Dependency injection IDependencyResolver实现的Web Api启动异常
我正在开发一个Web Api,我决定使用自定义DependencyResolver。我指的是这篇文章。到目前为止,在向控制器注入依赖项方面,一切都运行良好。Owin启动类中的配置代码片段Dependency injection IDependencyResolver实现的Web Api启动异常,dependency-injection,unity-container,asp.net-web-api,dependency-resolver,Dependency Injection,Unity Container,Asp.net Web Api,Dependency Resolver,我正在开发一个Web Api,我决定使用自定义DependencyResolver。我指的是这篇文章。到目前为止,在向控制器注入依赖项方面,一切都运行良好。Owin启动类中的配置代码片段 private void RegisterIoC(HttpConfiguration config) { _unityContainer = new UnityContainer(); _unityContainer.RegisterType<IAccountService, Accoun
private void RegisterIoC(HttpConfiguration config)
{
_unityContainer = new UnityContainer();
_unityContainer.RegisterType<IAccountService, AccountService>();
.........
.........
config.DependencyResolver = new UnityResolver(_unityContainer);
}
上述相同的引发以下类型的异常
System.Web.Http.Hosting.IHostBufferPolicySelector
System.Web.Http.Tracing.ITraceWriter
System.Web.Http.Metadata.ModelMetadataProvider
System.Web.Http.Tracing.ITraceManager
System.Web.Http.Dispatcher.IHttpControllerSelector
System.Web.Http.Dispatcher.IAssembliesResolver
System.Web.Http.Dispatcher.IHttpControllerTypeResolver
System.Web.Http.Controllers.IHttpActionSelector
System.Web.Http.Controllers.IActionValueBinder
System.Web.Http.Validation.IBodyModelValidator
System.Net.Http.Formatting.IContentNegotiator
我知道抛出这些ResolutionFailedException是因为我在unity配置中没有为上述类型提供映射
现在我的问题是:-,如果我实现自定义unity DependencyResolver,我需要定义上述类型的映射,如果需要定义它们对应的默认实现类型,或者是否有其他方法实现DependencyResolver。我真的很担心,即使应用程序现在运行良好,未能解决上述类型可能会导致严重的问题以后请帮助
最后添加一项:-
对于以下类型,当我向my web api请求任何操作时,会引发相同的ResolutionFailedException
System.Web.Http.Dispatcher.IHttpControllerActivator
System.Web.Http.Validation.IModelValidatorCache
System.Web.Http.Controllers.IHttpActionInvoker
通常情况下,你不需要团结一致。 我将此实现用于unity的IDependencyResolver,除了我的接口/服务之外,我不必注册或映射
public class UnityDependencyInjectionResolver : Disposable, IDependencyResolver
{
protected IUnityContainer Container;
public UnityDependencyInjectionResolver(IUnityContainer container)
{
if (container == null)
{
throw new ArgumentNullException("container");
}
Container = container;
}
public object GetService(Type serviceType)
{
try
{
return Container.Resolve(serviceType);
}
catch (ResolutionFailedException)
{
return null;
}
}
public T GetService<T>()
{
try
{
var serviceType = typeof(T);
return (T)Container.Resolve(serviceType);
}
catch (ResolutionFailedException)
{
return default(T);
}
}
public T GetService<T>(string name)
{
try
{
var serviceType = typeof (T);
return (T) Container.Resolve(serviceType, name);
}
catch (ResolutionFailedException)
{
return default(T);
}
}
public IEnumerable<object> GetServices(Type serviceType)
{
try
{
return Container.ResolveAll(serviceType);
}
catch (ResolutionFailedException)
{
return new List<object>();
}
}
public IDependencyScope BeginScope()
{
var child = Container.CreateChildContainer();
return new UnityDependencyInjectionResolver(child);
}
protected override void DisposeManagedResources()
{
if (Container == null)
{
return;
}
Container.Dispose();
Container = null;
}
}
公共类UnityDependencyInjectionResolver:一次性的IDependencyResolver
{
受保护的IUnity容器;
公共UnityDependencyInjectionResolver(IUnityContainer容器)
{
if(容器==null)
{
抛出新的ArgumentNullException(“容器”);
}
容器=容器;
}
公共对象GetService(类型serviceType)
{
尝试
{
返回容器解析(serviceType);
