依存関係のコントロール / Dependency Control

PHP Conference 2022 でソフトウェア開発における依存をどのように制御するかについてお話ししました。

この資料を使ったトークが YouTube にアップロードされています。
トークURL: https://youtu.be/0Y7ew4FHdO4

セッションの概要など詳しくはｺﾁﾗ→https://fortee.jp/phpcon-2022/proposal/2a07ae7f-0b02-42d5-a5f3-53d397a7dcfc

◆ URL
トークURL: https://youtu.be/0Y7ew4FHdO4
チャンネル登録: https://www.youtube.com/c/narusemi?sub_confirmation=1
Twitter: https://twitter.com/nrslib

Transcript

1. View Slide

2. View Slide

3. View Slide

4. 他に頼って存在、または生活すること。
   デジタル大辞泉
   

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11. View Slide

12. View Slide

13. View Slide

14. View Slide

15. $msg = "hello";
    var_dump($msg);
    

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16. class Foo {
    public function greet() {
    echo "hello";
    }
    }
    $foo = new Foo();
    $foo->greet();
    

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17. class Foo {
    private readonly Bar $bar;
    public function __construct(Bar $bar) {
    $this->bar = $bar;
    }
    public function greet() {
    echo "hello " . $this->bar->getName();
    }
    }
    class Bar {
    private readonly string $name;
    public function __construct(string $name) {
    $this->name = $name;
    }
    public function getName(): string
    {
    return $this->name;
    }
    }
    $bar = new Bar("nrs");
    $foo = new Foo($bar);
    $foo->greet();
    

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18. class Foo {
    private readonly Bar $bar;
    public function __construct(Bar $bar) {
    $this->bar = $bar;
    }
    public function greet() {
    echo "hello " . $this->bar->getName();
    }
    }
    class Bar {
    private readonly string $name;
    public function __construct(string $name) {
    $this->name = $name;
    }
    public function getName(): string
    {
    return $this->name;
    }
    }
    $bar = new Bar("nrs");
    $foo = new Foo($bar);
    $foo->greet();
    

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19. class Foo {
    private readonly Bar $bar;
    public function __construct(Bar $bar) {
    $this->bar = $bar;
    }
    public function greet() {
    echo "hello " . $this->bar->getName();
    }
    }
    class Bar {
    private readonly string $name;
    public function __construct(string $name) {
    $this->name = $name;
    }
    public function getName(): string
    {
    return $this->name;
    }
    }
    $bar = new Bar("nrs");
    $foo = new Foo($bar);
    $foo->greet();
    

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20. class Foo {
    private readonly Bar $bar;
    public function __construct(Bar $bar) {
    $this->bar = $bar;
    }
    public function greet() {
    echo "hello " . $this->bar->getName();
    }
    }
    class Bar {
    private readonly string $name;
    public function __construct(string $name) {
    $this->name = $name;
    }
    public function getName(): string
    {
    return $this->name;
    }
    }
    $bar = new Bar("nrs");
    $foo = new Foo($bar);
    $foo->greet();
    

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21. class Foo {
    private readonly Bar $bar;
    public function __construct(Bar $bar) {
    $this->bar = $bar;
    }
    public function greet() {
    echo "hello " . $this->bar->getName();
    }
    }
    class Bar {
    private readonly string $name;
    public function __construct(string $name) {
    $this->name = $name;
    }
    public function getName(): string
    {
    return $this->name;
    }
    }
    $bar = new Bar("nrs");
    $foo = new Foo($bar);
    $foo->greet();
    

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22. class Foo {
    private readonly Bar $bar;
    public function __construct(Bar $bar) {
    $this->bar = $bar;
    }
    public function greet() {
    echo "hello " . $this->bar->getName();
    }
    }
    class Bar {
    private readonly string $name;
    public function __construct(string $name) {
    $this->name = $name;
    }
    public function getName(): string
    {
    return $this->name;
    }
    }
    $bar = new Bar("nrs");
    $foo = new Foo($bar);
    $foo->greet();
    

