Autofac - 请求的服务 (lSomeDbContext) 尚未注册

Question

我一直在做一个项目，使用OnionWebApiStarterKit作为学习CQRS方法的基础。

虽然上面 OnionWebApiStarterKit 项目中的 WebApi StudentsController示例只注入了 IMediator，但我决定在 AccountController 构造函数中注入我的自定义IApplicationUserManager会更容易，因为它严重依赖于用户操作：

public AccountsController(
    IMediator mediator, 
    IApplicationUserManager userManager)
{
    // and so on...    
}

但是，这会产生以下错误：

“请求的服务 'OnionWebApiStarterKit.Data.ISchoolDbContext' 尚未注册。”

完整的堆栈跟踪如下：

"message": "An error has occurred.",
  "exceptionMessage": "An error occurred when trying to create a controller of type 'AccountsController'. Make sure that the controller has a parameterless public constructor.",
  "exceptionType": "System.InvalidOperationException",
  "stackTrace": "   at System.Web.Http.Dispatcher.DefaultHttpControllerActivator.Create(HttpRequestMessage request, HttpControllerDescriptor controllerDescriptor, Type controllerType)\r\n   at System.Web.Http.Tracing.Tracers.HttpControllerActivatorTracer.<>c__DisplayClass2.<System.Web.Http.Dispatcher.IHttpControllerActivator.Create>b__0()\r\n   at System.Web.Http.Tracing.ITraceWriterExtensions.TraceBeginEnd(ITraceWriter traceWriter, HttpRequestMessage request, String category, TraceLevel level, String operatorName, String operationName, Action`1 beginTrace, Action execute, Action`1 endTrace, Action`1 errorTrace)\r\n   at System.Web.Http.Tracing.Tracers.HttpControllerActivatorTracer.System.Web.Http.Dispatcher.IHttpControllerActivator.Create(HttpRequestMessage request, HttpControllerDescriptor controllerDescriptor, Type controllerType)\r\n   at System.Web.Http.Controllers.HttpControllerDescriptor.CreateController(HttpRequestMessage request)\r\n   at System.Web.Http.Tracing.Tracers.HttpControllerDescriptorTracer.<>c__DisplayClass2.<CreateController>b__0()\r\n   at System.Web.Http.Tracing.ITraceWriterExtensions.TraceBeginEnd(ITraceWriter traceWriter, HttpRequestMessage request, String category, TraceLevel level, String operatorName, String operationName, Action`1 beginTrace, Action execute, Action`1 endTrace, Action`1 errorTrace)\r\n   at System.Web.Http.Tracing.Tracers.HttpControllerDescriptorTracer.CreateController(HttpRequestMessage request)\r\n   at System.Web.Http.Dispatcher.HttpControllerDispatcher.<SendAsync>d__1.MoveNext()",
  "innerException": {
    "message": "An error has occurred.",
    "exceptionMessage": "The requested service 'OnionWebApiStarterKit.Data.ISchoolDbContext' has not been registered. To avoid this exception, either register a component to provide the service, check for service registration using IsRegistered(), or use the ResolveOptional() method to resolve an optional dependency.",
    "exceptionType": "Autofac.Core.Registration.ComponentNotRegisteredException",
    "stackTrace": "   at Autofac.ResolutionExtensions.ResolveService(IComponentContext context, Service service, IEnumerable`1 parameters)\r\n   at Autofac.ResolutionExtensions.Resolve(IComponentContext context, Type serviceType, IEnumerable`1 parameters)\r\n   at Autofac.ResolutionExtensions.Resolve[TService](IComponentContext context, IEnumerable`1 parameters)\r\n   at Autofac.ResolutionExtensions.Resolve[TService](IComponentContext context)\r\n   at OnionWebApiStarterKit.Bootstrapper.IdentityModule.<>c.<Load>b__2_0(IComponentContext b) in C:\\Projects\\OnionWebApiStarterKit\\OnionWebApiStarterKit.Bootstrapper\\App_Start\\IdentityModule.cs:line 33\r\n   at Autofac.RegistrationExtensions.<>c__DisplayClass10`1.<Register>b__f(IComponentContext c, IEnumerable`1 p)\r\n   at Autofac.Builder.RegistrationBuilder.<>c__DisplayClass1`1.<ForDelegate>b__0(IComponentContext c, IEnumerable`1 p)\r\n   at Autofac.Core.Activators.Delegate.DelegateActivator.ActivateInstance(IComponentContext context, IEnumerable`1 parameters)\r\n   at Autofac.Core.Resolving.InstanceLookup.Activate(IEnumerable`1 parameters)\r\n   at Autofac.Core.Resolving.InstanceLookup.