带有 ASP.Identity 的 AutoFac

Question

我将 AutoFac 3.5 与 WebApi Integration 3.3 和 Asp.Identity 2.0.1 结合使用。问题是当我将 MyDbContext 指定为 InstancePerRequest 时，Asp.Net 身份存在问题。然后我得到了这种错误信息：

从请求实例的范围中看不到带有与“AutofacWebRequest”匹配的标记的范围。这通常表明注册为 per-HTTP 请求的组件正在由 SingleInstance() 组件（或类似场景）请求。在 Web 集成下，始终从 DependencyResolver.Current 或 ILifetimeScopeProvider.RequestLifetime 请求依赖项，而不是从容器本身.

我正在像这样注册 Asp 令牌提供程序：

public partial class Startup
{
    static Startup()
    {
        OAuthOptions = new OAuthAuthorizationServerOptions
        {
            TokenEndpointPath = new PathString("/token"),
            RefreshTokenProvider = (IAuthenticationTokenProvider)GlobalConfiguration.Configuration.DependencyResolver.GetService(typeof(IAuthenticationTokenProvider)),
            Provider = (IOAuthAuthorizationServerProvider)GlobalConfiguration.Configuration.DependencyResolver.GetService(typeof(IOAuthAuthorizationServerProvider)),
            AuthorizeEndpointPath = new PathString("/api/Account/ExternalLogin"),
            AccessTokenExpireTimeSpan = TimeSpan.FromHours(1),
            AllowInsecureHttp = true
        };
    }

    public void ConfigureAuth(IAppBuilder app)
    {
        app.UseOAuthBearerTokens(OAuthOptions);
    }
}

AutoFac 部分如下所示：

builder.RegisterType<MyDbContext>().As<DbContext>().InstancePerRequest();
builder.RegisterType<SimpleRefreshToken>().As<IAuthenticationTokenProvider>();
builder.Register(x => new ApplicationOAuthProvider(
                        "self",
                        x.Resolve<Func<UserManager<User>>>()).As<IOAuthAuthorizationServerProvider>();

有人解决了这个问题吗？我找到了这个旧帖子ASP.net Identity, IoC and sharing DbContext

编辑

还有这篇博客文章，其中包含一个凌乱的解决方法http://blogs.msdn.com/b/webdev/archive/2014/02/12/per-request-lifetime-management-for-usermanager-class-in-asp-net-identity.aspx

Answer 1

我能够通过从 OwinContext 中获取 AutofacWebRequest 并解析 UserManager 来解决问题。

IOwinContext 被传递给每个 OwinMiddleware 的 Invoke 方法。在里面您可以找到作为 IDictionary 的 Enviroment 属性，其中包含大量信息，包括“autofac:OwinLifetimeScope”。 你可以得到这个 LifetimeScope，它应该用标签“AutofacWebRequest”指定，因为它是为每个 http 请求创建的嵌套 Scope，并解析你需要的对象类型。

我的实现看起来与此类似。注意我在 UserManagerFactory 中生成 UserManager 类的方式。

public class Startup
{
    static Startup()
    {
        PublicClientId = "self";

        UserManagerFactory = () =>
        {
            //get current Http request Context
            var owinContext = HttpContext.Current.Request.GetOwinContext();

            //get OwinLifetimeScope, in this case will be "AutofacWebRequest"
            var requestScope = owinContext.Environment.ContainsKey("autofac:OwinLifetimeScope");

            if (!owinContext.Environment.Any(a => a.Key == "autofac:OwinLifetimeScope" && a.Value != null))
                throw new Exception("RequestScope cannot be null...");

            Autofac.Core.Lifetime.LifetimeScope scope = owinContext.Environment.FirstOrDefault(f => f.Key == "autofac:OwinLifetimeScope").Value as Autofac.Core.Lifetime.LifetimeScope;

            return scope.GetService(typeof(UserManager<Models.UserModel>)) as UserManager<Models.UserModel>;

        };

        OAuthOptions = new OAuthAuthorizationServerOptions
        {
            TokenEndpointPath = new PathString("/Token"),
            Provider = new ApplicationOAuthProviderCustom(PublicClientId, UserManagerFactory),
            AuthorizeEndpointPath = new PathString("/api/Account/ExternalLogin"),
            AccessTokenExpireTimeSpan = TimeSpan.FromDays(14),
            AllowInsecureHttp = true
        };
    }

    public static OAuthAuthorizationServerOptions OAuthOptions { get; private set; }

    public static Func<UserManager<Models.UserModel>> UserManagerFactory { get; set; }

    public static string PublicClientId { get; private set; }

    public void Configuration(IAppBuilder app)
    {

        var builder = new ContainerBuilder();

        builder.RegisterApiControllers(Assembly.GetExecutingAssembly());

        builder.RegisterType<UserModelsConvert>().InstancePerApiRequest();
        builder.RegisterType<UserStoreCustom>().As<IUserStore<Models.UserModel>>().InstancePerApiRequest();
        builder.RegisterType<UserManager<Models.UserModel>>().InstancePerApiRequest();

        //loading other projects
        builder.RegisterModule(new LogicModule());

        var container = builder.Build();

        app.UseAutofacMiddleware(container);

        //// Create the depenedency resolver.
        var resolver = new AutofacWebApiDependencyResolver(container);

        // Configure Web API with the dependency resolver
        GlobalConfiguration.Configuration.DependencyResolver = resolver;

        app.UseOAuthBearerTokens(OAuthOptions);

        //extend lifetime scope to Web API
        app.UseAutofacWebApi(GlobalConfiguration.Configuration);

        //app.UseWebApi(config);

    }
}

我希望这会有所帮助。如果遗漏了什么，请告诉我。