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23. class Foo {
    private readonly Bar $bar;
    public function __construct(Bar $bar) {
    $this->bar = $bar;
    }
    public function greet() {
    echo "hello " . $this->bar->getName();
    }
    }
    class Bar {
    private readonly string $name;
    public function __construct(string $name) {
    $this->name = $name;
    }
    public function getName(): string
    {
    return $this->name;
    }
    }
    

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24. class Foo {
    private readonly Bar $bar;
    public function __construct(Bar $bar) {
    $this->bar = $bar;
    }
    public function greet() {
    echo "hello " . $this->bar->getName();
    }
    }
    class Bar {
    private readonly string $name;
    public function __construct(string $name) {
    $this->name = $name;
    }
    public function getName(): string
    {
    return $this->name;
    }
    }
    

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25. class Foo {
    private readonly Bar $bar;
    public function __construct(Bar $bar) {
    $this->bar = $bar;
    }
    public function greet() {
    echo "hello " . $this->bar->getName();
    }
    }
    class Bar {
    private readonly string $name;
    public function __construct(string $name) {
    $this->name = $name;
    }
    public function getName(): string
    {
    return $this->name;
    }
    }
    

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26. class Foo {
    private readonly Bar $bar;
    public function __construct(Bar $bar) {
    $this->bar = $bar;
    }
    public function greet() {
    echo "hello " . $this->bar->getName();
    }
    }
    class Bar {
    private readonly string $name;
    public function __construct(string $name) {
    $this->name = $name;
    }
    public function getName(): string
    {
    return $this->name;
    }
    }
    

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27. View Slide

28. class UserCreateInteractor implements UserCreateUseCaseInterface
    {
    /**
    * @param UserCreateRequest $request
    * @return UserCreateResponse
    */
    public function handle(UserCreateRequest $request): UserCreateResponse
    {
    $userId = new UserId(uniqid());
    $user = new User($userId, $request->getName());
    DB::table('users')
    ->updateOrInsert(
    ['id' => $user->getId()],
    ['name' => $user->getName()]
    );
    return new UserCreateResponse($userId->getValue());
    }
    }
    use Illuminate¥Support¥Facades¥DB;
    

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29. class UserCreateInteractor implements UserCreateUseCaseInterface
    {
    /**
    * @param UserCreateRequest $request
    * @return UserCreateResponse
    */
    public function handle(UserCreateRequest $request): UserCreateResponse
    {
    $userId = new UserId(uniqid());
    $user = new User($userId, $request->getName());
    DB::table('users')
    ->updateOrInsert(
    ['id' => $user->getId()],
    ['name' => $user->getName()]
    );
    return new UserCreateResponse($userId->getValue());
    }
    }
    use Illuminate¥Support¥Facades¥DB;
    

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30. class UserCreateInteractor implements UserCreateUseCaseInterface
    {
    /**
    * @param UserCreateRequest $request
    * @return UserCreateResponse
    */
    public function handle(UserCreateRequest $request): UserCreateResponse
    {
    $userId = new UserId(uniqid());
    $user = new User($userId, $request->getName());
    DB::table('users')
    ->updateOrInsert(
    ['id' => $user->getId()],
    ['name' => $user->getName()]
    );
    return new UserCreateResponse($userId->getValue());
    }
    }
    use Illuminate¥Support¥Facades¥DB;
    

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31. class UserCreateInteractor implements UserCreateUseCaseInterface
    {
    /**
    * @param UserCreateRequest $request
    * @return UserCreateResponse
    */
    public function handle(UserCreateRequest $request): UserCreateResponse
    {
    $userId = new UserId(uniqid());
    $user = new User($userId, $request->getName());
    DB::table('users')
    ->updateOrInsert(
    ['id' => $user->getId()],
    ['name' => $user->getName()]
    );
    return new UserCreateResponse($userId->getValue());
    }
    }
    use Illuminate¥Support¥Facades¥DB;
    

