Sending NServiceBus message inside TransactionScope

Question

I am trying to use NHibernate to save to a database in the same transaction as sending a message on the bus from inside an MVC application:

public void DoSomethingToEntity(Guid id)
{
    var session = _sessionFactory.OpenSession();
    CurrentSessionContext.Bind(session);

    using (var transactionScope = new TransactionScope())
    {
        var myEntity = _session.Get(id);
        myEntity.DoSomething();
        _session.Save(myEntity);
        _bus.Send(myMessage);
        transactionScope.Complete();
    }

    session.Dispose();
}

In the configuration, .MsmqTransport() is set with .IsTransactional(true).

If I do this inside a message handler (which is wrapped in its own transaction so does not need the TransactionScope) Then it all works as expected, and if I include an exception, both fail.

However, if I do it inside my own transaction in an MVC application, I get the following error after transactionScope.Complete() when leaving the using block.:

'The operation is not valid for the current state of the enlistment.'

Stack Trace: at System.Transactions.EnlistmentState.InternalIndoubt(InternalEnlistment enlistment) at System.Transactions.VolatileDemultiplexer.BroadcastInDoubt(VolatileEnlistmentSet& volatiles) at System.Transactions.TransactionStatePromotedIndoubt.EnterState(InternalTransaction tx) at System.Transactions.TransactionStatePromotedBase.InDoubtFromEnlistment(InternalTransaction tx) at System.Transactions.DurableEnlistmentDelegated.InDoubt(InternalEnlistment enlistment, Exception e) at System.Transactions.SinglePhaseEnlistment.InDoubt(Exception e) at System.Data.SqlClient.SqlDelegatedTransaction.SinglePhaseCommit(SinglePhaseEnlistment enlistment) at System.Transactions.TransactionStateDelegatedCommitting.EnterState(InternalTransaction tx) at System.Transactions.TransactionStateDelegated.BeginCommit(InternalTransaction tx, Boolean asyncCommit, AsyncCallback asyncCallback, Object asyncState) at System.Transactions.CommittableTransaction.Commit() at System.Transactions.TransactionScope.InternalDispose() at System.Transactions.TransactionScope.Dispose() at HumanResources.Application.Implementations.HolidayService.Book(BookHolidayRequest request) in C:\Users\paul.davies\Documents\GitHub\EdaCalendarExample\HumanResources.Application\Implementations\HolidayService.cs:line 76 at HumanResources.UI.Controllers.HolidayController.BookUpdate(BookHolidayViewModel viewModel) in C:\Users\paul.davies\Documents\GitHub\EdaCalendarExample\HumanResources.UI\Controllers\HolidayController.cs:line 82 at lambda_method(Closure , ControllerBase , Object[] ) at System.Web.Mvc.ActionMethodDispatcher.Execute(ControllerBase controller, Object[] parameters) at System.Web.Mvc.ReflectedActionDescriptor.Execute(ControllerContext controllerContext, IDictionary2 parameters) at System.Web.Mvc.ControllerActionInvoker.InvokeActionMethod(ControllerContext controllerContext, ActionDescriptor actionDescriptor, IDictionary2 parameters) at System.Web.Mvc.ControllerActionInvoker.<>c_DisplayClass15.b_12() at System.Web.Mvc.ControllerActionInvoker.InvokeActionMethodFilter(IActionFilter filter, ActionExecutingContext preContext, Func`1 continuation)

Latest Edit:

This code works:

public void DoSomethingToEntity(Guid id)
{
    var session = _sessionFactory.OpenSession();
    CurrentSessionContext.Bind(session);

    using (var transactionScope = new TransactionScope())
    {
        var myEntity = _session.Get(id);
        _bus.Send(myMessage);
        transactionScope.Complete();
    }

    session.Dispose();
}

This code creates the error:

public void DoSomethingToEntity(Guid id)
{
    var session = _sessionFactory.OpenSession();
    CurrentSessionContext.Bind(session);

    using (var transactionScope = new TransactionScope())
    {
        var myEntity = _session.Get(id);
        myEntity.AnyField = "a new value";
        _bus.Send(myMessage);
        transactionScope.Complete();
    }

    session.Dispose();
}

Note that I am not saving th entity in either example. The difference is in the second example, I am modifying the entity I have got from NHibernate. This is 100% reproducable.

Would it be possible to send the message first from the web app and then have NSB do the DB update and any other subsequent Sends()? — Adam Fyles
@AdamFyles This would be possible and would work but incurs a performance overhead which I'm sure could be avoided. I know using TransactionScope is possible but I can't get past this error. — Paul T Davies
To whoever downvoted: it is not helpful to me or other Stack Overflow users to downvote without an explanation why. — Paul T Davies
It seems like the EX happens when the sql driver tried to upgrade the TX to a distributed transaction (since the msmq send will force the upgrade). The reason that it works when running on a handler is that NSB has already received from msmq so the TX is already a distributed TX when the sql driver enlists. No idea why it happens though — Andreas Öhlund
This may not be related but you still have to call _session.Flush() before committing a TransactionScope even if the session flush mode is set to Commit - that only works for NH provided transactions. — eulerfx

eulerfx eulerfx · Accepted Answer · 2012-09-21T14:17:04

This may not be related but you still have to call _session.Flush() before committing a TransactionScope even if the session flush mode is set to Commit - that only works for NH provided transactions.

Sending NServiceBus message inside TransactionScope

2 Answers