<Execute>b__0()\r\n   at Autofac.Core.Lifetime.LifetimeScope.GetOrCreateAndShare(Guid id, Func`1 creator)\r\n   at Autofac.Core.Resolving.InstanceLookup.Execute()\r\n   at Autofac.Core.Resolving.ResolveOperation.GetOrCreateInstance(ISharingLifetimeScope currentOperationScope, IComponentRegistration registration, IEnumerable`1 parameters)\r\n   at Autofac.Core.Resolving.InstanceLookup.ResolveComponent(IComponentRegistration registration, IEnumerable`1 parameters)\r\n   at Autofac.Core.Registration.ExternalRegistrySource.<>c__DisplayClass8.<RegistrationsFor>b__3(IComponentContext c, IEnumerable`1 p)\r\n   at Autofac.Core.Activators.Delegate.DelegateActivator.ActivateInstance(IComponentContext context, IEnumerable`1 parameters)\r\n   at Autofac.Core.Resolving.InstanceLookup.Activate(IEnumerable`1 parameters)\r\n   at Autofac.Core.Resolving.InstanceLookup.Execute()\r\n   at Autofac.Core.Resolving.ResolveOperation.GetOrCreateInstance(ISharingLifetimeScope currentOperationScope, IComponentRegistration registration, IEnumerable`1 parameters)\r\n   at Autofac.Core.Resolving.InstanceLookup.ResolveComponent(IComponentRegistration registration, IEnumerable`1 parameters)\r\n   at Autofac.ResolutionExtensions.TryResolveService(IComponentContext context, Service service, IEnumerable`1 parameters, Object& instance)\r\n   at Autofac.ResolutionExtensions.ResolveService(IComponentContext context, Service service, IEnumerable`1 parameters)\r\n   at Autofac.ResolutionExtensions.Resolve(IComponentContext context, Type serviceType, IEnumerable`1 parameters)\r\n   at Autofac.ResolutionExtensions.Resolve[TService](IComponentContext context, IEnumerable`1 parameters)\r\n   at Autofac.ResolutionExtensions.Resolve[TService](IComponentContext context)\r\n   at OnionWebApiStarterKit.Bootstrapper.IdentityModule.<>c.<Load>b__2_1(IComponentContext b) in C:\\Projects\\OnionWebApiStarterKit\\OnionWebApiStarterKit.Bootstrapper\\App_Start\\IdentityModule.cs:line 37\r\n   at Autofac.RegistrationExtensions.<>c__DisplayClass10`1.<Register>b__f(IComponentContext c, IEnumerable`1 p)\r\n   at Autofac.Builder.RegistrationBuilder.<>c__DisplayClass1`1.<ForDelegate>b__0(IComponentContext c, IEnumerable`1 p)\r\n   at Autofac.Core.Activators.Delegate.DelegateActivator.ActivateInstance(IComponentContext context, IEnumerable`1 parameters)\r\n   at Autofac.Core.Resolving.InstanceLookup.Activate(IEnumerable`1 parameters)\r\n   at Autofac.Core.Resolving.InstanceLookup.<Execute>b__0()\r\n   at Autofac.Core.Lifetime.LifetimeScope.GetOrCreateAndShare(Guid id, Func`1 creator)\r\n   at Autofac.Core.Resolving.InstanceLookup.Execute()\r\n   at Autofac.Core.Resolving.ResolveOperation.GetOrCreateInstance(ISharingLifetimeScope currentOperationScope, IComponentRegistration registration, IEnumerable`1 parameters)\r\n   at Autofac.Core.Resolving.InstanceLookup.ResolveComponent(IComponentRegistration registration, IEnumerable`1 parameters)\r\n   at Autofac.Core.Registration.ExternalRegistrySource.<>c__DisplayClass8.<RegistrationsFor>b__3(IComponentContext c, IEnumerable`1 p)\r\n   at Autofac.Core.Activators.Delegate.DelegateActivator.ActivateInstance(IComponentContext context, IEnumerable`1 parameters)\r\n   at Autofac.Core.Resolving.InstanceLookup.Activate(IEnumerable`1 parameters)\r\n   at Autofac.Core.Resolving.InstanceLookup.Execute()\r\n   at Autofac.Core.Resolving.ResolveOperation.GetOrCreateInstance(ISharingLifetimeScope currentOperationScope, IComponentRegistration registration, IEnumerable`1 parameters)\r\n   at Autofac.Core.Resolving.InstanceLookup.ResolveComponent(IComponentRegistration registration, IEnumerable`1 parameters)\r\n   at Autofac.Core.Activators.Reflection.AutowiringParameter.<>c__DisplayClass2.<CanSupplyValue>b__0()\r\n   at Autofac.Core.Activators.Reflection.ConstructorParameterBinding.Instantiate()\r\n   at Autofac.Core.Activators.Reflection.ReflectionActivator.ActivateInstance(IComponentContext context, IEnumerable`1 parameters)\r\n   at Autofac.Core.Resolving.InstanceLookup.Activate(IEnumerable`1 parameters)\r\n   at Autofac.Core.Resolving.InstanceLookup.