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32. class UserCreateInteractor implements UserCreateUseCaseInterface
    {
    /**
    * @param UserCreateRequest $request
    * @return UserCreateResponse
    */
    public function handle(UserCreateRequest $request): UserCreateResponse
    {
    $userId = new UserId(uniqid());
    $user = new User($userId, $request->getName());
    DB::table('users')
    ->updateOrInsert(
    ['id' => $user->getId()],
    ['name' => $user->getName()]
    );
    return new UserCreateResponse($userId->getValue());
    }
    }
    use Illuminate¥Support¥Facades¥DB;
    

    View Slide

33. class UserCreateInteractor implements UserCreateUseCaseInterface
    {
    /**
    * @param UserCreateRequest $request
    * @return UserCreateResponse
    */
    public function handle(UserCreateRequest $request): UserCreateResponse
    {
    $userId = new UserId(uniqid());
    $user = new User($userId, $request->getName());
    DB::table('users')
    ->updateOrInsert(
    ['id' => $user->getId()],
    ['name' => $user->getName()]
    );
    return new UserCreateResponse($userId->getValue());
    }
    }
    use Illuminate¥Support¥Facades¥DB;
    

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34. class UserCreateInteractor implements UserCreateUseCaseInterface
    {
    /**
    * @param UserCreateRequest $request
    * @return UserCreateResponse
    */
    public function handle(UserCreateRequest $request): UserCreateResponse
    {
    $userId = new UserId(uniqid());
    $user = new User($userId, $request->getName());
    DB::table('users')
    ->updateOrInsert(
    ['id' => $user->getId()],
    ['name' => $user->getName()]
    );
    return new UserCreateResponse($userId->getValue());
    }
    }
    use Illuminate¥Support¥Facades¥DB;
    

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35. class UserCreateInteractor implements UserCreateUseCaseInterface
    {
    /**
    * @param UserCreateRequest $request
    * @return UserCreateResponse
    */
    public function handle(UserCreateRequest $request): UserCreateResponse
    {
    $userId = new UserId(uniqid());
    $user = new User($userId, $request->getName());
    DB::table('users')
    ->updateOrInsert(
    ['id' => $user->getId()],
    ['name' => $user->getName()]
    );
    return new UserCreateResponse($userId->getValue());
    }
    }
    use Illuminate¥Support¥Facades¥DB;
    

    View Slide

36. class UserCreateInteractor implements UserCreateUseCaseInterface
    {
    /**
    * @param UserCreateRequest $request
    * @return UserCreateResponse
    */
    public function handle(UserCreateRequest $request): UserCreateResponse
    {
    $userId = new UserId(uniqid());
    $user = new User($userId, $request->getName());
    DB::table('users')
    ->updateOrInsert(
    ['id' => $user->getId()],
    ['name' => $user->getName()]
    );
    return new UserCreateResponse($userId->getValue());
    }
    }
    use Illuminate¥Support¥Facades¥DB;
    

    View Slide

37. class UserCreateInteractor implements UserCreateUseCaseInterface
    {
    /**
    * @param UserCreateRequest $request
    * @return UserCreateResponse
    */
    public function handle(UserCreateRequest $request): UserCreateResponse
    {
    $userId = new UserId(uniqid());
    $user = new User($userId, $request->getName());
    DB::table('users')
    ->updateOrInsert(
    ['id' => $user->getId()],
    ['name' => $user->getName()]
    );
    return new UserCreateResponse($userId->getValue());
    }
    }
    use Illuminate¥Support¥Facades¥DB;
    

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38. View Slide

39. View Slide

40. View Slide

41. class UserCreateInteractor implements UserCreateUseCaseInterface
    {
    /**
    * @param UserCreateRequest $request
    * @return UserCreateResponse
    */
    public function handle(UserCreateRequest $request): UserCreateResponse
    {
    $userId = new UserId(uniqid());
    $user = new User($userId, $request->getName());
    DB::table('users')
    ->updateOrInsert(
    ['id' => $user->getId()],
    ['name' => $user->getName()]
    );
    return new UserCreateResponse($userId->getValue());
    }
    }
    use Illuminate¥Support¥Facades¥DB;
    

