c# - 组件和服务依赖项之间有什么区别？

Question

我将在这个问题的开头声明:我知道以下是糟糕的设计，但重构目前不是一个选项，理想情况下应该使用拦截器来完成。

我正在努力将 caSTLe 从 1.6(我认为)升级到 3.3，不幸的是，这涉及一些语法更改，我现在已经编译了所有内容，但我围绕服务容器的一些测试无法正常工作。

我有一个存储库，它有多个实现来提供不同的功能，该存储库只用于内联的所有不同实现，这里是代码的基础:

温莎城堡注册:

RepositoryRegistration<IAccountRepository, AccountRepositoryFeedEntryDecorator>()
    .DependsOn(Dependency.OnComponent("decoratedRepository", typeof(AccountRepositoryAuthorizationDecorator))),
RepositoryRegistration<AccountRepositoryAuthorizationDecorator>()
    .DependsOn(Dependency.OnComponent("decoratedRepository", typeof(AccountRepositoryMaskingDecorator))),
RepositoryRegistration<AccountRepositoryMaskingDecorator>()
    .DependsOn(Dependency.OnComponent("decoratedRepository", typeof(AccountRepository))),
RepositoryRegistration<AccountRepository>());

RepositoryRegistration 方法:

private static ComponentRegistration<TRepository> RepositoryRegistration<TRepository, TConcreteRepository>()
    where TConcreteRepository : TRepository where TRepository : class
{
    return Component
               .For<TRepository>()
               .ImplementedBy<TConcreteRepository>()                    
               .Named(typeof(TConcreteRepository).Name);
}

基础接口(interface):

public interface IAccountRepository
{
    string Create(Account account);
    void Update(Account account);
    Account Get(string accountId);
}

实现:

public class AccountRepositoryFeedEntryDecorator : IAccountRepository
{
    private readonly IAccountRepository decoratedRepository;
    public AccountRepositoryFeedEntryDecorator(
        IAccountRepository decoratedRepository)
    {
        this.decoratedRepository = decoratedRepository;
    }

    string Create(Account account)
    {
        //Add Entry To Feed
        return decoratedRepository.Create(account);
    };

    void Update(Account account)
    {
        //Add Entry To Feed
        return decoratedRepository.Udpate(account);
    }
    Account Get(string accountId);
    {
        //Add Entry To Feed
        return decoratedRepository.Get(accountId);
    }
}

public class AccountRepositoryAuthorizationDecorator : IAccountRepository
{
    private readonly IAccountRepository decoratedRepository;
    public AccountRepositoryAuthorizationDecorator(
        IAccountRepository decoratedRepository)
    {
        this.decoratedRepository = decoratedRepository;
    }

    string Create(Account account)
    {
        //Ensure User Is Authorized
        return decoratedRepository.Create(account);
    };

    void Update(Account account)
    {
        //Ensure User Is Authorized
        return decoratedRepository.Udpate(account);
    }
    Account Get(string accountId);
    {
        //Ensure User Is Authorized
        return decoratedRepository.Get(accountId);
    }
}

public class AccountRepositoryMaskingDecorator : IAccountRepository
{
    private readonly IAccountRepository decoratedRepository;
    public AccountRepositoryMaskingDecorator(
        IAccountRepository decoratedRepository)
    {
        this.decoratedRepository = decoratedRepository;
    }

    string Create(Account account)
    {
        //Mask Sensitive Information
        return decoratedRepository.Create(account);
    };

    void Update(Account account)
    {
        //Mask Sensitive Information
        return decoratedRepository.Udpate(account);
    }
    Account Get(string accountId);
    {
        //Mask Sensitive Information
        return decoratedRepository.Get(accountId);
    }
}

public class AccountRepository : IAccountRepository
{       
    string Create(Account account)
    {
        //Create account and return details
    };

    void Update(Account account)
    {
        //Update account and return details
    }
    Account Get(string accountId);
    {
        //Return Account
    }
}

最后是我在测试中遇到的错误:

Castle.MicroKernel.Handlers.HandlerException : Can't create component 'AccountRepositoryFeedEntryDecorator' as it has dependencies to be satisfied.

'AccountRepositoryFeedEntryDecorator' is waiting for the following dependencies: - Component 'Shaw.Services.CustomerManagement.Host.Repositories.Sql.Decorators.AccountRepositoryAuthorizationDecorator' (via override) which was registered but is also waiting for dependencies.

'Shaw.Services.CustomerManagement.Host.Repositories.Sql.Decorators.AccountRepositoryAuthorizationDecorator' is waiting for the following dependencies: - Service 'AccountRepositoryFeedEntryDecorator' which was registered but is also waiting for dependencies.

乍一看似乎发生了某种循环依赖，但我真的看不出是怎么回事。

所以问题分为两部分，错误消息中的组件和服务依赖规范之间的区别是什么，关于哪里出了问题的任何猜测。

如果这里重要的是升级前的原始注册:

RepositoryRegistration<IAccountRepository, AccountRepositoryFeedEntryDecorator>()
    .ServiceOverrides(new { decoratedRepository = typeof(AccountRepositoryAuthorizationDecorator).Name }),
RepositoryRegistration<AccountRepositoryAuthorizationDecorator>()
    .ServiceOverrides(new { decoratedRepository = typeof(AccountRepositoryMaskingDecorator).Name }),
RepositoryRegistration<AccountRepositoryMaskingDecorator>()
    .ServiceOverrides(new { decoratedRepository = typeof(AccountRepository).Name }),
RepositoryRegistration<AccountRepository>()

Answer 1

装饰器注册按注册顺序进行，您不需要指定依赖项，因此这会像您期望的那样工作:

container.Register(
    RepositoryRegistration<IAccountRepository, AccountRepositoryFeedEntryDecorator>(),
    RepositoryRegistration<IAccountRepository, AccountRepositoryAuthorizationDecorator>(),
    RepositoryRegistration<IAccountRepository, AccountRepositoryMaskingDecorator>(),
    RepositoryRegistration<IAccountRepository, AccountRepository>()
);

解析 IAccountRepository 的实例将产生一个 AccountRepositoryFeedEntryDecorator，它装饰了一个 AccountRepositoryAuthorizationDecorator 等

---

关于您的问题，this page很好地解释了服务、组件和依赖项之间的差异，因为这些术语在库中使用。本质上:

• 服务 是一些功能契约，通常是接口(interface)或委托(delegate)。它是抽象的。
• 组件 是服务的实现，通常是类。它是具体的。
• 依赖性是组件使用的服务。

在您的错误消息中，第一位是:

Castle.MicroKernel.Handlers.HandlerException : Can't create component 'AccountRepositoryFeedEntryDecorator' as it has dependencies to be satisfied.

好的，所以无法创建组件/类，因为无法满足其依赖性。它的依赖项是构造函数中的 IAccountRepository decoratedRepository 参数。

'AccountRepositoryFeedEntryDecorator' is waiting for the following dependencies: - Component 'AccountRepositoryAuthorizationDecorator' (via override) which was registered but is also waiting for dependencies.

我们仍在谈论同一个组件/类，它说它试图使用组件/类 AccountRepositoryAuthorizationDecorator 来实现其依赖性，但该类也有依赖性。

'AccountRepositoryAuthorizationDecorator' is waiting for the following dependencies: - Service 'AccountRepositoryFeedEntryDecorator' which was registered but is also waiting for dependencies.

我们已经回到了第一类，所以存在循环依赖。这是因为 RepositoryRegistration 中设置的名称与将类型传递给 Dependency.OnComponent 时计算的名称之间存在脱节。对于前者，您正在使用 Type.Name(即“AccountRepositoryFeedEntryDecorator”)，对于后者，Windsor 在幕后使用 Type.FullName(即“您的.Assembly.Name，AccountRepositoryFeedEntryDecorator”)。

由于命名不匹配，当 Windsor 尝试实现您指定的依赖项时，它将错过对其的注册，因为它具有不同的名称。结果，它在没有信息的情况下尽力而为，并且(我假设)找到了第一个 IAccountRepository——这不是组件本身——它可以作为依赖项插入。这种依赖性再次发生，这是我们开始使用的第一个组件，提供循环依赖性。

您可以通过删除注册的 Named 部分或将 typeof(AccountRepositoryAuthorizationDecorator).Name 传递给 Dependency.OnComponent 来解决这个问题> 而不是类型本身。