Question

我正在使用Visual Studio 2012 Express开发代码第一个Web应用程序。

我在web.config中使用此连接字符串：

<add name="myContext" connectionString="Data Source=.;Integrated Security=True;Initial Catalog=cityKingMVC4" providerName="System.Data.SqlClient" />

我正在使用SimpleMembership。

我正在尝试从Filters / InitializeSimpleMembershipAttribute.cs中为1个管理员提供种子： ...

WebSecurity.InitializeDatabaseConnection("myContext", "Users", "UserId", "Email", autoCreateTables: true);

// A: Create Admin user
if (!WebSecurity.ConfirmAccount("admin@mydom.com"))
{
   WebSecurity.CreateUserAndAccount("admin@mydom.com", "password");
}

// B: Create admin role if not exist
if (!Roles.RoleExists("Administrator"))
{
   Roles.CreateRole("Administrator");
   Roles.AddUserToRole("admin@mydom.com", "Administrator");
}

如果我评论A＆amp; B它不会崩溃。如果我不这样做，我得到这个： “WebSecurity.InitializeDatabaseConnection”方法只能调用一次。

如果我在'WebSecurity.InitializeDatabaseConnection'上调试并设置断点 - 它只调用一次，并且没有其他代码在任何地方调用WebSecurity.InitializeDatabaseConnection。

如果我调试 - 它会在文件中较高的另一行崩溃（标准的SimpleAuthentication文件）： LazyInitializer.EnsureInitialized（ref _initializer，ref _isInitialized，ref _initializerLock）;

出现此错误：调用目标引发了异常。

堆栈追踪：

[InvalidOperationException: The "WebSecurity.InitializeDatabaseConnection" method can be called only once.]
   WebMatrix.WebData.WebSecurity.InitializeMembershipProvider(SimpleMembershipProvider simpleMembership, DatabaseConnectionInfo connect, String userTableName, String userIdColumn, String userNameColumn, Boolean createTables) +87978
   WebMatrix.WebData.WebSecurity.InitializeProviders(DatabaseConnectionInfo connect, String userTableName, String userIdColumn, String userNameColumn, Boolean autoCreateTables) +86
   myapPMVC4.Filters.SimpleMembershipInitializer..ctor() in c:\Users\name\Documents\Visual Studio 2012\Projects\myapPMVC4\myapPMVC4\Filters\InitializeSimpleMembershipAttribute.cs:43

[InvalidOperationException: The ASP.NET Simple Membership database could not be initialized. For more information, please see http://go.microsoft.com/fwlink/?LinkId=256588]
   myapPMVC4.Filters.SimpleMembershipInitializer..ctor() in c:\Users\name\Documents\Visual Studio 2012\Projects\myapPMVC4\myapPMVC4\Filters\InitializeSimpleMembershipAttribute.cs:88