    View Slide

42. class UserCreateInteractor implements UserCreateUseCaseInterface
    {
    /**
    * @param UserCreateRequest $request
    * @return UserCreateResponse
    */
    public function handle(UserCreateRequest $request): UserCreateResponse
    {
    $userId = new UserId(uniqid());
    $user = new User($userId, $request->getName());
    DB::table('users')
    ->updateOrInsert(
    ['id' => $user->getId()],
    ['name' => $user->getName()]
    );
    return new UserCreateResponse($userId->getValue());
    }
    }
    use Illuminate¥Support¥Facades¥DB;
    

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43. View Slide

44. View Slide

45. View Slide

46. View Slide

47. View Slide

48. View Slide

49. class UserCreateInteractor implements UserCreateUseCaseInterface
    {
    /**
    * @param UserCreateRequest $request
    * @return UserCreateResponse
    */
    public function handle(UserCreateRequest $request): UserCreateResponse
    {
    $userId = new UserId(uniqid());
    $user = new User($userId, $request->getName());
    DB::table('users')
    ->updateOrInsert(
    ['id' => $user->getId()],
    ['name' => $user->getName()]
    );
    return new UserCreateResponse($userId->getValue());
    }
    }
    use Illuminate¥Support¥Facades¥DB;
    

    View Slide

50. class UserCreateInteractor implements UserCreateUseCaseInterface
    {
    /**
    * @param UserCreateRequest $request
    * @return UserCreateResponse
    */
    public function handle(UserCreateRequest $request): UserCreateResponse
    {
    $userId = new UserId(uniqid());
    $user = new User($userId, $request->getName());
    DB::table('users')
    ->updateOrInsert(
    ['id' => $user->getId()],
    ['name' => $user->getName()]
    );
    return new UserCreateResponse($userId->getValue());
    }
    }
    use Illuminate¥Support¥Facades¥DB;
    

    View Slide

51. class UserCreateInteractor implements UserCreateUseCaseInterface
    {
    /**
    * @param UserCreateRequest $request
    * @return UserCreateResponse
    */
    public function handle(UserCreateRequest $request): UserCreateResponse
    {
    $userId = new UserId(uniqid());
    $user = new User($userId, $request->getName());
    DB::table('users')
    ->updateOrInsert(
    ['id' => $user->getId()],
    ['name' => $user->getName()]
    );
    return new UserCreateResponse($userId->getValue());
    }
    }
    use Illuminate¥Support¥Facades¥DB;
    

    View Slide

52. class UserCreateInteractor implements UserCreateUseCaseInterface
    {
    /**
    * @param UserCreateRequest $request
    * @return UserCreateResponse
    */
    public function handle(UserCreateRequest $request): UserCreateResponse
    {
    $userId = new UserId(uniqid());
    $user = new User($userId, $request->getName());
    DB::table('users')
    ->updateOrInsert(
    ['id' => $user->getId()],
    ['name' => $user->getName()]
    );
    return new UserCreateResponse($userId->getValue());
    }
    }
    use Illuminate¥Support¥Facades¥DB;
    

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53. View Slide

54. View Slide

55. View Slide

56. View Slide

57. View Slide

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64. View Slide

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66. View Slide

67. View Slide

68. class QueryBuilderUserRepository
    {
    public function save(User $user)
    {
    DB::table('users')
    ->updateOrInsert(
    ['id' => $user->getId()],
    ['name' => $user->getName()]
    );
    }
    }
    

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69. class UserCreateInteractor implements UserCreateUseCaseInterface
    {
    private $userRepository;
    public function __construct(QueryBuilderUserRepository $userRepository)
    {
    $this->userRepository = $userRepository;
    }
    public function handle(UserCreateRequest $request): UserCreateResponse
    {
    $userId = new UserId(uniqid());
    $user = new User($userId, $request->getName());
    $this->userRepository->save($user);
    return new UserCreateResponse($userId->getValue());
    }
    }
    

