Question

即使我使用的是ConfigureAwait（false），我也会在某些C＃代码上遇到死锁。不幸的是，我无法全面使用异步，因此我依赖于ConfigureAwait。

情况是我需要发出HTTP请求，以便在启动Web应用程序和控制台应用程序期间从Azure AD检索数据库访问令牌。在这两种情况下，当Autofac尝试解析触发Web请求的数据库令牌时，程序会死锁。奇怪的是它可以工作两次但第三次失败。

Autofac模块：

 public class AzureActiveDirectoryModule : BaseModule
 {
    protected override bool SupportsMultipleModuleRegistrations => true;

    protected override void Load(ContainerBuilder builder)
    {
        builder.RegisterType<AzureActiveDirectoryService>().As<IAzureActiveDirectoryService>();

        builder.Register(c => c.Resolve<IAzureActiveDirectoryService>().GetAuthenticationContext())
               .As<AuthenticationContext>()
               .SingleInstance();

        builder.Register(c => c.Resolve<IAzureActiveDirectoryService>().GetCertificateCredential())
               .As<ClientAssertionCertificate>()
               .SingleInstance();

        builder.Register(c =>
                         c.Resolve<IAzureActiveDirectoryService>()
                          .GetDatabaseAccessToken(c.Resolve<AuthenticationContext>(), c.Resolve<ClientAssertionCertificate>()))
               .Named<string>(PersistenceModule.DatabaseAccessToken);
    }
}

发出HTTP请求的服务（我已通过调用google取代了http请求）：

public class AzureActiveDirectoryService : IAzureActiveDirectoryService
{

    public string GetDatabaseAccessToken(AuthenticationContext authContext, ClientAssertionCertificate certCred)
    {
        try
        {
            return AcquireDatabaseToken(certCred, authContext).Result;
        }
        catch (Exception ex)
        {
            Log.Error(ex, "Exception occurred while attempting to retrieve database access token.");
        }

        return string.Empty;
    }

    private async Task<string> AcquireDatabaseToken(ClientAssertionCertificate certCred, AuthenticationContext authContext)
    {
            try
            {
                await DoHttpRequestAsync().ConfigureAwait(false);
                return string.Empty;
            }
            catch (Exception ex)
            {
                Log.Error(ex,
                          "An error occurred",
                          ex.ToString());
            }
    }

    private async Task<string> DoHttpRequestAsync()
    {
        using (HttpClient client = new HttpClient())
        {
            client.DefaultRequestHeaders.Accept.Clear();
            HttpRequestMessage requestMessage = new HttpRequestMessage();
            requestMessage.RequestUri = new Uri("http://www.google.com");
            requestMessage.Headers.Accept.Clear();

            client.Timeout = TimeSpan.FromMilliseconds(30000);

            try
            {
                await client.SendAsync(requestMessage).ConfigureAwait(false);
            }
            catch (Exception ex)
            {
                var a = ex.Message;
            }

