在 .NET 中查看 Unity 依赖项配置
本文关键字:依赖 配置 Unity NET | 更新日期: 2023-09-27 18:31:16
我们在Unity Container中有很多注册。 实际上大约有800行长。
由于 Unity 没有验证方法,因此我们在测试应用程序之前引入了单元测试来验证配置,它看起来像下面的东西,运行良好,并且在配置中发现了许多问题:
IUnityContainer container = UnityContainerBuilder.Build();
foreach (ContainerRegistration mapping in container.Registrations)
{
container.Resolve(mapping.RegisteredType, mapping.Name);
}
但是,我们有很多类遵循装饰器模式,其中我们使用命名注册。 然后,这些命名注册用于为其他注册构建 InjectionConstructor,例如:
container.RegisterType<IMyType2, Concrete1MyType2>("Concrete1MyType2", new ContainerControlledLifetimeManager());
container.RegisterType<IMyType2, Concrete2MyType2>("Concrete2MyType2", new ContainerControlledLifetimeManager());
container.RegisterType<IMyType1, Concrete1MyType1>(
"Concrete1MyType1",
new ContainerControlledLifetimeManager(),
new InjectionConstructor(
new ResolvedParameter<IMyType2>("Concrete2MyType2")));
是否可以通过某些代码访问您在 InjectionConstructor 中为注册配置的内容?
这篇文章似乎建议你可以。
给出的示例是:
void DisplayContainerRegistrations(IUnityContainer theContainer)
{
string regName, regType, mapTo, lifetime;
Console.WriteLine("Container has {0} Registrations:",
theContainer.Registrations.Count());
foreach (ContainerRegistration item in theContainer.Registrations)
{
regType = item.RegisteredType.Name;
mapTo = item.MappedToType.Name;
regName = item.Name ?? "[default]";
lifetime = item.LifetimeManagerType.Name;
if (mapTo != regType)
{
mapTo = " -> " + mapTo;
}
else
{
mapTo = string.Empty;
}
lifetime = lifetime.Substring(0, lifetime.Length - "LifetimeManager".Length);
Console.WriteLine("+ {0}{1} '{2}' {3}", regType, mapTo, regName, lifetime);
}
}
好的,在没有获得太多信息之后,我查看了 Unity 的内部结构,因为我看不到任何公开的方法。 我想出了以下内容,它使用反射来访问 Unity 各个部分的私有成员。
这样做的主要原因是将瞬态实例注入单例有点不匹配。 瞬态应该只持续很短的时间,而单例可能会在 DI 容器的整个生命周期中保留。 这里有一些关于简单注射器的好信息。 这是尝试获取注入信息的原因之一,因为 Unity 没有像简单注入器那样的验证。
因此,这是我正在注册的服务接口和类。 有 3 个接口和 3 个具体实现,除了 IService2 有 2 个实现。
public class Service1 : IService1
{
private readonly IService2 _service2;
private readonly IService3 _service3;
public Service1(IService2 service2, IService3 service3)
{
_service2 = service2;
_service3 = service3;
}
public int DoSomethingForService1()
{
return 1;
}
}
public interface IService1
{
int DoSomethingForService1();
}
public class Service2 : IService2
{
public int DoSomethingForService2()
{
return 1;
}
}
public class Service3 : IService3
{
public int DoSomethingForService3()
{
return 1;
}
}
public interface IService3
{
int DoSomethingForService3();
}
public class Service2_1 : IService2
{
public int DoSomethingForService2()
{
return 1;
}
}
public interface IService2
{
int DoSomethingForService2();
}
现在,Unity 容器已构建完毕。 我们倾向于为此使用单独的项目,因为我们不希望所有引用都保存在 UI 中。 我们使用 IService2 的 2 个命名注册。
public static class UnityContainerBuilder
{
public static IUnityContainer BuildDirectInUnity()
{
IUnityContainer container = new UnityContainer();
container.RegisterType<IService2, Service2>("Service2OneAndOnly", new ContainerControlledLifetimeManager());
container.RegisterType<IService2, Service2_1>("Service2_1", new ContainerControlledLifetimeManager());
container.RegisterType<IService3, Service3>(new ContainerControlledLifetimeManager());
container.RegisterType<IService1, Service1>(new ContainerControlledLifetimeManager(),
new InjectionConstructor(
new ResolvedParameter<IService2>("Service2OneAndOnly"),
new ResolvedParameter<IService3>()));
}
}
现在是有趣的部分。 在这里,我们得到了 Unity 配置:
static void Main(string[] args)
{
Console.WriteLine("Building Unity Container...");
var container = (UnityContainer)UnityContainerBuilder.BuildDirectInUnity();
Console.WriteLine("Listing Registrations...");
FieldInfo policiesField = typeof(UnityContainer).GetFields(
BindingFlags.NonPublic |
BindingFlags.Instance).First(f => f.Name == "policies");
FieldInfo parameterValuesField = typeof(SpecifiedConstructorSelectorPolicy).GetFields(
BindingFlags.NonPublic |
BindingFlags.Instance).First(f => f.Name == "parameterValues");
FieldInfo paramNameField = typeof(ResolvedParameter).GetFields(
BindingFlags.NonPublic |
BindingFlags.Instance).First(f => f.Name == "name");
var policies = (PolicyList)policiesField.GetValue(container);
// build up a dictionary for loop below to use to get the lifetime manager
var typeToRegistration = new Dictionary<Tuple<Type, string>, ContainerRegistration>();
foreach (ContainerRegistration registration in container.Registrations)
{
typeToRegistration.Add(new Tuple<Type, string>(registration.RegisteredType, registration.Name), registration);
}
// now output the list
foreach (ContainerRegistration registration in container.Registrations)
{
Console.WriteLine("{0} to {1}, {2}, {3}",
registration.RegisteredType.Name,
registration.MappedToType.Name,
registration.Name ?? "[default]",
registration.LifetimeManagerType.Name);
// need to check for our InjectionConstructor - I need local = false
IConstructorSelectorPolicy constructorPolicy = policies.Get<IConstructorSelectorPolicy>(
new NamedTypeBuildKey(registration.MappedToType, registration.Name), false);
// and I need SpecifiedConstructorSelectorPolicy as we are not using the default constructor
if (constructorPolicy is SpecifiedConstructorSelectorPolicy)
{
var specifiedConstructorPolicy = constructorPolicy as SpecifiedConstructorSelectorPolicy;
// now output the ResolvedParameters for type, name, lifetime manager
var paramValues = (InjectionParameterValue[])parameterValuesField.GetValue(specifiedConstructorPolicy);
foreach (var param in paramValues)
{
if (param is ResolvedParameter)
{
var resolvedParam = param as ResolvedParameter;
var name = (string)paramNameField.GetValue(resolvedParam);
string lifeTimeManagerName =
typeToRegistration[new Tuple<Type, string>(resolvedParam.ParameterType, name)].LifetimeManagerType.Name;
Console.WriteLine("'t{0}, {1}, {2}", param.ParameterTypeName, name ?? "[default]", lifeTimeManagerName);
}
else
{
Console.WriteLine("'t{0}", param.ParameterTypeName);
}
}
}
}
Console.WriteLine("Complete");
Console.ReadLine();
}
这样做的缺点是它纯粹是基于反射的黑客攻击,并且它不支持 InjectionFactory,您可以在其中配置类型的新实例。