    View Slide

70. class UserCreateInteractor implements UserCreateUseCaseInterface
    {
    private $userRepository;
    public function __construct(QueryBuilderUserRepository $userRepository)
    {
    $this->userRepository = $userRepository;
    }
    public function handle(UserCreateRequest $request): UserCreateResponse
    {
    $userId = new UserId(uniqid());
    $user = new User($userId, $request->getName());
    $this->userRepository->save($user);
    return new UserCreateResponse($userId->getValue());
    }
    }
    

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71. View Slide

72. View Slide

73. interface UserRepositoryInterface
    {
    public function save(User $user);
    }
    

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74. View Slide

75. View Slide

76. class QueryBuilderUserRepository
    {
    public function save(User $user)
    {
    DB::table('users')
    ->updateOrInsert(
    ['id' => $user->getId()],
    ['name' => $user->getName()]
    );
    }
    }
    

    View Slide

77. class QueryBuilderUserRepository implements UserRepositoryInterface
    {
    public function save(User $user)
    {
    DB::table('users')
    ->updateOrInsert(
    ['id' => $user->getId()],
    ['name' => $user->getName()]
    );
    }
    }
    

    View Slide

78. View Slide

79. View Slide

80. class UserCreateInteractor implements UserCreateUseCaseInterface
    {
    private $userRepository;
    public function __construct(QueryBuilderUserRepository $userRepository)
    {
    $this->userRepository = $userRepository;
    }
    public function handle(UserCreateRequest $request): UserCreateResponse
    {
    $userId = new UserId(uniqid());
    $user = new User($userId, $request->getName());
    $this->userRepository->save($user);
    return new UserCreateResponse($userId->getValue());
    }
    }
    

    View Slide

81. class UserCreateInteractor implements UserCreateUseCaseInterface
    {
    private $userRepository;
    public function __construct(QueryBuilderUserRepository $userRepository)
    {
    $this->userRepository = $userRepository;
    }
    public function handle(UserCreateRequest $request): UserCreateResponse
    {
    $userId = new UserId(uniqid());
    $user = new User($userId, $request->getName());
    $this->userRepository->save($user);
    return new UserCreateResponse($userId->getValue());
    }
    }
    

    View Slide

82. class UserCreateInteractor implements UserCreateUseCaseInterface
    {
    private $userRepository;
    public function __construct(UserRepositoryInterface $userRepository)
    {
    $this->userRepository = $userRepository;
    }
    public function handle(UserCreateRequest $request): UserCreateResponse
    {
    $userId = new UserId(uniqid());
    $user = new User($userId, $request->getName());
    $this->userRepository->save($user);
    return new UserCreateResponse($userId->getValue());
    }
    }
    

    View Slide

83. class UserCreateInteractor implements UserCreateUseCaseInterface
    {
    private $userRepository;
    public function __construct(UserRepositoryInterface $userRepository)
    {
    $this->userRepository = $userRepository;
    }
    public function handle(UserCreateRequest $request): UserCreateResponse
    {
    $userId = new UserId(uniqid());
    $user = new User($userId, $request->getName());
    $this->userRepository->save($user);
    return new UserCreateResponse($userId->getValue());
    }
    }
    

    View Slide

84. View Slide

85. View Slide

86. View Slide

87. View Slide

88. View Slide

89. View Slide

90. class UserCreateInteractor implements UserCreateUseCaseInterface
    {
    private $userRepository;
    public function __construct(QueryBuilderUserRepository $userRepository)
    {
    $this->userRepository = $userRepository;
    }
    public function handle(UserCreateRequest $request): UserCreateResponse
    {
    $userId = new UserId(uniqid());
    $user = new User($userId, $request->getName());
    $this->userRepository->save($user);
    return new UserCreateResponse($userId->getValue());
    }
    }
    

    View Slide

91. class UserCreateInteractor implements UserCreateUseCaseInterface
    {
    private $userRepository;
    public function __construct(QueryBuilderUserRepository $userRepository)
    {
    $this->userRepository = $userRepository;
    }
    public function handle(UserCreateRequest $request): UserCreateResponse
    {
    $userId = new UserId(uniqid());
    $user = new User($userId, $request->getName());
    $this->userRepository->save($user);
    return new UserCreateResponse($userId->getValue());
    }
    }
    