        }

        return string.Empty;
    }
}

这里是死锁线程的（编辑过的）堆栈跟踪（在控制台应用中） -

mscorlib.dll!System.Threading.Monitor.Wait(object obj, int millisecondsTimeout, bool exitContext)   Unknown
mscorlib.dll!System.Threading.Monitor.Wait(object obj, int millisecondsTimeout) Unknown
mscorlib.dll!System.Threading.ManualResetEventSlim.Wait(int millisecondsTimeout, System.Threading.CancellationToken cancellationToken)  Unknown
mscorlib.dll!System.Threading.Tasks.Task.SpinThenBlockingWait(int millisecondsTimeout, System.Threading.CancellationToken cancellationToken)    Unknown
mscorlib.dll!System.Threading.Tasks.Task.InternalWait(int millisecondsTimeout, System.Threading.CancellationToken cancellationToken)    Unknown
mscorlib.dll!System.Threading.Tasks.Task<string>.GetResultCore(bool waitCompletionNotification) Unknown
mscorlib.dll!System.Threading.Tasks.Task<System.__Canon>.Result.get()   Unknown Contoso.Infrastructure.dll!Infrastructure.Azure.AzureActiveDirectoryService.GetDatabaseAccessToken(Microsoft.IdentityModel.Clients.ActiveDirectory.AuthenticationContext authContext, Microsoft.IdentityModel.Clients.ActiveDirectory.ClientAssertionCertificate certCred) Line 101 C#
Contoso.Infrastructure.dll!Infrastructure.Modules.Azure.AzureActiveDirectoryModule.Load.AnonymousMethod__2_2(Autofac.IComponentContext c) Line 30   C#
Autofac.dll!Autofac.RegistrationExtensions.Register.AnonymousMethod__f(Autofac.IComponentContext c, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> p)   Unknown
Autofac.dll!Autofac.Builder.RegistrationBuilder.ForDelegate.AnonymousMethod__0(Autofac.IComponentContext c, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> p)   Unknown
Autofac.dll!Autofac.Core.Activators.Delegate.DelegateActivator.ActivateInstance(Autofac.IComponentContext context, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters)   Unknown
Autofac.dll!Autofac.Core.Resolving.InstanceLookup.Activate(System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters)   Unknown
Autofac.dll!Autofac.Core.Resolving.InstanceLookup.Execute() Unknown
Autofac.dll!Autofac.Core.Resolving.ResolveOperation.GetOrCreateInstance(Autofac.Core.ISharingLifetimeScope currentOperationScope, Autofac.Core.IComponentRegistration registration, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters)  Unknown
Autofac.dll!Autofac.Core.Resolving.InstanceLookup.ResolveComponent(Autofac.Core.IComponentRegistration registration, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters) Unknown
Autofac.dll!Autofac.ResolutionExtensions.TryResolveService(Autofac.IComponentContext context, Autofac.Core.Service service, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters, out object instance) Unknown
Autofac.dll!Autofac.ResolutionExtensions.ResolveService(Autofac.IComponentContext context, Autofac.Core.Service service, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters) Unknown
Autofac.dll!Autofac.ResolutionExtensions.ResolveNamed<string>(Autofac.IComponentContext context, string serviceName, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters) Unknown
Autofac.dll!Autofac.ResolutionExtensions.ResolveNamed<string>(Autofac.IComponentContext context, string serviceName)    Unknown
Contoso.Infrastructure.dll!Infrastructure.Modules.PersistenceModule.Load.AnonymousMethod__9_0(Autofac.IComponentContext c) Line 54  C#
Autofac.dll!Autofac.RegistrationExtensions.Register.AnonymousMethod__f(Autofac.IComponentContext c, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> p)   Unknown
Autofac.dll!Autofac.Builder.RegistrationBuilder.ForDelegate.AnonymousMethod__0(Autofac.IComponentContext c, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> p)   Unknown
Autofac.dll!Autofac.Core.Activators.Delegate.DelegateActivator.ActivateInstance(Autofac.IComponentContext context, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters)   Unknown
Autofac.dll!Autofac.Core.Resolving.InstanceLookup.Activate(System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters)   Unknown
Autofac.dll!Autofac.Core.Resolving.InstanceLookup.Execute() Unknown
