ }
    }
    

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82. class LoggerFactory {
    public function __construct(Logger $logger) { /* ... */ }
    }
    interface Logger {
    public function info($message);
    }
    class FileLogger implements Logger {
    public function info($message) { /* ... */ }
    }
    

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

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

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

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

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87. Contextual Binding
    

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88. class NullLogger implements Logger {
    public function info($message) {
    // noop
    }
    }
    

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89. class UnimportantService {
    public function __construct(LoggerFactory $loggerFactory) { /* .. */ }
    }
    

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90. # k.php
    class Connection { /* ... */ }
    class ImportantService { /* ... */ }
    class UnimportantService { /* ... */ }
    $fileLogger = new FileLoger(__DIR__.'/app.log');
    $fileLoggerFactory = new LoggerFactory($fileLogger);
    $connection = new Connection();
    $importantService = new ImportantService(
    $fileLoggerFactory,
    $connection
    );
    $nullLogger = new NullLogger();
    $nullLoggerFactory = new LoggerFactory($nullLogger)
    $unimportantService = new UnimportantService(
    $nullLoggerFactory
    );
    

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

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92. $container = new Illuminate\Container\Container();
    $container
    ->when(FileLogger::class)
    ->needs('$filename')
    ->give(__DIR__.'/app.log');
    $container->bind(Logger::class, FileLogger::class);
    $container
    ->when(UnimportantService::class)
    ->needs(LoggerFactory::class)
    ->give(function ($c) {
    $nullLogger = $c->make(NullLogger::class);
    return new LoggerFactory($nullLogger);
    });
    $importantService = $container->make(ImportantService::class);
    $unimportantService = $container->make(UnimportantService::class);
    

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94. Pros
    

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95. Amazing Developer Experience
    

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96. Great for heavy refactoring sessions
    

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97. More code writing
    Less configuration wrangling
    

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98. Magic
    

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99. Cons
    

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100. Performance
     

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101. Difficult to optimize
     

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102. Magic
     

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103. Best of Both
     Worlds?
     

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104. Symfony 2.8: Service
     Autowiring
     

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

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

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107. What's the point?
     — Entitled Beau
     

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108. kutny/autowiring-bundle
     

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

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

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111. Still have to define
     services and assign them
     a service identifier.
     

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112. #20264
     Optional class for class named services
     @hason
     

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

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114. Still have to define
     services.
     

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

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

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117. 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'));
     }
     }
     

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

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119. YAY!
     Performance!
     Optimization!
     

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120. Symfony Flex!
     

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121. ?
     Magic!
     

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122. A lot of experimentation in
     Dependency
     Injection
     

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123. Thanks!
     beau.io • @beausimensen
     thatpodcast.io • @thatpodcast
     @sensiolabs • @blackfireio
     joind.in/talk/a7abc
     

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