    View Slide

92. class UserCreateInteractor implements UserCreateUseCaseInterface
    {
    private $userRepository;
    public function __construct(QueryBuilderUserRepository $userRepository)
    {
    $this->userRepository = $userRepository;
    }
    public function handle(UserCreateRequest $request): UserCreateResponse
    {
    $userId = new UserId(uniqid());
    $user = new User($userId, $request->getName());
    $this->userRepository->save($user);
    return new UserCreateResponse($userId->getValue());
    }
    }
    

    View Slide

93. View Slide

94. View Slide

95. View Slide

96. View Slide

97. View Slide

98. class QueryBuilderUserRepository implements UserRepositoryInterface
    {
    public function save(User $user)
    {
    DB::table('users')
    ->updateOrInsert(
    ['id' => $user->getId()],
    ['name' => $user->getName()]
    );
    }
    }
    

    View Slide

99. class QueryBuilderUserRepository implements UserRepositoryInterface
    {
    public function save(User $user)
    {
    DB::table('users')
    ->updateOrInsert(
    ['id' => $user->getId()],
    ['name' => $user->getName()]
    );
    }
    }
    

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100. View Slide

101. View Slide

102. View Slide

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104. View Slide

105. View Slide

106. $repository = new QueryBuilderUserRepository();
     $interactor = new UserCreateInteractor($repository);
     $interactor->handle(new UserCreateRequest("nrs"));
     

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107. $repository = new QueryBuilderUserRepository();
     $interactor = new UserCreateInteractor($repository);
     $interactor->handle(new UserCreateRequest("nrs"));
     

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108. $repository = new AwesomeUserRepository();
     $interactor = new UserCreateInteractor($repository);
     $interactor->handle(new UserCreateRequest("nrs"));
     

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109. $repository = new AwesomeUserRepository();
     $interactor = new UserCreateInteractor($repository);
     $interactor->handle(new UserCreateRequest("nrs"));
     

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110. $repository = new AwesomeUserRepository();
     $interactor = new UserCreateInteractor($repository);
     $interactor->handle(new UserCreateRequest("nrs"));
     

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111. View Slide

112. $this->app->bind(
     UserRepositoryInterface::class,
     QueryBuilderUserRepository::class
     );
     

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113. View Slide

114. View Slide

115. class UserCreateInteractor implements UserCreateUseCaseInterface
     {
     private $userRepository;
     public function __construct(UserRepositoryInterface $userRepository)
     {
     $this->userRepository = $userRepository;
     }
     public function handle(UserCreateRequest $request)
     {
     $userId = new UserId(uniqid());
     $createdUser = new User($userId, $request->getName());
     $this->userRepository->save($createdUser);
     return new UserCreateResponse($userId->getValue());
     }
     }
     

     View Slide

116. class UserCreateInteractor implements UserCreateUseCaseInterface
     {
     private $userRepository;
     public function __construct(UserRepositoryInterface $userRepository)
     {
     $this->userRepository = $userRepository;
     }
     public function handle(UserCreateRequest $request)
     {
     $userId = new UserId(uniqid());
     $createdUser = new User($userId, $request->getName());
     $this->userRepository->save($createdUser);
     return new UserCreateResponse($userId->getValue());
     }
     }
     

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118. class UserController extends BaseController
     {
     public function create(UserCreateUseCaseInterface $interactor, Request $request)
     {
     $name = $request->input('name');
     $request = new UserCreateRequest($name);
     $response = $interactor->handle($request);
     $viewModel = new UserCreateViewModel($response->getCreatedUserId(), $name);
     return view('user.create', compact('viewModel'));
     }
     }
     

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119. class UserController extends BaseController
     {
     public function create(UserCreateUseCaseInterface $interactor, Request $request)
     {
     $name = $request->input('name');
     $request = new UserCreateRequest($name);
     $response = $interactor->handle($request);
     $viewModel = new UserCreateViewModel($response->getCreatedUserId(), $name);
     return view('user.create', compact('viewModel'));
     }
     }
     