}
捕获(解决失败异常)
{
返回null;
}
}
公共服务
{
尝试
{
var serviceType=typeof(T);
返回(T)容器解析(serviceType);
}
捕获(解决失败异常)
{
返回默认值(T);
}
}
公共GetT服务(字符串名称)
{
尝试
{
var serviceType=typeof(T);
return(T)Container.Resolve(serviceType,name);
}
捕获(解决失败异常)
{
返回默认值(T);
}
}
公共IEnumerable GetServices(类型serviceType)
{
尝试
{
返回容器.ResolveAll(serviceType);
}
捕获(解决失败异常)
{
返回新列表();
}
}
公共IDependencyScope BeginScope()
{
var child=Container.CreateChildContainer();
返回新的UnitedPendencyInjectionResolver(子级);
}
受保护的覆盖void DisposeManagedResources()
{
if(容器==null)
{
返回;
}
Container.Dispose();
Container=null;
}
}
其中Disposable只是实现IDisTable的基类
希望能有所帮助。我使用Unity与WebApi和OWIN/Katana遇到了同样的问题 我的解决方案是使用Unity.WebApi Nuget包中定义的UnityDependencyResolver,而不是我自己的自定义实现(如上面的@Omar Alani) 请注意,该包将尝试在App_Start(我自己使用的文件名)中添加一个名为UnityConfig.cs的文件 在该UnityConfig.cs文件中,包将添加代码,以便根据
GlobalConfiguration.Configuration.DependencyResolver
注册容器,而这不是我们想要的OWIN
因此,与其使用:
GlobalConfiguration.Configuration.DependencyResolver = new UnityDependencyResolver(container);
更改为使用:
config.DependencyResolver = new UnityDependencyResolver(container);
完整性:
我的UnityConfig.cs
public static class UnityConfig
{
public static void Register(HttpConfiguration config)
{
var container = new UnityContainer();
// Your mappings here
config.DependencyResolver = new UnityDependencyResolver(container);
}
}
我的Startup.cs
[assembly: OwinStartup(typeof(UnityTest.BusinessLayer.Api.ApiStartup))]
namespace UnityTest.BusinessLayer.Api
{
public partial class ApiStartup
{
public void Configuration(IAppBuilder app)
{
app.UseCors(Microsoft.Owin.Cors.CorsOptions.AllowAll);
HttpConfiguration httpConfig = new HttpConfiguration();
UnityConfig.Register(httpConfig);
ConfigureAuth(app); //In App_Start ->Startup.Auth
WebApiConfig.Register(httpConfig);
app.UseWebApi(httpConfig);
}
}
}
Unity.WebAPI
的实现与问题中提到的没有太大区别。我喜欢OP提到的版本,因为它只忽略resultationfailedexception
,并让其余部分向上传播Unity.WebAPI
抑制所有异常。我要做的是忽略我们知道安全的错误,并记录(或重发)其他错误
我已删除dependencyResolver,此问题已解决
public static class UnityConfig
{
public static void Register(HttpConfiguration config)
{
var container = new UnityContainer();
// Your mappings here
config.DependencyResolver = null;
}
}
如果上述任何一种解决方案仍然不适用于人们,下面是我如何解决的
在花了一天的时间追查这个错误之后,结果发现这是某种VS缓存问题。出于绝望,我删除了所有.suo文件并强制获取最新版本,这似乎解决了问题。这是很久以前提出的问题,但我遇到了一个此处未提及的解决方案,因此可能仍有人感兴趣
在我的例子中,这些异常已经被Unity(或其他什么)在内部捕获,但我在VisualStudio中的异常设置使它们仍然显示出来。我只需取消选中“显示此异常类型时中断”复选框,应用程序就可以正常运行。由于这似乎仍有争议,下面是我的代码版本
/// <summary>
/// Specifies the Unity configuration for the main container.
/// </summary>
public class UnityConfig
{
private static Lazy<IUnityContainer> container = new Lazy<IUnityContainer>(() =>
{
var container = new UnityContainer();
RegisterTypes(container);
return container;
});
/// <summary>
/// Gets the configured Unity container.
/// </summary>
public static IUnityContainer GetConfiguredContainer()
{
return container.Value;
}
public static void RegisterTypes(IUnityContainer container)
{
// Keeping this separate allows easier unit testing
// Your type mappings here
}
}
最后,bits是在Owin中间件中使用作用域容器以及直接WebAPI的扩展
public static class AppBuilderExtensions
{
public static IAppBuilder UseDependencyResolverScope(this IAppBuilder app, IDependencyResolver resolver)
{
return app.Use<DependencyResolverScopeMiddleware>(resolver);
}
}
/// <summary>
/// Wraps middleware in a <see cref="IDependencyResolver"/> scope.