Autofac.dll!Autofac.Core.Resolving.ResolveOperation.GetOrCreateInstance(Autofac.Core.ISharingLifetimeScope currentOperationScope, Autofac.Core.IComponentRegistration registration, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters)  Unknown
Autofac.dll!Autofac.Core.Resolving.InstanceLookup.ResolveComponent(Autofac.Core.IComponentRegistration registration, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters) Unknown
Autofac.dll!Autofac.ResolutionExtensions.TryResolveService(Autofac.IComponentContext context, Autofac.Core.Service service, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters, out object instance) Unknown
Autofac.dll!Autofac.ResolutionExtensions.ResolveService(Autofac.IComponentContext context, Autofac.Core.Service service, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters) Unknown
Autofac.dll!Autofac.ResolutionExtensions.Resolve<System.Data.Common.DbConnection>(Autofac.IComponentContext context, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters) Unknown
Autofac.dll!Autofac.ResolutionExtensions.Resolve<System.Data.Common.DbConnection>(Autofac.IComponentContext context)    Unknown
Contoso.Infrastructure.dll!Infrastructure.Modules.PersistenceModule.Load.AnonymousMethod__9_1(Autofac.IComponentContext c) Line 62  C#
Autofac.dll!Autofac.RegistrationExtensions.Register.AnonymousMethod__f(Autofac.IComponentContext c, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> p)   Unknown
Autofac.dll!Autofac.Builder.RegistrationBuilder.ForDelegate.AnonymousMethod__0(Autofac.IComponentContext c, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> p)   Unknown
Autofac.dll!Autofac.Core.Activators.Delegate.DelegateActivator.ActivateInstance(Autofac.IComponentContext context, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters)   Unknown
Autofac.dll!Autofac.Core.Resolving.InstanceLookup.Activate(System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters)   Unknown
Autofac.dll!Autofac.Core.Resolving.InstanceLookup.Execute.AnonymousMethod__0()  Unknown
Autofac.dll!Autofac.Core.Lifetime.LifetimeScope.GetOrCreateAndShare(System.Guid id, System.Func<object> creator)    Unknown
Autofac.dll!Autofac.Core.Resolving.InstanceLookup.Execute() Unknown
Autofac.dll!Autofac.Core.Resolving.ResolveOperation.GetOrCreateInstance(Autofac.Core.ISharingLifetimeScope currentOperationScope, Autofac.Core.IComponentRegistration registration, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters)  Unknown
Autofac.dll!Autofac.Core.Resolving.InstanceLookup.ResolveComponent(Autofac.Core.IComponentRegistration registration, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters) Unknown
Autofac.dll!Autofac.ResolutionExtensions.TryResolveService(Autofac.IComponentContext context, Autofac.Core.Service service, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters, out object instance) Unknown
Autofac.dll!Autofac.ResolutionExtensions.ResolveService(Autofac.IComponentContext context, Autofac.Core.Service service, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters) Unknown
Autofac.dll!Autofac.ResolutionExtensions.Resolve<Infrastructure.Persistence.IDbContext>(Autofac.IComponentContext context, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters)   Unknown
Autofac.dll!Autofac.ResolutionExtensions.Resolve<Infrastructure.Persistence.IDbContext>(Autofac.IComponentContext context)  Unknown
Contoso.Infrastructure.dll!Infrastructure.Modules.PersistenceModule.Load.AnonymousMethod__9_2(Autofac.IComponentContext c) Line 68  C#
Autofac.dll!Autofac.RegistrationExtensions.Register.AnonymousMethod__f(Autofac.IComponentContext c, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> p)   Unknown
Autofac.dll!Autofac.Builder.RegistrationBuilder.ForDelegate.AnonymousMethod__0(Autofac.IComponentContext c, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> p)   Unknown
Autofac.dll!Autofac.Core.Activators.Delegate.DelegateActivator.ActivateInstance(Autofac.IComponentContext context, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters)   Unknown
