有什么方法可以在全局 asax 应用程序启动之前将 owin startup.cs 配置为运行吗？

Question

我正在尝试在 MVC 5 中实现按请求容器和按请求事务模式。我已经利用全局 asax 为其编写了大部分代码。我在创建多个上下文时遇到了问题，因为 owin 正在创建新的 DbContext 类作为其 startup.cs 的一部分。有什么办法可以在全局 asax 应用程序启动事件之前拥有 owin 运行，以便我可以检索在那里创建的现有上下文？我是这些模式的新手，所以如果这个问题听起来不对，我愿意接受其他建议。

public IContainer Container
{
    get
    {
        return (IContainer)HttpContext.Current.Items["_Container"];
    }
    set
    {
        HttpContext.Current.Items["_Container"] = value;
    }
}

protected void Application_Start()
{
    AreaRegistration.RegisterAllAreas();
    FilterConfig.RegisterGlobalFilters(GlobalFilters.Filters);
    RouteConfig.RegisterRoutes(RouteTable.Routes);
    BundleConfig.RegisterBundles(BundleTable.Bundles);

    ////Database.SetInitializer(new MigrateDatabaseToLatestVersion<ApplicationDbContext, Configuration>());


    DependencyResolver.SetResolver(
        new StructureMapDependencyResolver(() => Container ?? IoC.Container));

    IoC.Container.Configure(cfg =>
    {
        cfg.AddRegistry(new StandardRegistry());
        cfg.AddRegistry(new ControllerRegistry());
        cfg.AddRegistry(new ActionFilterRegistry(
            () => Container ?? IoC.Container));
        cfg.AddRegistry(new MvcRegistry());
        cfg.AddRegistry(new TaskRegistry());
        cfg.AddRegistry(new ModelMetadataRegistry());
    });

    using (var container = IoC.Container.GetNestedContainer())
    {

        foreach (var task in container.GetAllInstances<IRunAtInit>())
        {
            task.Execute();
        }

        foreach (var task in container.GetAllInstances<IRunAtStartup>())
        {
            task.Execute();
        }
    }
}

public void Application_BeginRequest()
{
    Container = IoC.Container.GetNestedContainer();

    foreach (var task in Container.GetAllInstances<IRunOnEachRequest>())
    {
        task.Execute();
    }
}

public void Application_Error()
{
    foreach (var task in Container.GetAllInstances<IRunOnError>())
    {
        task.Execute();
    }
}

public void Application_EndRequest()
{
    try
    {
        foreach (var task in
            Container.GetAllInstances<IRunAfterEachRequest>())
        {
            task.Execute();
        }
    }
    finally
    {
        Container.Dispose();
        Container = null;
    }
}

结构图Class

public class StructureMapDependencyResolver : IDependencyResolver
{
    private readonly Func<IContainer> _factory;

    public StructureMapDependencyResolver(Func<IContainer> factory)
    {
        _factory = factory;
    }

    public object GetService(Type serviceType)
    {
        if (serviceType == null)
        {
            return null;
        }

        var factory = _factory();

        return serviceType.IsAbstract || serviceType.IsInterface
            ? factory.TryGetInstance(serviceType)
            : factory.GetInstance(serviceType);
    }

    public IEnumerable<object> GetServices(Type serviceType)
    {
        return _factory().GetAllInstances(serviceType).Cast<object>();
    }

Owin 启动 - 这在全局 ASAX 启动和每个请求之后执行，但在全局 ASAX 代码之后。我希望能够将 OWIN 上下文设置为现有上下文实例，或者首先执行此代码并获取在启动时创建的上下文。

    // For more information on configuring authentication, please visit https://go.microsoft.com/fwlink/?LinkId=301864
    public void ConfigureAuth(IAppBuilder app)
    {

        // Configure the db context, user manager and signin manager to use a single instance per request
        app.CreatePerOwinContext(ApplicationDbContext.Create);
        app.CreatePerOwinContext<ApplicationUserManager>(ApplicationUserManager.Create);
        app.CreatePerOwinContext<ApplicationSignInManager>(ApplicationSignInManager.Create);

        // Enable the application to use a cookie to store information for the signed in user
        // and to use a cookie to temporarily store information about a user logging in with a third party login provider
        // Configure the sign in cookie
        app.UseCookieAuthentication(new CookieAuthenticationOptions
        {
            AuthenticationType = DefaultAuthenticationTypes.ApplicationCookie,
            LoginPath = new PathString("/Account/Login"),
            Provider = new CookieAuthenticationProvider
            {
                // Enables the application to validate the security stamp when the user logs in.
                // This is a security feature which is used when you change a password or add an external login to your account.  
                OnValidateIdentity = SecurityStampValidator.OnValidateIdentity<ApplicationUserManager, ApplicationUser>(
                    validateInterval: TimeSpan.FromMinutes(30),
                    regenerateIdentity: (manager, user) => user.GenerateUserIdentityAsync(manager))
            }
        });            
        app.UseExternalSignInCookie(DefaultAuthenticationTypes.ExternalCookie);

        // Enables the application to temporarily store user information when they are verifying the second factor in the two-factor authentication process.
        app.UseTwoFactorSignInCookie(DefaultAuthenticationTypes.TwoFactorCookie, TimeSpan.FromMinutes(5));

        // Enables the application to remember the second login verification factor such as phone or email.
        // Once you check this option, your second step of verification during the login process will be remembered on the device where you logged in from.
        // This is similar to the RememberMe option when you log in.
        app.UseTwoFactorRememberBrowserCookie(DefaultAuthenticationTypes.TwoFactorRememberBrowserCookie);

        // Uncomment the following lines to enable logging in with third party login providers
        //app.UseMicrosoftAccountAuthentication(
        //    clientId: "",
        //    clientSecret: "");

        //app.UseTwitterAuthentication(
        //   consumerKey: "",
        //   consumerSecret: "");

        //app.UseFacebookAuthentication(
        //   appId: "",
        //   appSecret: "");

        //app.UseGoogleAuthentication(new GoogleOAuth2AuthenticationOptions()
        //{
        //    ClientId = "",
        //    ClientSecret = ""
        //});
    }
}

Answer 1

对于 MVC 5，OWIN 将始终运行在 global.asax Application_Start() 之后。那是因为 MVC 应用程序承载了 OWIN。让 OWIN 处理配置和启动要容易得多，App_Start 仅用于 MVC 注册。因此，我建议将您的容器注册和启动移动到 Startup。像这样：

public partial class Startup
{
    public void Configuration(IAppBuilder app)
    {
        DependencyResolver.SetResolver(
            new StructureMapDependencyResolver(IoC.Container));

        IoC.Container.Configure(cfg =>
        {
           ...
        });

        using (var container = IoC.Container.GetNestedContainer())
        {
            foreach (var task in container.GetAllInstances<IRunAtInit>())
            {
                task.Execute();
            }

            foreach (var task in container.GetAllInstances<IRunAtStartup>())
            {
                task.Execute();
            }
        }
    }
}

然后，在 Application_BeginRequest、Application_EndRequest 和 Application_Error 中，您通过 DependencyResolver 访问容器。例如：

public void Application_BeginRequest()
{
    foreach (var task in DependencyResolver.Current.GetServices<IRunOnEachRequest>())
    {
        task.Execute();
    }
}

请注意，不再有 Container 属性，随后也没有嵌套容器（启动时的容器除外）。那是因为你的问题比管道时间更微妙。每个请求模式的容器和事务实际上是关于 lifecyles（特别是 Transient 生命周期），在 ASP.NET 中，容器已经知道来解决每个请求。因此，您无需重复该工作。 StructureMap documentation 解释得比我好。

旁注：有一个 PreApplicationStart 属性可以放在程序集上，它指示在 Application_start 之前运行的方法，但因为它是一个静态方法，所以它实际上只适用于静态配置——而 IoC 容器则不行。

有什么方法可以在全局 asax 应用程序启动之前将 owin startup.cs 配置为运行吗？

Is there any way to configure owin startup.cs to be run before global asax application start?

c#

owin

asp.net-mvc-5

有什么方法可以在全局 asax 应用程序启动之前将 owin startup.cs 配置为 运行 吗？

Is there any way to configure owin startup.cs to be run before global asax application start?

c#

owin

asp.net-mvc-5

有什么方法可以在全局 asax 应用程序启动之前将 owin startup.cs 配置为运行吗？