<Execute>b__0()\r\n   at Autofac.Core.Lifetime.LifetimeScope.GetOrCreateAndShare(Guid id, Func`1 creator)\r\n   at Autofac.Core.Resolving.InstanceLookup.Execute()\r\n   at Autofac.Core.Resolving.ResolveOperation.GetOrCreateInstance(ISharingLifetimeScope currentOperationScope, IComponentRegistration registration, IEnumerable`1 parameters)\r\n   at Autofac.Core.Resolving.InstanceLookup.ResolveComponent(IComponentRegistration registration, IEnumerable`1 parameters)\r\n   at Autofac.Core.Registration.ExternalRegistrySource.<>c__DisplayClass8.<RegistrationsFor>b__3(IComponentContext c, IEnumerable`1 p)\r\n   at Autofac.Core.Activators.Delegate.DelegateActivator.ActivateInstance(IComponentContext context, IEnumerable`1 parameters)\r\n   at Autofac.Core.Resolving.InstanceLookup.Activate(IEnumerable`1 parameters)\r\n   at Autofac.Core.Resolving.InstanceLookup.Execute()\r\n   at Autofac.Core.Resolving.ResolveOperation.GetOrCreateInstance(ISharingLifetimeScope currentOperationScope, IComponentRegistration registration, IEnumerable`1 parameters)\r\n   at Autofac.Core.Resolving.InstanceLookup.ResolveComponent(IComponentRegistration registration, IEnumerable`1 parameters)\r\n   at Autofac.Core.Activators.Reflection.AutowiringParameter.<>c__DisplayClass2.<CanSupplyValue>b__0()\r\n   at Autofac.Core.Activators.Reflection.ConstructorParameterBinding.Instantiate()\r\n   at Autofac.Core.Activators.Reflection.ReflectionActivator.ActivateInstance(IComponentContext context, IEnumerable`1 parameters)\r\n   at Autofac.Core.Resolving.InstanceLookup.Activate(IEnumerable`1 parameters)\r\n   at Autofac.Core.Resolving.InstanceLookup.Execute()\r\n   at Autofac.Core.Resolving.ResolveOperation.GetOrCreateInstance(ISharingLifetimeScope currentOperationScope, IComponentRegistration registration, IEnumerable`1 parameters)\r\n   at Autofac.Core.Resolving.InstanceLookup.ResolveComponent(IComponentRegistration registration, IEnumerable`1 parameters)\r\n   at Autofac.Core.Registration.ExternalRegistrySource.<>c__DisplayClass8.<RegistrationsFor>b__3(IComponentContext c, IEnumerable`1 p)\r\n   at Autofac.Core.Activators.Delegate.DelegateActivator.ActivateInstance(IComponentContext context, IEnumerable`1 parameters)\r\n   at Autofac.Core.Resolving.InstanceLookup.Activate(IEnumerable`1 parameters)\r\n   at Autofac.Core.Resolving.InstanceLookup.Execute()\r\n   at Autofac.Core.Resolving.ResolveOperation.GetOrCreateInstance(ISharingLifetimeScope currentOperationScope, IComponentRegistration registration, IEnumerable`1 parameters)\r\n   at Autofac.Core.Resolving.ResolveOperation.ResolveComponent(IComponentRegistration registration, IEnumerable`1 parameters)\r\n   at Autofac.Core.Resolving.ResolveOperation.Execute(IComponentRegistration registration, IEnumerable`1 parameters)\r\n   at Autofac.Core.Lifetime.LifetimeScope.ResolveComponent(IComponentRegistration registration, IEnumerable`1 parameters)\r\n   at Autofac.ResolutionExtensions.TryResolveService(IComponentContext context, Service service, IEnumerable`1 parameters, Object& instance)\r\n   at Autofac.ResolutionExtensions.ResolveOptionalService(IComponentContext context, Service service, IEnumerable`1 parameters)\r\n   at Autofac.ResolutionExtensions.ResolveOptional(IComponentContext context, Type serviceType, IEnumerable`1 parameters)\r\n   at Autofac.ResolutionExtensions.ResolveOptional(IComponentContext context, Type serviceType)\r\n   at Autofac.Integration.WebApi.AutofacWebApiDependencyScope.GetService(Type serviceType)\r\n   at System.Web.Http.Dispatcher.DefaultHttpControllerActivator.GetInstanceOrActivator(HttpRequestMessage request, Type controllerType, Func`1& activator)\r\n   at System.Web.Http.Dispatcher.DefaultHttpControllerActivator.Create(HttpRequestMessage request, HttpControllerDescriptor controllerDescriptor, Type controllerType)"
  }

我正在从我的引导启动类注册我的依赖项：

IocConfig.RegisterDependencies(app);

我确认它确实通过设置断点而受到打击。 以下是我的注册：

public static void RegisterDependencies(IAppBuilder app)
{
    DbContextScopeExtensionConfig.Setup();

    // Get your HttpConfiguration. In OWIN, you'll create one
    // rather than using GlobalConfiguration.
    var config = new HttpConfiguration();

    // register Auto Mapper
    AutoMapperConfig.Initialize();

    // register api routing.
    WebApiConfig.Register(config);

    // Run optional steps, like registering filters,
    // per-controller-type services, etc. 

    var builder = new ContainerBuilder();

    // Register Web API controller in executing assembly.
       builder.RegisterApiControllers(Assembly.Load("OnionWebApiStarterKit.WebApi"));

    //Helper nuget for managing the DbContext lifetime in Entity Framework. Please see: http://mehdi.me/ambient-dbcontext-in-ef6/
    builder.RegisterType<DbContextScopeFactory>().As<IDbContextScopeFactory>().SingleInstance();
    builder.RegisterType<AmbientDbContextLocator>().As<IAmbientDbContextLocator>().SingleInstance();

    // Registers our IMediator (abstraction for observer pattern, which lets us use CQRS)
    builder.RegisterModule(new MediatorModule(Assembly.Load("OnionWebApiStarterKit.Services")));

    // Registers our Fluent Validations that we use on our Models
    builder.RegisterModule(new FluentValidationModule(Assembly.Load("OnionWebApiStarterKit.WebApi"), Assembly.Load("OnionWebApiStarterKit.Services")));

    // Registers our AutoMapper Profiles
    builder.RegisterModule(new AutoMapperModule(Assembly.Load("OnionWebApiStarterKit.WebApi"), Assembly.Load("OnionWebApiStarterKit.Services")));

    // Registers our ASP.NET Identity custom classes.
    builder.RegisterModule(new IdentityModule(Assembly.Load("OnionWebApiStarterKit.Data"), Assembly.Load("OnionWebApiStarterKit.Core")));