Autofac.dll!Autofac.Core.Resolving.InstanceLookup.Activate(System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters)   Unknown
Autofac.dll!Autofac.Core.Resolving.InstanceLookup.Execute.AnonymousMethod__0()  Unknown
Autofac.dll!Autofac.Core.Lifetime.LifetimeScope.GetOrCreateAndShare(System.Guid id, System.Func<object> creator)    Unknown
Autofac.dll!Autofac.Core.Resolving.InstanceLookup.Execute() Unknown
Autofac.dll!Autofac.Core.Resolving.ResolveOperation.GetOrCreateInstance(Autofac.Core.ISharingLifetimeScope currentOperationScope, Autofac.Core.IComponentRegistration registration, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters)  Unknown
Autofac.dll!Autofac.Core.Resolving.InstanceLookup.ResolveComponent(Autofac.Core.IComponentRegistration registration, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters) Unknown
Autofac.dll!Autofac.Core.Activators.Reflection.AutowiringParameter.CanSupplyValue.AnonymousMethod__0()  Unknown
Autofac.dll!Autofac.Core.Activators.Reflection.ConstructorParameterBinding.Instantiate()    Unknown
Autofac.dll!Autofac.Core.Activators.Reflection.ReflectionActivator.ActivateInstance(Autofac.IComponentContext context, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters)   Unknown
Autofac.dll!Autofac.Core.Resolving.InstanceLookup.Activate(System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters)   Unknown
Autofac.dll!Autofac.Core.Resolving.InstanceLookup.Execute.AnonymousMethod__0()  Unknown
Autofac.dll!Autofac.Core.Lifetime.LifetimeScope.GetOrCreateAndShare(System.Guid id, System.Func<object> creator)    Unknown
Autofac.dll!Autofac.Core.Resolving.InstanceLookup.Execute() Unknown
Autofac.dll!Autofac.Core.Resolving.ResolveOperation.GetOrCreateInstance(Autofac.Core.ISharingLifetimeScope currentOperationScope, Autofac.Core.IComponentRegistration registration, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters)  Unknown
Autofac.dll!Autofac.Core.Resolving.InstanceLookup.ResolveComponent(Autofac.Core.IComponentRegistration registration, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters) Unknown
Autofac.dll!Autofac.Features.Collections.CollectionRegistrationSource.RegistrationsFor.AnonymousMethod__1(Autofac.Core.IComponentRegistration cr)   Unknown
System.Core.dll!System.Linq.Enumerable.WhereSelectArrayIterator<System.__Canon, System.__Canon>.MoveNext()  Unknown
System.Core.dll!System.Linq.Buffer<object>.Buffer(System.Collections.Generic.IEnumerable<object> source)    Unknown
System.Core.dll!System.Linq.Enumerable.ToArray<object>(System.Collections.Generic.IEnumerable<object> source)   Unknown
Autofac.dll!Autofac.Features.Collections.CollectionRegistrationSource.RegistrationsFor.AnonymousMethod__0(Autofac.IComponentContext c, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> p)    Unknown
Autofac.dll!Autofac.Core.Activators.Delegate.DelegateActivator.ActivateInstance(Autofac.IComponentContext context, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters)   Unknown
Autofac.dll!Autofac.Core.Resolving.InstanceLookup.Activate(System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters)   Unknown
Autofac.dll!Autofac.Core.Resolving.InstanceLookup.Execute() Unknown
Autofac.dll!Autofac.Core.Resolving.ResolveOperation.GetOrCreateInstance(Autofac.Core.ISharingLifetimeScope currentOperationScope, Autofac.Core.IComponentRegistration registration, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters)  Unknown
Autofac.dll!Autofac.Core.Resolving.InstanceLookup.ResolveComponent(Autofac.Core.IComponentRegistration registration, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters) Unknown
Autofac.dll!Autofac.ResolutionExtensions.TryResolveService(Autofac.IComponentContext context, Autofac.Core.Service service, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters, out object instance) Unknown
Autofac.dll!Autofac.ResolutionExtensions.ResolveService(Autofac.IComponentContext context, Autofac.Core.Service service, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters) Unknown