/// </summary>
public class DependencyResolverScopeMiddleware : OwinMiddleware
{
private readonly IDependencyResolver resolver;
public DependencyResolverScopeMiddleware(OwinMiddleware next, IDependencyResolver resolver) : base(next)
{
this.resolver = resolver;
}
public override async Task Invoke(IOwinContext context)
{
using (var scope = resolver.BeginScope())
{
context.SetDependencyScope(scope);
await Next.Invoke(context);
}
}
}
公共静态类AppBuilderExtensions
{
公共静态IAppBuilder UseDependencyResolverScope(此IAppBuilder应用程序,IDependencyResolver解析器)
{
返回应用程序使用(解析器);
}
}
///
///将中间件包装到范围中。
///
公共类依赖解析镜中间件:OwinMiddleware
{
专用只读IDependencyResolver解析器;
公共依赖解析镜中间件(OwinMiddleware next,IDependencyResolver resolver):基础(next)
{
this.resolver=解析器;
}
公共重写异步任务调用(IOwinContext上下文)
{
使用(var scope=resolver.BeginScope())
{
context.SetDependencyScope(范围);
等待下一步。调用(上下文);
}
}
}
理由
public static class UnityConfig
{
public static void Register(HttpConfiguration config)
{
var container = new UnityContainer();
// Your mappings here
config.DependencyResolver = null;
}
}
/// <summary>
/// Specifies the Unity configuration for the main container.
/// </summary>
public class UnityConfig
{
private static Lazy<IUnityContainer> container = new Lazy<IUnityContainer>(() =>
{
var container = new UnityContainer();
RegisterTypes(container);
return container;
});
/// <summary>
/// Gets the configured Unity container.
/// </summary>
public static IUnityContainer GetConfiguredContainer()
{
return container.Value;
}
public static void RegisterTypes(IUnityContainer container)
{
// Keeping this separate allows easier unit testing
// Your type mappings here
}
}
[assembly: OwinStartup(typeof(UnityTest.BusinessLayer.Api.ApiStartup))]
namespace UnityTest.BusinessLayer.Api
{
public static HttpConfiguration Config { get; private set; }
public partial class ApiStartup
{
public void Configuration(IAppBuilder app)
{
// IoC
var container = UnityConfig.GetConfiguredContainer();
var resolver = new UnityHierarchicalDependencyResolver(container); // Gets us scoped resolution
app.UseDependencyResolverScope(resolver); // And for the OWIN
app.UseCors(Microsoft.Owin.Cors.CorsOptions.AllowAll);
// NB Must be before WebApiConfig.Register
ConfigureAuth(app); //In App_Start ->Startup.Auth
// See http://stackoverflow.com/questions/33402654/web-api-with-owin-throws-objectdisposedexception-for-httpmessageinvoker
// and http://aspnetwebstack.codeplex.com/workitem/2091
#if SELFHOST
// WebAPI configuration
Config = new HttpConfiguration
{
DependencyResolver = resolver
};
WebApiConfig.Register(Config);
app.UseWebApi(Config);
#else
GlobalConfiguration.Configuration.DependencyResolver = resolver;
// http://stackoverflow.com/questions/19907226/asp-net-webapi-2-attribute-routing-not-working
// Needs to be before RouteConfig.RegisterRoutes(RouteTable.Routes);
GlobalConfiguration.Configure(WebApiConfig.Register);
Config = GlobalConfiguration.Configuration;
#endif
// Now do MVC configuration if appropriate
}
}
}
public static class AppBuilderExtensions
{
public static IAppBuilder UseDependencyResolverScope(this IAppBuilder app, IDependencyResolver resolver)
{
return app.Use<DependencyResolverScopeMiddleware>(resolver);
}
}
/// <summary>
/// Wraps middleware in a <see cref="IDependencyResolver"/> scope.
/// </summary>
public class DependencyResolverScopeMiddleware : OwinMiddleware
{
private readonly IDependencyResolver resolver;
public DependencyResolverScopeMiddleware(OwinMiddleware next, IDependencyResolver resolver) : base(next)
{
this.resolver = resolver;
}
public override async Task Invoke(IOwinContext context)
{
using (var scope = resolver.BeginScope())
{
context.SetDependencyScope(scope);
await Next.Invoke(context);
}
}
}