    // Set the dependency resolver to be Autofac.
    var container = builder.Build();

    // helps view registered autofac dependencies.
    // container.IsRegistered();

    config.DependencyResolver = new AutofacWebApiDependencyResolver(container);

    // Register the Autofac middleware FIRST, then the Autofac Web API middleware,
    // and finally the standard Web API middleware.
    app.UseAutofacMiddleware(container);
    app.UseAutofacWebApi(config);
    app.UseCors(CorsOptions.AllowAll); // Enables crossdomain requests
    app.UseWebApi(config);

}

在上面的文件中，下面的模块处理身份注册， IApplicationUserManager 是其中的一部分：

// Registers our ASP.NET Identity custom classes.
            builder.RegisterModule(new IdentityModule(Assembly.Load("OnionWebApiStarterKit.Data"), Assembly.Load("OnionWebApiStarterKit.Core")));

这是我的身份信息的注册方式：

public IdentityModule(params System.Reflection.Assembly[] assembliesToScan)
    : base()
{
    _assembliesToScan = assembliesToScan;
}

protected override void Load(ContainerBuilder builder)
{       
    builder.RegisterType(typeof(ApplicationUserManager)).As(typeof(IApplicationUserManager)).InstancePerRequest();
    builder.RegisterType(typeof(ApplicationRoleManager)).As(typeof(IApplicationRoleManager)).InstancePerRequest();
    builder.RegisterType(typeof(ApplicationIdentityUser)).As(typeof(IUser<int>)).InstancePerRequest();

    builder.Register(b => b.Resolve<ISchoolDbContext>() as DbContext).InstancePerRequest();

    builder.Register(b =>
    {
        var manager = IdentityFactory.CreateUserManager(b.Resolve<DbContext>());

        if (Startup.DataProtectionProvider != null)
        {
            manager.UserTokenProvider =
                new DataProtectorTokenProvider<ApplicationIdentityUser, int>(
                    Startup.DataProtectionProvider.Create("ASP.NET Identity"));
        }
        return manager;
    }).InstancePerRequest();

    builder.Register(b => IdentityFactory.CreateRoleManager(b.Resolve<DbContext>())).InstancePerRequest();

    builder.Register(b => HttpContext.Current.Request.GetOwinContext().Authentication).InstancePerRequest();        
}

如您所见，ISCoolDbContext 清楚地在这一行注册：

 builder.Register(b => b.Resolve<ISchoolDbContext>() as DbContext).InstancePerRequest();

这是 Autofac 在堆栈跟踪中抱怨的同一行：

在 OnionWebApiStarterKit.Bootstrapper.IdentityModule.<>c.b__2_0(IComponentContext b) 在 C:\\Projects\\OnionWebApiStarterKit\\OnionWebApiStarterKit.Bootstrapper\\App_Start\\IdentityModule.cs:line 33

我有点不明白为什么注入 IApplicationUserManager 会告诉我我没有注册我的 ISchoolDbContext？

谢谢。

更新

看起来我没有扫描 IdentityModule 中传入的程序集。 所以，我已经相应地更新了我的代码：

// Register our UserManager
builder.RegisterAssemblyTypes(_assembliesToScan)
    .As<IApplicationUserManager>().InstancePerRequest();

//// Register our RoleManager
builder.RegisterAssemblyTypes(_assembliesToScan)
    .As<IApplicationRoleManager>().InstancePerRequest();

builder.RegisterAssemblyTypes(_assembliesToScan)
    .As<IUser<int>>().InstancePerRequest();

Answer 1

我假设您有一个用于数据库操作的持久层或类似的类库。 您是否在该程序集中注册了所有类型？ 像下面这样：

           var assembly = typeof(DbContextScopeFactory).Assembly;
            builder.RegisterAssemblyTypes(assembly).AsImplementedInterfaces();

            builder.RegisterAssemblyTypes(assembly)
                   .Where(t => t.Name.StartsWith("SomeInterface"))
                   .AsImplementedInterfaces();
            builder.RegisterAssemblyTypes(assembly)
                   .Where(t => t.Name.EndsWith("DbContext"))
                   .AsImplementedInterfaces();