Autofac.dll!Autofac.ResolutionExtensions.Resolve<System.Collections.Generic.IEnumerable<Dispatching.Core.Tasks.Core.ITasksConfigurationSet>>(Autofac.IComponentContext context, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters)  Unknown
Autofac.dll!Autofac.ResolutionExtensions.Resolve<System.Collections.Generic.IEnumerable<Dispatching.Core.Tasks.Core.ITasksConfigurationSet>>(Autofac.IComponentContext context) Unknown
Contoso.Dispatching.Core.dll!Dispatching.Core.Modules.TaskRunnersModule.Load.AnonymousMethod__2_0(Autofac.IComponentContext c) Line 39  C#
Autofac.dll!Autofac.RegistrationExtensions.Register.AnonymousMethod__f(Autofac.IComponentContext c, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> p)   Unknown
Autofac.dll!Autofac.Builder.RegistrationBuilder.ForDelegate.AnonymousMethod__0(Autofac.IComponentContext c, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> p)   Unknown
Autofac.dll!Autofac.Core.Activators.Delegate.DelegateActivator.ActivateInstance(Autofac.IComponentContext context, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters)   Unknown
Autofac.dll!Autofac.Core.Resolving.InstanceLookup.Activate(System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters)   Unknown
Autofac.dll!Autofac.Core.Resolving.InstanceLookup.Execute.AnonymousMethod__0()  Unknown
Autofac.dll!Autofac.Core.Lifetime.LifetimeScope.GetOrCreateAndShare(System.Guid id, System.Func<object> creator)    Unknown
Autofac.dll!Autofac.Core.Resolving.InstanceLookup.Execute() Unknown
Autofac.dll!Autofac.Core.Resolving.ResolveOperation.GetOrCreateInstance(Autofac.Core.ISharingLifetimeScope currentOperationScope, Autofac.Core.IComponentRegistration registration, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters)  Unknown
Autofac.dll!Autofac.Core.Resolving.InstanceLookup.ResolveComponent(Autofac.Core.IComponentRegistration registration, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters) Unknown
Autofac.dll!Autofac.Core.Activators.Reflection.AutowiringParameter.CanSupplyValue.AnonymousMethod__0()  Unknown
Autofac.dll!Autofac.Core.Activators.Reflection.ConstructorParameterBinding.Instantiate()    Unknown
Autofac.dll!Autofac.Core.Activators.Reflection.ReflectionActivator.ActivateInstance(Autofac.IComponentContext context, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters)   Unknown
Autofac.dll!Autofac.Core.Resolving.InstanceLookup.Activate(System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters)   Unknown
Autofac.dll!Autofac.Core.Resolving.InstanceLookup.Execute.AnonymousMethod__0()  Unknown
Autofac.dll!Autofac.Core.Lifetime.LifetimeScope.GetOrCreateAndShare(System.Guid id, System.Func<object> creator)    Unknown
Autofac.dll!Autofac.Core.Resolving.InstanceLookup.Execute() Unknown
Autofac.dll!Autofac.Core.Resolving.ResolveOperation.GetOrCreateInstance(Autofac.Core.ISharingLifetimeScope currentOperationScope, Autofac.Core.IComponentRegistration registration, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters)  Unknown
Autofac.dll!Autofac.Core.Resolving.InstanceLookup.ResolveComponent(Autofac.Core.IComponentRegistration registration, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters) Unknown
Autofac.dll!Autofac.ResolutionExtensions.TryResolveService(Autofac.IComponentContext context, Autofac.Core.Service service, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters, out object instance) Unknown
Autofac.dll!Autofac.ResolutionExtensions.ResolveService(Autofac.IComponentContext context, Autofac.Core.Service service, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters) Unknown
Autofac.dll!Autofac.ResolutionExtensions.Resolve<Dispatching.Core.Tasks.Core.ITaskManager>(Autofac.IComponentContext context, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters)    Unknown
Autofac.dll!Autofac.ResolutionExtensions.Resolve<Dispatching.Core.Tasks.Core.ITaskManager>(Autofac.IComponentContext context)   Unknown
Contoso.Dispatching.Core.dll!Dispatching.Core.Modules.DispatchingModule.Load.AnonymousMethod__2_2(Autofac.IComponentContext c) Line 73  C#
