Question

在使用异步主机实现（在我的情况下使用Tasks）并异步引发异常（即，从延续开始）的服务上调用标有“ TransactionScopeRequired = true”的WCF操作，似乎总是导致以下异常（不是我抛出的异常）在客户端上收到：

System.AggregateException: One or more errors occurred. ---> System.ServiceModel.ProtocolException: The transaction under which this method call was executing was asynchronously aborted.
   at System.ServiceModel.Channels.ServiceChannel.ThrowIfFaultUnderstood(Message reply, MessageFault fault, String action, MessageVersion version, FaultConverter faultConverter)
   at System.ServiceModel.Channels.ServiceChannel.HandleReply(ProxyOperationRuntime operation, ProxyRpc& rpc)
   at System.ServiceModel.Channels.ServiceChannel.EndCall(String action, Object[] outs, IAsyncResult result)
   at System.ServiceModel.Channels.ServiceChannelProxy.TaskCreator.<>c__DisplayClass6_0.<CreateTask>b__0(IAsyncResult asyncResult)
   at System.Threading.Tasks.TaskFactory`1.FromAsyncCoreLogic(IAsyncResult iar, Func`2 endFunction, Action`1 endAction, Task`1 promise, Boolean requiresSynchronization)
   --- End of inner exception stack trace ---
   at System.Threading.Tasks.Task.ThrowIfExceptional(Boolean includeTaskCanceledExceptions)
   at System.Threading.Tasks.Task.Wait(Int32 millisecondsTimeout, CancellationToken cancellationToken)
   at System.Threading.Tasks.Task.Wait()
   at WcfTransactionScopeRequiredAsync.Program.Main(String[] args) in D:\\WcfTransactionScopeRequiredAsync\\WcfTransactionScopeRequiredAsync.Client\\Program.cs:line 19
---> (Inner Exception #0) System.ServiceModel.ProtocolException: The transaction under which this method call was executing was asynchronously aborted.
   at System.ServiceModel.Channels.ServiceChannel.ThrowIfFaultUnderstood(Message reply, MessageFault fault, String action, MessageVersion version, FaultConverter faultConverter)
   at System.ServiceModel.Channels.ServiceChannel.HandleReply(ProxyOperationRuntime operation, ProxyRpc& rpc)
   at System.ServiceModel.Channels.ServiceChannel.EndCall(String action, Object[] outs, IAsyncResult result)
   at System.ServiceModel.Channels.ServiceChannelProxy.TaskCreator.<>c__DisplayClass6_0.<CreateTask>b__0(IAsyncResult asyncResult)
   at System.Threading.Tasks.TaskFactory`1.FromAsyncCoreLogic(IAsyncResult iar, Func`2 endFunction, Action`1 endAction, Task`1 promise, Boolean requiresSynchronization)<---

服务合同：

[ServiceContract]
public interface IService
{
    [FaultContract(typeof(SomeFault))]
    [TransactionFlow(TransactionFlowOption.Allowed)]
    [OperationContract]
    Task DoItAsync();
}

服务主机实施：

[OperationBehavior(TransactionScopeRequired = true)]
public async Task DoItAsync()
{
    using (TransactionScope tx = new TransactionScope(TransactionScopeOption.Required, TransactionScopeAsyncFlowOption.Enabled))
    {
        await Task.Delay(1000).ConfigureAwait(continueOnCapturedContext: false);
        throw new FaultException<SomeFault>(new SomeFault());
        tx.Complete();
    }
}

客户端是同步的：

service.DoItAsync().Wait();

在这种情况下，客户端不会流事务（因此，这绝对不是分布式事务（通过检查Transaction.Current.TransactionInformation.DistributedIdentifier进行验证）。

此代码已在.NET Framework 4.7.2中进行了测试。

到目前为止，我的研究表明，该ProtocolException是由WCF管道在服务主机上抛出的（从Exception中的堆栈跟踪中也可以看出），并且应该被认为可以处理在主机控制之外中止的分布式事务（即当DTC发布中止时。尽管这似乎有些道理，但这里显然不是这种情况。

在主机上仍使用异步实现时，有什么方法可以避免此ProtocolException？

WCF + TransactionScopeRequired +异步+引发错误=> ProtocolException“执行方法的事务被异步中止”

0 个答案: