caSTLe-windsor - 如何配置CaSTLe Windsor以根据提供给Resolve()的参数(“名称”除外)动态选择提供程序

Question

我正在尝试学习如何使用温莎城堡IoC，并且在理解如何配置一些需要动态解析的对象方面遇到一些困难。基本上，我有几个IDataSource的实现，我需要根据如何配置特定的“数据源”来选择要使用的实现。因此，我可能有很多数据源配置为使用3种实现之一。我的期望是，依赖代码将依赖于工厂方法，当提供“数据源ID”以及数据源实现所需的依赖项（IPrincipal）时，该工厂方法将为它们提供正确的IDataSource。

我正在为如何正确编写Windsor的注册代表而苦苦挣扎。以下大致是我所得到的。我正在尝试使用DynamicParameters方法（可能使用的不是正确的方法）来执行找出要使用哪种实现的逻辑，然后调用Resolve提取特定版本。但是我不知道如何返回解析的对象，因为DynamicParameters期望的是ComponentReleasingDelegate，我认为这意味着它应该类似于return k => { k.ReleaseComponent(dataSource); }。但是，如何将已获取的数据源返回给容器以返回给调用者呢？

struct DataSourceInfo {
  string Id;
  string ProviderType;
}

interface ICatalog : IDictionary<string /* Id */, DataSourceInfo> {
  /* ... */
}

class Catalog : ICatalog {
  /* implement dictionary which looks up DataSourceInfo from their string id */
}

interface IDataSource { /* ... */ }

class Source1 : IDataSource {
  Source1(string id, IPrincipal principal) { /* ... */ }
}

class Source2 : IDataSource {
  Source2(string id, IPrincipal principal) { /* ... */ }
}

/* ... */
/* ... inside Windsor configuration section */
container.Register(Component.For<ICatalog>().LifeStyle.Singleton.ImplementedBy<Catalog>());

// Default service provider is a factory method which uses the string (data source id)
// and looks up the DataSourceInfo from the ICatalog.  It then uses info.ProviderType
// to request IoC to resolve that specific implementation and passes in "id" and "principal"
// to be used to resolve the dependencies of the implementation
container.Register(Component.For<IDataSource>().LifeStyle.Transient
  .DynamicParameters((kernel, context, args) => {
      if (args == null || !args.Contains("id") || !(args["id"] is string)) throw ApplicationException("bad args");

      var id = (string)args["id"];
      var catalog = kernel.Resolve<ICatalog>();
      DataSourceInfo info;
      try { info = catalog[id]; } finally { kernel.ReleaseComponent(catalog); }

      // Now resolve the actual IDataSource
      var dataSource = kernel.Resolve<IDataSource>(info.ProviderType, args);

      // How do I return dataSource???
    });

// Now register the actual implementations
container.Register(Component.For<IDataSource>().LifeStyle.Transient.ImplementedBy<Source1>().Named("Source1"));
container.Register(Component.For<IDataSource>().LifeStyle.Transient.ImplementedBy<Source2>().Named("Source2"));

/* ... */
/* some application startup code which configures some data sources */
class AppConfigurer {
  AppConfigurer(ICatalog catalog) {
    catalog["sourceA"] = new DataSourceInfo() { Id = "sourceA", ProviderType = "Source1" }; // data sourceA is provided by Source1 class
    catalog["sourceB"] = new DataSourceInfo() { Id = "sourceB", ProviderType = "Source2" }; // data sourceB is provided by Source2 class
    catalog["sourceC"] = new DataSourceInfo() { Id = "sourceC", ProviderType = "Source2" }; // data sourceC is provided by Source2 class
    catalog["sourceD"] = new DataSourceInfo() { Id = "sourceD", ProviderType = "Source2" }; // data sourceD is provided by Source2 class
    catalog["sourceE"] = new DataSourceInfo() { Id = "sourceE", ProviderType = "Source1" }; // data sourceE is provided by Source1 class        
  }
}

// Here is where I actually want to use IDataSources, and I do not want to know all the business about IDataSourceInfo.  I just know a dataSourceId and an IPrincipal and want to get an IDataSource to work with.
class Dependant {
  Dependant (Func<string, IPrincipal, IDataSource> factory) {
    var sourceA = factory("sourceA", somePrincipal); // sourceA.GetType() == typeof(Source1)
    var sourceB = factory("sourceB", somePrincipal); // sourceB.GetType() == typeof(Source2)
    var sourceC = factory("sourceC", somePrincipal); // sourceC.GetType() == typeof(Source2)
  }
}

编辑：通过从 DynamicParameters切换到 UsingFactoryMethod，我可以做我想要的事情。但是我一直认为这是错误的，因为现在如果我执行 container.ResolveAll()，我真的希望它跳过工厂方法，但是我不知道如何使其执行该操作。

Answer 1

为什么不只创建一个自定义组件类型选择器，然后根据该选择器决定加载哪个组件？

Typed Factory Facility - interface-based factories