Autofac.dll!Autofac.RegistrationExtensions.Register.AnonymousMethod__f(Autofac.IComponentContext c, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> p)   Unknown
Autofac.dll!Autofac.Builder.RegistrationBuilder.ForDelegate.AnonymousMethod__0(Autofac.IComponentContext c, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> p)   Unknown
Autofac.dll!Autofac.Core.Activators.Delegate.DelegateActivator.ActivateInstance(Autofac.IComponentContext context, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters)   Unknown
Autofac.dll!Autofac.Core.Resolving.InstanceLookup.Activate(System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters)   Unknown
Autofac.dll!Autofac.Core.Resolving.InstanceLookup.Execute() Unknown
Autofac.dll!Autofac.Core.Resolving.ResolveOperation.GetOrCreateInstance(Autofac.Core.ISharingLifetimeScope currentOperationScope, Autofac.Core.IComponentRegistration registration, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters)  Unknown
Autofac.dll!Autofac.Core.Resolving.ResolveOperation.Execute(Autofac.Core.IComponentRegistration registration, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters)    Unknown
Autofac.dll!Autofac.Core.Lifetime.LifetimeScope.ResolveComponent(Autofac.Core.IComponentRegistration registration, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters)   Unknown
Autofac.dll!Autofac.Core.Container.ResolveComponent(Autofac.Core.IComponentRegistration registration, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters)    Unknown
Autofac.dll!Autofac.ResolutionExtensions.TryResolveService(Autofac.IComponentContext context, Autofac.Core.Service service, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters, out object instance) Unknown
Autofac.dll!Autofac.ResolutionExtensions.ResolveService(Autofac.IComponentContext context, Autofac.Core.Service service, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters) Unknown
Autofac.dll!Autofac.ResolutionExtensions.Resolve<Dispatching.Core.Worker.DispatcherWorker>(Autofac.IComponentContext context, System.Collections.Generic.IEnumerable<Autofac.Core.Parameter> parameters)    Unknown
Autofac.dll!Autofac.ResolutionExtensions.Resolve<Dispatching.Core.Worker.DispatcherWorker>(Autofac.IComponentContext context)   Unknown
Topshelf.Autofac.dll!Topshelf.Autofac.ServiceConfiguratorExtensions.ConstructUsingAutofacContainer.AnonymousMethod__0_0(Topshelf.Runtime.HostSettings serviceFactory)   Unknown
Topshelf.dll!Topshelf.Builders.DelegateServiceBuilder<Dispatching.Core.Worker.DispatcherWorker>.Build(Topshelf.Runtime.HostSettings settings)   Unknown
Topshelf.dll!Topshelf.Builders.RunBuilder.Build(Topshelf.Builders.ServiceBuilder serviceBuilder)    Unknown
Topshelf.dll!Topshelf.HostConfigurators.HostConfiguratorImpl.CreateHost()   Unknown
Topshelf.dll!Topshelf.HostFactory.New(System.Action<Topshelf.HostConfigurators.HostConfigurator> configureCallback) Unknown
Contoso.Dispatcher.Shell.exe!Dispatcher.Shell.Program.Main() Line 48    C#
[Native to Managed Transition]  
[Managed to Native Transition]  
mscorlib.dll!System.AppDomain.ExecuteAssembly(string assemblyFile, System.Security.Policy.Evidence assemblySecurity, string[] args) Unknown
Microsoft.VisualStudio.HostingProcess.Utilities.dll!Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly()   Unknown
mscorlib.dll!System.Threading.ThreadHelper.ThreadStart_Context(object state)    Unknown
mscorlib.dll!System.Threading.ExecutionContext.RunInternal(System.Threading.ExecutionContext executionContext, System.Threading.ContextCallback callback, object state, bool preserveSyncCtx)   Unknown
mscorlib.dll!System.Threading.ExecutionContext.Run(System.Threading.ExecutionContext executionContext, System.Threading.ContextCallback callback, object state, bool preserveSyncCtx)   Unknown
mscorlib.dll!System.Threading.ExecutionContext.Run(System.Threading.ExecutionContext executionContext, System.Threading.ContextCallback callback, object state) Unknown
mscorlib.dll!System.Threading.ThreadHelper.ThreadStart()    Unknown

