与 Autofac 集成时 C# ASP.Net Core 面临的问题答案

【问题标题】：C# ASP.Net Core facing issues when integrating with Autofac与 Autofac 集成时 C# ASP.Net Core 面临的问题
【发布时间】：2018-07-09 18:26:18
【问题描述】：

我有一个控制器 DailyExpenseController，我将 IQueryExecutor 类注入到控制器中。

DailyExpenseController

using HomeBudgetTrackingSystem.CrossCutting;
using HomeBudgetTrackingSystem.DTO;
using HomeBudgetTrackingSystem.Models;
using HomeBudgetTrackingSystem.Query;
using Microsoft.AspNetCore.Mvc;
using System.Threading.Tasks;

namespace HomeBudgetTrackingSystem.Controllers
{
    [Produces("application/json")]
    [Route("api/DailyExpense/{Id}")]
    public class DailyExpenseController : Controller
    {
        private readonly IQueryExecutor queryExecutor;

        public DailyExpenseController(IQueryExecutor queryExecutor)
        {
            this.queryExecutor = queryExecutor;
        }

        [HttpPost]
        [Route("Create")]
        public async Task<IActionResult> CreateExpense(long Id, [FromBody] Expenditure expenditure)
        {
            var findEntity = new FindEntityQuery<Expense>(Id);
            var find = queryExecutor.Execute(findEntity);

            /*if (find == null)
                return NotFound();*/


            var createExpenses = new CreateExpenditure(expenditure);
            var expenses = queryExecutor.Execute(createExpenses);
            return Ok(expenses);
        }

        /*If I write this method, it will result in 500 Error, because this method has id which is confusing 
         with the variable Id declared with Controller*/
        /*[HttpGet("{id}")]
        public string Get(int id)
        {
            return "value";
        }*/

        [HttpGet("{id2}")]
        public string Get(long id)
        {
            return "value";
        }

        [HttpPost]
        public void Post([FromBody]string value)
        {
        }

    }
}

以下是我的 Autofac 配置详细信息

Startup.cs

using Autofac;
using Autofac.Extensions.DependencyInjection;
using HomeBudgetTrackingSystem.Repository;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using System;

namespace HomeBudgetTrackingSystem
{
    public class Startup
    {
        public Startup(IConfiguration configuration)
        {
            Configuration = configuration;
        }

        public IConfiguration Configuration { get; }

        // This method gets called by the runtime. Use this method to add services to the container.
        //public void ConfigureServices(IServiceCollection services)
        public IServiceProvider ConfigureServices(IServiceCollection services)
        {
            services.AddMvc();
            /*services.AddDbContext<BudgetContext>(options =>
             options.UseSqlServer(Configuration.GetConnectionString("BudgetConnection")
        )); */

            var builder = new ContainerBuilder();
            builder.Populate(services);
            builder.RegisterModule(new RepositoryHandlerModule());
            //builder.RegisterType<QueryExecutor>().As<IQueryExecutor>();
            ApplicationContainer = builder.Build();
            return new AutofacServiceProvider(ApplicationContainer);
        }

        public IContainer ApplicationContainer { get; private set; }

        // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
        public void Configure(IApplicationBuilder app, IHostingEnvironment env, IApplicationLifetime appLifetime)
        {
            if (env.IsDevelopment())
            {
                app.UseDeveloperExceptionPage();
            }

            app.UseMvc();
            appLifetime.ApplicationStopped.Register(() => ApplicationContainer.Dispose());
        }
    }
}

下面是我注册依赖项的模型生成器类

RepositoryHandlerModule.cs

using Autofac;
using HomeBudgetTrackingSystem.CrossCutting;

namespace HomeBudgetTrackingSystem.Repository
{
    public class RepositoryHandlerModule : Module
    {
        protected override void Load(ContainerBuilder builder)
        {
            builder.RegisterType<QueryExecutor>().As<IQueryExecutor>().InstancePerRequest();
        }
    }
}

我没有对 Program.cs 进行任何更改

程序.cs

using Microsoft.AspNetCore;
using Microsoft.AspNetCore.Hosting;

namespace HomeBudgetTrackingSystem
{
    public class Program
    {
        public static void Main(string[] args)
        {
            BuildWebHost(args).Run();
        }

        public static IWebHost BuildWebHost(string[] args) =>
            WebHost.CreateDefaultBuilder(args)
                .UseStartup<Startup>()
                .Build();
    }
}

以下是我收到的异常详情

Autofac.Core.DependencyResolutionException：无法解析类型“HomeBudgetTrackingSystem.CrossCutting.QueryExecutor”，因为无法找到它所属的生命周期范围。此注册公开了以下服务： - HomeBudgetTrackingSystem.CrossCutting.IQueryExecutor

详细信息 ---> 从请求实例的范围中看不到带有匹配“AutofacWebRequest”标签的范围。

如果您在执行 Web 应用程序期间看到此情况，通常表示注册为 per-HTTP 请求的组件正在被 SingleInstance() 组件（或类似场景）请求。在 Web 集成下，总是从依赖解析器或请求生命周期范围请求依赖，而不是从容器本身。（有关详细信息，请参阅内部异常。）---> Autofac.Core.DependencyResolutionException：从请求实例的范围内看不到带有匹配“AutofacWebRequest”标签的范围。

如果您在执行 Web 应用程序期间看到此情况，通常表示注册为 per-HTTP 请求的组件正在被 SingleInstance() 组件（或类似场景）请求。在 Web 集成下，总是从依赖解析器或请求生命周期范围请求依赖，而不是从容器本身。在 Autofac.Core.Lifetime.MatchingScopeLifetime.FindScope(ISharingLifetimeScope mostNestedVisibleScope) 在 Autofac.Core.Resolving.InstanceLookup..ctor（IComponentRegistration 注册，IResolveOperation 上下文，ISharingLifetimeScope mostNestedVisibleScope，IEnumerable1 parameters) --- End of inner exception stack trace --- at Autofac.Core.Resolving.InstanceLookup..ctor(IComponentRegistration registration, IResolveOperation context, ISharingLifetimeScope mostNestedVisibleScope, IEnumerable1 参数）在 Autofac.Core.Resolving.ResolveOperation.GetOrCreateInstance（ISharingLifetimeScope currentOperationScope，IComponentRegistration 注册，IEnumerable1 parameters) at Autofac.Core.Resolving.ResolveOperation.Execute(IComponentRegistration registration, IEnumerable1 参数）在 Autofac.ResolutionExtensions.TryResolveService（IComponentContext 上下文，服务服务，IEnumerable1 parameters, Object& instance) at Autofac.ResolutionExtensions.ResolveOptionalService(IComponentContext context, Service service, IEnumerable1 参数）在 Microsoft.Extensions.Internal.ActivatorUtilities.GetService（IServiceProvider sp，类型类型，类型 requiredBy，布尔 isDefaultParameterRequired）在 lambda_method（闭包，IServiceProvider，对象 []）在 Microsoft.AspNetCore.Mvc.Controllers.ControllerActivatorProvider.c__DisplayClass4_0.b__0(ControllerContext controllerContext) 在 Microsoft.AspNetCore.Mvc.Controllers.ControllerFactoryProvider.c__DisplayClass5_0.g__CreateController|0(ControllerContext controllerContext) 在 Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker.Next（状态&下一个，范围&范围，对象&状态，布尔& isCompleted）在 Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker.d__14.MoveNext() --- 从先前抛出异常的位置结束堆栈跟踪 --- 在 System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw() 在 System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification（任务任务）在 Microsoft.AspNetCore.Mvc.Internal.ResourceInvoker.d__22.MoveNext() --- 从先前抛出异常的位置结束堆栈跟踪 --- 在 System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw() 在 Microsoft.AspNetCore.Mvc.Internal.ResourceInvoker.Rethrow（ResourceExecutedContext 上下文）在 Microsoft.AspNetCore.Mvc.Internal.ResourceInvoker.Next（状态&下一个，范围&范围，对象&状态，布尔& isCompleted）在 Microsoft.AspNetCore.Mvc.Internal.ResourceInvoker.d__17.MoveNext() --- 从先前抛出异常的位置结束堆栈跟踪 --- 在 System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw() 在 System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification（任务任务）在 Microsoft.AspNetCore.Mvc.Internal.ResourceInvoker.d__15.MoveNext() --- 从先前抛出异常的位置结束堆栈跟踪 --- 在 System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw() 在 System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification（任务任务）在 Microsoft.AspNetCore.Builder.RouterMiddleware.d__4.MoveNext() --- 从先前抛出异常的位置结束堆栈跟踪 --- 在 System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw() 在 System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification（任务任务）在 Microsoft.AspNetCore.Diagnostics.DeveloperExceptionPageMiddleware.d__7.MoveNext()

我已经提到了这些的多个链接。比较突出的是

http://autofac.readthedocs.io/en/latest/faq/per-request-scope.html http://autofac.readthedocs.io/en/latest/integration/aspnetcore.html （我更喜欢没有容器的配置） http://www.codedigest.com/posts/49/using-autofac-instead-of-inbuilt-di-container-with-in-aspnet-core-mvc（这是我介绍的）

谁能帮我解决这些问题？

【问题讨论】：

标签： c# dependency-injection autofac asp.net-core-1.1

【解决方案1】：

我能够找到问题的解决方案。

http://autofaccn.readthedocs.io/en/latest/integration/aspnetcore.html

在标题“与 ASP.NET 经典的区别”下，列出了一个关键点使用 InstancePerLifetimeScope 而不是 InstancePerRequest。

我还对我的 RepositoryHandlerModule.cs 进行了更改，例如添加 BudgetContext.cs 如下

public class RepositoryHandlerModule : Module
    {
        protected override void Load(ContainerBuilder builder)
        {
            base.Load(builder);
            builder.RegisterType<QueryExecutor>().As<IQueryExecutor>().InstancePerLifetimeScope();
            builder.RegisterType<BudgetContext>().InstancePerLifetimeScope();
        }
    }

【讨论】：