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121. @Saga
     class SecureStockIssueSaga {
     @Transient
     @Autowired
     private lateinit var commandGateway: CommandGateway
     private lateinit var sagaState: SecureStockIssuerSagaState
     @StartSaga
     @SagaEventHandler(associationProperty = "secureStockId")
     fun on(event: SecureStockEvents.SecureStockIssued, @MessageIdentifier messageIdentifier: String) {
     sagaState = SecureStockIssuerSagaState(event.secureStockId, secureItemIdToNr = event.itemIdToNr)
     log("[START SAGA] Handling the Secure Stock Issued Event within the Saga ($sagaState).")
     sagaState.secureItemIdToNr.keys.forEach {
     SagaLifecycle.associateWith("itemId", it.asString())
     }
     val commands = event.itemIdToNr.map { (itemId, nr) ->
     ItemAggregateProtocol.SecureItem(itemId, event.secureStockId, nr, messageIdentifier)
     }
     val replies = commands.map { commandGateway.sendAndWait(it) }
     if (replies.any { it is ItemAggregateProtocol.SecureItemFailed }) {
     val secureSucceededList = replies.filterIsInstance()
     compensateSecureStockIssued(secureSucceededList)
     }
     }
     }
     

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122. @Saga
     class SecureStockIssueSaga {
     @Transient
     @Autowired
     private lateinit var commandGateway: CommandGateway
     private lateinit var sagaState: SecureStockIssuerSagaState
     @StartSaga
     @SagaEventHandler(associationProperty = "secureStockId")
     fun on(event: SecureStockEvents.SecureStockIssued, @MessageIdentifier messageIdentifier: String) {
     sagaState = SecureStockIssuerSagaState(event.secureStockId, secureItemIdToNr = event.itemIdToNr)
     log("[START SAGA] Handling the Secure Stock Issued Event within the Saga ($sagaState).")
     sagaState.secureItemIdToNr.keys.forEach {
     SagaLifecycle.associateWith("itemId", it.asString())
     }
     val commands = event.itemIdToNr.map { (itemId, nr) ->
     ItemAggregateProtocol.SecureItem(itemId, event.secureStockId, nr, messageIdentifier)
     }
     val replies = commands.map { commandGateway.sendAndWait(it) }
     if (replies.any { it is ItemAggregateProtocol.SecureItemFailed }) {
     val secureSucceededList = replies.filterIsInstance()
     compensateSecureStockIssued(secureSucceededList)
     }
     }
     }
     

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130. 伝統的なソフトウェア開発手法では高レベルなモジュールが低レベルな
     モジュールに依存する形で作成される傾向がありました。言い換えるな
     ら抽象が詳細に依存するような形で構築されていました。
     抽象が詳細に依存するようになると、低レベルのモジュールにおける方
     針の変更が高レベルのモジュールに波及します。これはおかしな話です。
     重要なドメインのルールが含まれるのはいつだって高レベルなモジュー
     ルです。低レベルなモジュールの変更を理由にして、重要な高レベルの
     モジュールを変更する
     （たとえばデータストアの変更を理由にビジネスロジックを変更する）な
     どということは起きてほしくない事態です。
     主体となるべきは高レベルなモジュール、すなわち抽象です。低レベル
     なモジュールが主体となるべきではありません。
     高レベルなモジュールは低レベルのモジュールを利用するクライアント
     です。クライアントがすべきはどのような処理を呼び出すかの宣言です。
     先述したとおり、インターフェースはそれを利用するクライアントが宣言す
     るものであり、主導権はそのクライアントにあります。インターフェースを宣
     言し、低レベルのモジュールはそのインターフェースに合わせて実装を行
     うことで、より重要な高次元の概念に主導権を握らせることが可能にな
     るのです。
     『ドメイン駆動設計入門 ボトムアップでわかる！ドメイン駆動設計の基本（翔泳社）』 7.3.2
     

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132. OO
     Robert C. Martin
     『CleanArchitecture ( )』
     

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163. OO
     Robert C. Martin
     『CleanArchitecture ( )』
     

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185. OO
     Robert C. Martin
     『CleanArchitecture ( )』
     

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