编辑：也许它不是一个僵局 - 似乎它冻结了所有线程。这是其他线程堆栈的顶部 -

mscorlib.dll!System.Threading.LazyInitializer.EnsureInitializedCore<System.__Canon>(ref System.__Canon target, ref bool initialized, ref object syncLock, System.Func<System.__Canon> valueFactory) Unknown
mscorlib.dll!System.Threading.LazyInitializer.EnsureInitialized<Infrastructure.Persistence.Migrator.FluentMigratorSchemaVersion.MigrationsInfo>(ref Infrastructure.Persistence.Migrator.FluentMigratorSchemaVersion.MigrationsInfo target, ref bool initialized, ref object syncLock, System.Func<Infrastructure.Persistence.Migrator.FluentMigratorSchemaVersion.MigrationsInfo> valueFactory) Unknown
Contoso.Infrastructure.dll!Infrastructure.Persistence.Migrator.FluentMigratorSchemaVersion.EnsureInitialized() Line 43  C#


mscorlib.dll!System.Threading.WaitHandle.InternalWaitOne(System.Runtime.InteropServices.SafeHandle waitableSafeHandle, long millisecondsTimeout, bool hasThreadAffinity, bool exitContext)  Unknown
mscorlib.dll!System.Threading.WaitHandle.WaitOne(System.TimeSpan timeout, bool exitContext) Unknown
mscorlib.dll!System.Threading.WaitHandle.WaitOne(System.TimeSpan timeout)   Unknown
Microsoft.ApplicationInsights.dll!Microsoft.ApplicationInsights.Channel.InMemoryTransmitter.Runner()    Unknown


mscorlib.dll!System.Threading.WaitHandle.InternalWaitOne(System.Runtime.InteropServices.SafeHandle waitableSafeHandle, long millisecondsTimeout, bool hasThreadAffinity, bool exitContext)  Unknown
mscorlib.dll!System.Threading.WaitHandle.WaitOne(int millisecondsTimeout, bool exitContext) Unknown
mscorlib.dll!System.Threading.WaitHandle.WaitOne()  Unknown
Microsoft.ServiceBus.dll!Microsoft.ServiceBus.Common.AsyncResult.End<Microsoft.ServiceBus.Messaging.ServiceBusResourceOperations.GetAsyncResult<Microsoft.ServiceBus.Messaging.TopicDescription>>(System.IAsyncResult result)   Unknown
Microsoft.ServiceBus.dll!Microsoft.ServiceBus.Common.AsyncResult<Microsoft.ServiceBus.Messaging.ServiceBusResourceOperations.GetAsyncResult<Microsoft.ServiceBus.Messaging.TopicDescription>>.End(System.IAsyncResult asyncResult)  Unknown
Microsoft.ServiceBus.dll!Microsoft.ServiceBus.Messaging.ServiceBusResourceOperations.EndGet<Microsoft.ServiceBus.Messaging.TopicDescription>(System.IAsyncResult asyncResult)   Unknown
Microsoft.ServiceBus.dll!Microsoft.ServiceBus.NamespaceManager.EndTopicExists(System.IAsyncResult result)   Unknown
Microsoft.ServiceBus.dll!Microsoft.ServiceBus.NamespaceManager.TopicExists(string path) Unknown
Contoso.Infrastructure.dll!Infrastructure.Azure.ServiceBus.ServiceBusTopic.Setup() Line 136 C#

Answer 1

如果你不能让它一直异步，那么让它一直同步：

public class AzureActiveDirectoryService : IAzureActiveDirectoryService
{
    public string GetDatabaseAccessToken(AuthenticationContext authContext, ClientAssertionCertificate certCred)
    {
        try
        {
            return AcquireDatabaseToken(certCred, authContext);
        }
        catch (Exception ex)
        {
            Log.Error(ex, "Exception occurred while attempting to retrieve database access token.");
        }

        return string.Empty;
    }

    private string AcquireDatabaseToken(ClientAssertionCertificate certCred, AuthenticationContext authContext)
    {
        try
        {
            DoHttpRequest();
            return string.Empty;
        }
        catch (Exception ex)
        {
            Log.Error(ex,
                      "An error occurred",
                      ex.ToString());
        }
    }

    private string DoHttpRequest()
    {
        using (WebClient client = new WebClient())
        {
            return client.DownloadString("http://www.google.com");
        }
        return string.Empty;
    }
}

Answer 2

解决方法是

return AcquireDatabaseToken(certCred,authContext).ConfigureAwait(false).GetAwaiter().GetResult();

而不是

return AcquireDatabaseToken(certCred,authContext).Result;

使用Autofac解析对象时，即使使用ConfigurationAwait（false）也会在Async上死锁

2 个答案: