NuGet库和EntityFramework抛出无法打开提供程序错误

Question

我们这里有个奇怪的情况。我们已经设置了NuGet图库的本地安装(与支持http://Nuget.org的代码相同)。IIS和DB在同一个机器上。IIS应用程序池已配置为在域用户下运行，该域用户也是计算机上的本地管理员，并且具有“作为服务登录的权限”权限。现在，当有人(在成功登录后)尝试上传包时，上传包业务需要花费很长时间，最终会抛出“基础提供程序无法打开”错误

  [TimeoutException: Transaction Timeout]

[TransactionException: The operation is not valid for the state of the transaction.]
   System.Transactions.TransactionState.EnlistPromotableSinglePhase(InternalTransaction tx, IPromotableSinglePhaseNotification promotableSinglePhaseNotification, Transaction atomicTransaction) +53
   System.Transactions.Transaction.EnlistPromotableSinglePhase(IPromotableSinglePhaseNotification promotableSinglePhaseNotification) +241
   System.Data.SqlClient.SqlInternalConnection.EnlistNonNull(Transaction tx) +273
   System.Data.ProviderBase.DbConnectionInternal.ActivateConnection(Transaction transaction) +150
   System.Data.ProviderBase.DbConnectionPool.GetConnection(DbConnection owningObject) +2647
   System.Data.ProviderBase.DbConnectionFactory.GetConnection(DbConnection owningConnection) +89
   System.Data.ProviderBase.DbConnectionClosed.OpenConnection(DbConnection outerConnection, DbConnectionFactory connectionFactory) +6372062
   System.Data.SqlClient.SqlConnection.Open() +300
   System.Data.EntityClient.EntityConnection.OpenStoreConnectionIf(Boolean openCondition, DbConnection storeConnectionToOpen, DbConnection originalConnection, String exceptionCode, String attemptedOperation, Boolean& closeStoreConnectionOnFailure) +67

[EntityException: The underlying provider failed on Open.]
   System.Data.EntityClient.EntityConnection.OpenStoreConnectionIf(Boolean openCondition, DbConnection storeConnectionToOpen, DbConnection originalConnection, String exceptionCode, String attemptedOperation, Boolean& closeStoreConnectionOnFailure) +11109230
   System.Data.EntityClient.EntityConnection.Open() +142
   System.Data.Objects.ObjectContext.EnsureConnection() +97
   System.Data.Objects.ObjectContext.ExecuteStoreQueryInternal(String commandText, String entitySetName, MergeOption mergeOption, Object[] parameters) +109
   System.Data.Objects.ObjectContext.ExecuteStoreQuery(String commandText, Object[] parameters) +87
   System.Data.Entity.Internal.InternalContext.ExecuteSqlQuery(String sql, Object[] parameters) +118
   System.Data.Entity.Internal.InternalContext.ExecuteSqlQueryAsIEnumerable(String sql, Object[] parameters) +85
   System.Data.Entity.Internal.InternalContext.ExecuteSqlQuery(Type elementType, String sql, Object[] parameters) +241
   System.Data.Entity.Internal.InternalSqlNonSetQuery.GetEnumerator() +34
   System.Data.Entity.Internal.InternalSqlQuery`1.GetEnumerator() +28
   System.Collections.Generic.List`1..ctor(IEnumerable`1 collection) +382
   System.Linq.Enumerable.ToList(IEnumerable`1 source) +80
   NuGetGallery.LuceneIndexingService.GetPackages(DbContext context, Nullable`1 dateTime) in C:\Source\DotNetDevEng.CitiNuGet\Gallery\DEV\Website\Infrastructure\Lucene\LuceneIndexingService.cs:55
   NuGetGallery.LuceneIndexingService.UpdateIndex() in C:\Source\DotNetDevEng.CitiNuGet\Gallery\DEV\Website\Infrastructure\Lucene\LuceneIndexingService.cs:32
   NuGetGallery.PackageService.CreatePackage(IPackage nugetPackage, User currentUser) in C:\Source\DotNetDevEng.CitiNuGet\Gallery\DEV\Website\Services\PackageService.cs:61
   NuGetGallery.PackagesController.VerifyPackage(Nullable`1 listed) in C:\Source\DotNetDevEng.CitiNuGet\Gallery\DEV\Website\Controllers\PackagesController.cs:503
   lambda_method(Closure , ControllerBase , Object[] ) +121
   System.Web.Mvc.ReflectedActionDescriptor.Execute(ControllerContext controllerContext, IDictionary`2 parameters) +248
   System.Web.Mvc.ControllerActionInvoker.InvokeActionMethod(ControllerContext controllerContext, ActionDescriptor actionDescriptor, IDictionary`2 parameters) +39
   System.Web.Mvc.<>c__DisplayClass15.<InvokeActionMethodWithFilters>b__12() +125
   System.Web.Mvc.ControllerActionInvoker.InvokeActionMethodFilter(IActionFilter filter, ActionExecutingContext preContext, Func`1 continuation) +640
   System.Web.Mvc.ControllerActionInvoker.InvokeActionMethodFilter(IActionFilter filter, ActionExecutingContext preContext, Func`1 continuation) +640
   System.Web.Mvc.ControllerActionInvoker.InvokeActionMethodWithFilters(ControllerContext controllerContext, IList`1 filters, ActionDescriptor actionDescriptor, IDictionary`2 parameters) +312
   System.Web.Mvc.ControllerActionInvoker.InvokeAction(ControllerContext controllerContext, String actionName) +691
   System.Web.Mvc.Controller.ExecuteCore() +162
   System.Web.Mvc.ControllerBase.Execute(RequestContext requestContext) +305
   System.Web.Mvc.<>c__DisplayClassb.<BeginProcessRequest>b__5() +62
   System.Web.Mvc.Async.<>c__DisplayClass1.<MakeVoidDelegate>b__0() +20
   System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +469
   System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +375

有趣的是，如果我将IIS应用程序池切换到在内置的"LocalSystem“帐户下运行，所有这些问题都会消失。我们要使用的域用户已临时设置为NuGetGallery数据库的数据库所有者，但这无济于事。

有没有人能建议我们这里可能缺少什么设置/配置？

Answer 1

这是由于代码中正在进行的环境事务造成的。代码依赖于TransactionScope类来管理各种事务，这些事务在嵌套时会出现拥塞。如果有人试图上传超过10MB大小的包，事情就会变得特别糟糕。一旦我们调整了盒子上的MSDTC，应用程序就开始稍微正常地运行。然而，它仍然间歇性地在它自己的事务中发生死锁，所以现在我们决定从包上传位中删除事务。

对于其他遇到这个问题的人，我会推荐这两个中的任何一个

1. 注释掉

中对TransactionScope的任何引用

Services\PackageService.cs (方法CreatePackage，第48行)

  using (var tx = new TransactionScope())
            {
                using (var stream = nugetPackage.GetStream())
                {
                    UpdateIsLatest(packageRegistration);
                    packageRegistrationRepo.CommitChanges();
                    packageFileSvc.SavePackageFile(package, stream);
                    tx.Complete();
                }
            }

在Controller\PackageController.cs方法中，VerifyPackage(bool？列出)行501

 using (var tx = new TransactionScope())
            {

                package = packageSvc.CreatePackage(nugetPackage, currentUser);
                packageSvc.PublishPackage(package.PackageRegistration.Id, package.Version);
                if (listed.HasValue && listed.Value == false)
                    packageSvc.MarkPackageUnlisted(package);
                uploadFileSvc.DeleteUploadFile(currentUser.Key);
                tx.Complete();
            }

2取消对这些行的注释，并遵循这里提到的方法http://blogs.msdn.com/b/dbrowne/archive/2010/05/21/using-new-transactionscope-considered-harmful.aspx

基本上创建一个事务作用域，它可以很好地与SQL Server一起工作。在InfraStructureFolder中创建一个新类，将其命名为TranscationUtils，并将代码复制到其中。则using块将如下所示

using (var tx = new TransactionUtils.CreateTransactionScope()){

//cod here
tx.Complete();
}

然而，第二种方法可能会导致另一个服务器错误，这也与您可以为TransactionScope指定的默认超时有关。我们个人决定采用方法1，并暂时注释掉所有TransactionScope引用。