[TargetInvocationException: Exception has been thrown by the target of an invocation.]
   System.RuntimeTypeHandle.CreateInstance(RuntimeType type, Boolean publicOnly, Boolean noCheck, Boolean& canBeCached, RuntimeMethodHandleInternal& ctor, Boolean& bNeedSecurityCheck) +0
   System.RuntimeType.CreateInstanceSlow(Boolean publicOnly, Boolean skipCheckThis, Boolean fillCache, StackCrawlMark& stackMark) +159
   System.RuntimeType.CreateInstanceDefaultCtor(Boolean publicOnly, Boolean skipCheckThis, Boolean fillCache, StackCrawlMark& stackMark) +256
   System.Activator.CreateInstance(Type type, Boolean nonPublic) +127
   System.Activator.CreateInstance(Type type) +11
   System.Threading.LazyHelpers`1.ActivatorFactorySelector() +72
   System.Threading.LazyInitializer.EnsureInitializedCore(T& target, Boolean& initialized, Object& syncLock, Func`1 valueFactory) +241
   System.Threading.LazyInitializer.EnsureInitialized(T& target, Boolean& initialized, Object& syncLock) +139
   myapPMVC4.Filters.InitializeSimpleMembershipAttribute.OnActionExecuting(ActionExecutingContext filterContext) in c:\Users\name\Documents\Visual Studio 2012\Projects\myapPMVC4\myapPMVC4\Filters\InitializeSimpleMembershipAttribute.cs:22
   System.Web.Mvc.Async.AsyncControllerActionInvoker.InvokeActionMethodFilterAsynchronously(IActionFilter filter, ActionExecutingContext preContext, Func`1 nextInChain) +145
   System.Web.Mvc.Async.AsyncControllerActionInvoker.InvokeActionMethodFilterAsynchronously(IActionFilter filter, ActionExecutingContext preContext, Func`1 nextInChain) +840201
   System.Web.Mvc.Async.<>c__DisplayClass37.<BeginInvokeActionMethodWithFilters>b__31(AsyncCallback asyncCallback, Object asyncState) +266
   System.Web.Mvc.Async.WrappedAsyncResult`1.Begin(AsyncCallback callback, Object state, Int32 timeout) +146
   System.Web.Mvc.Async.AsyncResultWrapper.Begin(AsyncCallback callback, Object state, BeginInvokeDelegate beginDelegate, EndInvokeDelegate`1 endDelegate, Object tag, Int32 timeout) +202
   System.Web.Mvc.Async.AsyncResultWrapper.Begin(AsyncCallback callback, Object state, BeginInvokeDelegate beginDelegate, EndInvokeDelegate`1 endDelegate, Object tag) +112
   System.Web.Mvc.Async.<>c__DisplayClass25.<BeginInvokeAction>b__1e(AsyncCallback asyncCallback, Object asyncState) +839055
   System.Web.Mvc.Async.WrappedAsyncResult`1.Begin(AsyncCallback callback, Object state, Int32 timeout) +146
   System.Web.Mvc.Async.AsyncResultWrapper.Begin(AsyncCallback callback, Object state, BeginInvokeDelegate beginDelegate, EndInvokeDelegate`1 endDelegate, Object tag, Int32 timeout) +166
   System.Web.Mvc.Async.AsyncResultWrapper.Begin(AsyncCallback callback, Object state, BeginInvokeDelegate beginDelegate, EndInvokeDelegate`1 endDelegate, Object tag) +27
   System.Web.Mvc.<>c__DisplayClass1d.<BeginExecuteCore>b__17(AsyncCallback asyncCallback, Object asyncState) +50
   System.Web.Mvc.Async.WrappedAsyncResult`1.Begin(AsyncCallback callback, Object state, Int32 timeout) +146
   System.Web.Mvc.Async.AsyncResultWrapper.Begin(AsyncCallback callback, Object state, BeginInvokeDelegate beginDelegate, EndInvokeDelegate`1 endDelegate, Object tag, Int32 timeout) +166
   System.Web.Mvc.Controller.BeginExecuteCore(AsyncCallback callback, Object state) +826145
   System.Web.Mvc.Async.WrappedAsyncResult`1.Begin(AsyncCallback callback, Object state, Int32 timeout) +146
   System.Web.Mvc.Async.AsyncResultWrapper.Begin(AsyncCallback callback, Object state, BeginInvokeDelegate beginDelegate, EndInvokeDelegate`1 endDelegate, Object tag, Int32 timeout) +166
   System.Web.Mvc.Async.AsyncResultWrapper.Begin(AsyncCallback callback, Object state, BeginInvokeDelegate beginDelegate, EndInvokeDelegate endDelegate, Object tag) +27
   System.Web.Mvc.Controller.BeginExecute(RequestContext requestContext, AsyncCallback callback, Object state) +401
   System.Web.Mvc.<>c__DisplayClass8.<BeginProcessRequest>b__2(AsyncCallback asyncCallback, Object asyncState) +786250
   System.Web.Mvc.Async.WrappedAsyncResult`1.Begin(AsyncCallback callback, Object state, Int32 timeout) +146
   System.Web.Mvc.Async.AsyncResultWrapper.Begin(AsyncCallback callback, Object state, BeginInvokeDelegate beginDelegate, EndInvokeDelegate`1 endDelegate, Object tag, Int32 timeout) +166
   System.Web.Mvc.Async.AsyncResultWrapper.Begin(AsyncCallback callback, Object state, BeginInvokeDelegate beginDelegate, EndInvokeDelegate endDelegate, Object tag) +27
   System.Web.Mvc.MvcHandler.BeginProcessRequest(HttpContextBase httpContext, AsyncCallback callback, Object state) +343
   System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +12550291
   System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +288

发生了什么事？

THX

using System;
using System.Data.Entity;
using System.Data.Entity.Infrastructure;
using System.Threading;
using System.Web.Mvc;
using WebMatrix.WebData;
using System.Web.Security;
using myapPMVC4.Models;

namespace myapPMVC4.Filters
{
    [AttributeUsage(AttributeTargets.Class | AttributeTargets.Method, AllowMultiple = false, Inherited = true)]
    public sealed class InitializeSimpleMembershipAttribute : ActionFilterAttribute
    {
        private static SimpleMembershipInitializer _initializer;
        private static object _initializerLock = new object();
        private static bool _isInitialized;

        public override void OnActionExecuting(ActionExecutingContext filterContext)
        {
           LazyInitializer.EnsureInitialized(ref _initializer, ref _isInitialized, ref _initializerLock);
        }

        private class SimpleMembershipInitializer
        { 
            public SimpleMembershipInitializer()
            {
                Database.SetInitializer<UsersContext>(null);

                try
                {
                    using (var context = new UsersContext())
                    {
                        if (!context.Database.Exists())
                        {
                            // Create the SimpleMembership database without Entity Framework migration schema
                            ((IObjectContextAdapter)context).ObjectContext.CreateDatabase();
                        }
                    }

                    //WebSecurity.InitializeDatabaseConnection("DefaultConnection", "UserProfile", "UserId", "UserName", autoCreateTables: true);

                    if (!WebSecurity.Initialized)
                    {
                       WebSecurity.InitializeDatabaseConnection("myapPMVC4DBContext", "Users", "UserId", "Email", autoCreateTables: true);
                    }


                    // Create Admin user
                    if (!WebSecurity.ConfirmAccount("admin@myapp.com"))
                    {
                       //WebSecurity.CreateUserAndAccount("admin", "pass", new { email = "a@b.com" });
                       WebSecurity.CreateUserAndAccount("admin@myapp.com", "pass");
                    }

                    // Create admin role if not exist
                    if (!Roles.RoleExists("Administrator"))
                    {
                       Roles.CreateRole("Administrator");
                       Roles.AddUserToRole("admin@myapp.com", "Administrator");
                    }


                }
                catch (Exception ex)
                {
                    throw new InvalidOperationException("The ASP.NET Simple Membership database could not be initialized. For more information, please see http://go.microsoft.com/fwlink/?LinkId=256588", ex);
                }
            }
        }
    }
}

Answer 1

问题......

