Ninject - 请求范围已被处置

Question

我在使用Ninject以及MVC 3应用程序中的扩展EventBroker和DependencyCreation。我已安装并正在使用Ninject.MVC3程序包，因此使用OnePerRequestModule。

我正在试图注入一个服务，名为IParentService到控制器。 IParentService对通过DependencyCreation扩展创建的​​有依赖关系（没有硬引用）。

这两种服务都在本地事件代理实例（本地ParentService）上注册。

我想要IParentService作为每个请求的作用域，我希望将依赖项和事件代理与IParentService同时处置，但是，我得到的是ScopeDisposedException。 我在做什么错？

某些代码：

服务定义：

public interface IParentService 
{ 
} 

public class ParentService : IParentService 
{ 
    [EventPublication("topic://ParentService/MyEvent")] 
    public event EventHandler<EventArgs> MyEvent; 
} 

public class ChildService 
{ 
    [EventSubscription("topic://ParentService/MyEvent", typeof(bbv.Common.EventBroker.Handlers.Publisher))] 
    public void OnMyEvent(object sender, EventArgs eventArgs) 
    {    
    } 
} 

内核登记（NinjectWebCommon）

private static void RegisterServices(IKernel kernel) 
    { 
     kernel.Bind<IParentService>().To<ParentService>() 
      .InRequestScope() 
      .OwnsEventBroker("ParentServiceBroker") 
      .RegisterOnEventBroker("ParentServiceBroker"); 

     kernel.DefineDependency<IParentService, ChildService>(); 
     kernel.Bind<ChildService>().ToSelf() 
      .WhenInjectedInto<ParentService>() 
      .InDependencyCreatorScope() 
      .RegisterOnEventBroker("ParentServiceBroker");    
    } 

堆栈跟踪：

[ScopeDisposedException: The requested scope has already been disposed.] 
    Ninject.Extensions.NamedScope.NamedScopeExtensionMethods.GetScope(IContext context, String scopeParameterName) in c:\Projects\Ninject\ninject.extensions.namedscope\src\Ninject.Extensions.NamedScope\NamedScopeExtensionMethods.cs:118 
    Ninject.Extensions.NamedScope.NamedScopeExtensionMethods.GetScope(IContext context, String scopeParameterName) in c:\Projects\Ninject\ninject.extensions.namedscope\src\Ninject.Extensions.NamedScope\NamedScopeExtensionMethods.cs:126 
    Ninject.Extensions.NamedScope.<>c__DisplayClass1`1.<InNamedScope>b__0(IContext context) in c:\Projects\Ninject\ninject.extensions.namedscope\src\Ninject.Extensions.NamedScope\NamedScopeExtensionMethods.cs:40 
    Ninject.Planning.Bindings.BindingConfiguration.GetScope(IContext context) in c:\Projects\Ninject\ninject\src\Ninject\Planning\Bindings\BindingConfiguration.cs:119 
    Ninject.Planning.Bindings.Binding.GetScope(IContext context) in c:\Projects\Ninject\ninject\src\Ninject\Planning\Bindings\Binding.cs:224 
    Ninject.Activation.Context.GetScope() in c:\Projects\Ninject\ninject\src\Ninject\Activation\Context.cs:123 
    Ninject.Activation.Caching.Cache.TryGet(IContext context) in c:\Projects\Ninject\ninject\src\Ninject\Activation\Caching\Cache.cs:110 
    Ninject.Activation.Context.Resolve() in c:\Projects\Ninject\ninject\src\Ninject\Activation\Context.cs:150 
    Ninject.<>c__DisplayClass10.<Resolve>b__c(IBinding binding) in c:\Projects\Ninject\ninject\src\Ninject\KernelBase.cs:386 
    System.Linq.WhereSelectEnumerableIterator`2.MoveNext() +145 
    System.Linq.<CastIterator>d__b1`1.MoveNext() +85 
    System.Linq.Enumerable.Single(IEnumerable`1 source) +191 
    Ninject.ResolutionExtensions.Get(IResolutionRoot root, String name, IParameter[] parameters) in c:\Projects\Ninject\ninject\src\Ninject\Syntax\ResolutionExtensions.cs:50 
    Ninject.Extensions.ContextPreservation.ContextPreservationExtensionMethods.ContextPreservingGet(IContext context, String name, IParameter[] parameters) in c:\Projects\Ninject\ninject.extensions.contextpreservation\src\Ninject.Extensions.ContextPreservation\ContextPreservationExtensionMethods.cs:56 
    Ninject.Extensions.bbvEventBroker.<>c__DisplayClass2`1.<RegisterOnEventBroker>b__0(IContext ctx, T instance) in c:\Projects\Ninject\ninject.extensions.bbveventbroker\src\Ninject.Extensions.bbvEventBroker\EventBrokerExtensionMethods.cs:45 
    Ninject.Planning.Bindings.<>c__DisplayClass29`1.<OnDeactivation>b__28(IContext context, Object instance) in c:\Projects\Ninject\ninject\src\Ninject\Planning\Bindings\BindingConfigurationBuilder.cs:513 
    Ninject.Activation.Strategies.<>c__DisplayClass4.<Deactivate>b__3(Action`2 action) in c:\Projects\Ninject\ninject\src\Ninject\Activation\Strategies\BindingActionStrategy.cs:42 
    Ninject.Infrastructure.Language.ExtensionsForIEnumerableOfT.Map(IEnumerable`1 series, Action`1 action) in c:\Projects\Ninject\ninject\src\Ninject\Infrastructure\Language\ExtensionsForIEnumerableOfT.cs:32 
    Ninject.Activation.Strategies.BindingActionStrategy.Deactivate(IContext context, InstanceReference reference) in c:\Projects\Ninject\ninject\src\Ninject\Activation\Strategies\BindingActionStrategy.cs:42 
    Ninject.Activation.<>c__DisplayClass6.<Deactivate>b__4(IActivationStrategy s) in c:\Projects\Ninject\ninject\src\Ninject\Activation\Pipeline.cs:72 
    Ninject.Infrastructure.Language.ExtensionsForIEnumerableOfT.Map(IEnumerable`1 series, Action`1 action) in c:\Projects\Ninject\ninject\src\Ninject\Infrastructure\Language\ExtensionsForIEnumerableOfT.cs:32 
    Ninject.Activation.Pipeline.Deactivate(IContext context, InstanceReference reference) in c:\Projects\Ninject\ninject\src\Ninject\Activation\Pipeline.cs:72 
    Ninject.Activation.Caching.Cache.Forget(CacheEntry entry) in c:\Projects\Ninject\ninject\src\Ninject\Activation\Caching\Cache.cs:253 
    Ninject.Activation.Caching.Cache.Forget(IEnumerable`1 cacheEntries) in c:\Projects\Ninject\ninject\src\Ninject\Activation\Caching\Cache.cs:242 
    Ninject.Activation.Caching.Cache.Clear(Object scope) in c:\Projects\Ninject\ninject\src\Ninject\Activation\Caching\Cache.cs:197 
    Ninject.Web.Common.<>c__DisplayClass2.<DeactivateInstancesForCurrentHttpRequest>b__1(IKernel kernel) in c:\Projects\Ninject\Ninject.Web.Common\src\Ninject.Web.Common\OnePerRequestHttpModule.cs:74 
    Ninject.GlobalKernelRegistration.MapKernels(Action`1 action) in c:\Projects\Ninject\ninject\src\Ninject\GlobalKernelRegistration.cs:75 
    Ninject.Web.Common.OnePerRequestHttpModule.DeactivateInstancesForCurrentHttpRequest() in c:\Projects\Ninject\Ninject.Web.Common\src\Ninject.Web.Common\OnePerRequestHttpModule.cs:74 
    Ninject.Web.Common.OnePerRequestHttpModule.<Init>b__0(Object o, EventArgs e) in c:\Projects\Ninject\Ninject.Web.Common\src\Ninject.Web.Common\OnePerRequestHttpModule.cs:56 
    System.Web.SyncEventExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +136 
    System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +69 

编辑 - 更多详情

错误是在调用设置为RegisterOnEventBroker，其中代码试图注销的事件代理注册的任何对象停用委托中抛出。它失败了，因为事件代理范围已被处置，可能是因为父服务已被处置。据我所知，Ninject只会调用OnDeactivation委托对象的生存时间以外的Transient作用域，所以当父服务注册在RequestScope混淆我时，为什么这不起作用。由于此问题，我正在经历内存泄漏，所以父服务的暂态范围不足。

我开始怀疑这是否是EventBroker扩展中的错误。

Answer 1

您必须先将IParentService绑定到ParentService，然后使用具体类型为kernel.Bind<ParentService>().ToSelf()的自绑定来定义对象范围和事件代理。

private static void RegisterServices(IKernel kernel) 
    { 
     kernel.Bind<IParentService>().To<ParentService>(); 


     kernel.Bind<ParentService>().ToSelf() 
     .InRequestScope() 
     .OwnsEventBroker("ParentServiceBroker") 
     .RegisterOnEventBroker("ParentServiceBroker"); 

     kernel.DefineDependency<IParentService, ChildService>(); 
     kernel.Bind<ChildService>().ToSelf() 
      .WhenInjectedInto<ParentService>() 
      .InDependencyCreatorScope() 
      .RegisterOnEventBroker("ParentServiceBroker"); 
    }  

编辑： 如果你正在解决的类型是具体类型（如上面ParentService），Ninject会自动创建通过一个称为隐自我约束机制默认关联。 像这样：

kernel.Bind<ParentService>().ToSelf(); 

在另一方面隐自我绑定在默认的对象范围是Transient产生。这就是为什么你的代码不能在Request范围内运行。

有关详细信息，请参阅here

编辑2：

有一个在bbvEventBroker延伸在Request范围造成EventBroker被哪些寄存器上EventBroker对象的处理之前设置的错误。因此在该对象的OnDeactivation方法中没有可以调用Unregister的EventBroker，并且抛出了ScopeDisposedException。

public static IBindingOnSyntax<T> OwnsEventBroker<T>(this IBindingOnSyntax<T> syntax, string eventBrokerName) 
    { 
     string namedScopeName = "EventBrokerScope" + eventBrokerName; 
     syntax.DefinesNamedScope(namedScopeName); 
     syntax.Kernel.Bind<IEventBroker>().To<EventBroker>().InNamedScope(namedScopeName).Named(eventBrokerName); 
     syntax.Kernel.Bind<IEventBroker>().ToMethod(ctx => ctx.ContextPreservingGet<IEventBroker>(eventBrokerName)).WhenTargetNamed(eventBrokerName); 
     return syntax; 
    } 

可以在OwnsEventBroker方法参见NamedScope其​​中执行它的对象（ParentService）之前处理所述对象（ParentService）的范围限定。

另一方面，在对象（ParentService）的OnDeactivation中，需要先前配置的EventBroker。

public static IBindingOnSyntax<T> RegisterOnEventBroker<T>(
     this IBindingOnSyntax<T> syntax, string eventBrokerName) 
    { 
     return 
      syntax.OnActivation((ctx, instance) => ctx.ContextPreservingGet<IEventBroker>(eventBrokerName).Register(instance)) 
        .OnDeactivation((ctx, instance) => ctx.ContextPreservingGet<IEventBroker>(eventBrokerName).Unregister(instance)); 
    } 

EventBrokerExtensionMethods.cs

溶液与NamedScope创建对象树。在Request范围内定义父项，同时为子项（发布者/订阅者）定义NamedScope并拥有事件代理（OwnsEventBroker）。然后定义一个发布者（ChildService1）和一个订阅者（ChildService2）在父指定的范围内。通过这种方式，您可以确保活动经纪人的所有者在他们的孩子后被处置。

Answer 2

Ninject内核当前取消激活对象本身之前处于对象范围内的对象。

更改顺序似乎解决了这个问题。虽然在推动这个变化之前，我必须检查这可能对其他情况有什么副作用。