是InitializeDatabaseConnection内部调用WebSecurity.InitializeProviders，此方法不是线程安全的，然后将此与WebSecurity通常需要从各个位置初始化的事实相结合。这具有影响，因为Web应用程序本身就是多线程环境......并且WebSecurity.Initialized和WebSecurity.InitializeDatabaseConnection 在一起使用时不是线程安全的 - 它们会创建典型的竞争条件。

种子设定（用于迁移）意味着您的WebSecurity可以多次初始化，因为您可能还需要在Global.asax.cs中对其进行初始化，以便在关闭种子的情况下部署您的InitializeSimpleMembershipAttribute可以通过实时部署等中的http请求同时多次调用

将初始化代码放在多个位置也会破坏您的DRY nss

解决方案......

确保您的init调用是线程安全的，并且每个AppDomain实例只发生一次。使用线程安全的单例类来执行此操作;并减少重复的代码。

根据您的应用，从以下任何/所有方法调用单身人士的EnsureInitialize方法：

Global.asax.cs（先前Application_Start方法）
Migrations \ Configuration.cs Seed方法（在创建用户之前）
过滤器\ InitializeSimpleMembershipAttribute.cs（初始化上下文后在SimpleMembershipInitializer构造函数中）

以下是一个简单的单例示例：

// Call this with WebSecurityInitializer.Instance.EnsureInitialize()
public class WebSecurityInitializer {
    private WebSecurityInitializer() { }
    public static readonly WebSecurityInitializer Instance = new WebSecurityInitializer();
    private bool isNotInit = true;
    private readonly object SyncRoot = new object();
    public void EnsureInitialize() {
        if (isNotInit) {
            lock (this.SyncRoot) {
                if (isNotInit) {
                    isNotInit = false;
                    WebSecurity.InitializeDatabaseConnection("MyContextName",
                        userTableName: "UserProfile", userIdColumn: "UserId", userNameColumn: "UserName",
                        autoCreateTables: true);
                }
            }
        }
    }
}

一旦我这样做了，我提到的错误案例就消失了，不再被人看到了。

脚注

单例类还会保留您的代码DRY，如果您需要稍后更改WebSecurity.InitializeDatabaseConnection的配置，这在早期阶段的应用程序开发中尤其有用，因为它只会在一个地方（结束）编辑）

我还保持SimpleMembershipInitializer干净，然后将我的用户与Migrations \ Configuration.cs Seed方法中的常用种子一起播种。通过将所有内容保存在一个位置，这有助于通过我的迁移实现播种的可测试性。我使用单元测试来确保我们总是可以在迁移树上上下移动，因此这样做更容易。

但是，您的种子代码的位置无关紧要，更重要的是确保您在全局范围内仅在AppDomain中初始化了一次WebSecurity，并且对InitializeDatabaseConnection的任何调用都是线程安全的。

Answer 2

将此代码添加到Global.asax.cs。这将确保您的数据库始终在任何其他执行之前初始化。还要确保在Application_Start()

中首次注册

if (!WebSecurity.Initialized)
                WebSecurity.InitializeDatabaseConnection("DefaultConnection",
"UserProfile", "UserId", "UserName", autoCreateTables: true);

摆脱Filters/InitializeSimpleMembershipAttribute.cs或只是评论里面的代码，以防你想回到它。

删除[InitializeSimpleMembership]

顶部的AccountController.cs

此外，如果您尚未启用迁移，我建议您这样做。这样，当您运行Configuration.cs

时，您可以在Migration folder内创建Enable-Migrations种子。

Answer 3

如果已经初始化，请确保第一次通话：

if (!WebSecurity.Initialized)
{
    // Do the initialization first.
}

// The rest of the code

这样您就可以确保不重复初始化过程。

Answer 4

您的AccountController类还有InitializeSimpleMembership属性吗？（这是默认值）。如果是这样，那么您正在初始化两次。

Answer 5

要确保WebSecurity.InitializeDatabaseConnection未被调用两次，只需使用WebSecurity.Initialized检查它是否已被调用。这blog post provides detailed instructions on seeding and customizing SimpleMembership。本博客中有一系列关于使用SimpleMembership的内容，我还建议您查看decoupling SimpleMembership from your ASP.NET MVC Application。您可以获得complete source code for these examples here。

ASP.NET MVC 4，“WebSecurity.InitializeDatabaseConnection”方法只能调用一次

5 个答案:

问题......

解决方案......