Question

I have services been called through the ‘Guardian’ method, that has TransactionScope opened for each request and complete that transaction if everything is fine:

void ExecuteWorker(...)
{
    using (TransactionScope scope = new TransactionScope(TransactionScopeOption.RequiresNew))
    {
        ...CallLogicMethods...

        scope.Complete();
    }
}

One of the methods interacts with ‘External’ service, and in case if that interaction fails all my transaction fails also. As a result, I don’t save required data (been calculated before request to external service.

void DoLogic1(...)
{
    CalculateSomeData(...);
    SaveCalculatedData(...);

    DoRequestToExternalService(...);
}

What is the best way to resolve that issue?

Application is written using C#, .NET 4.0, MS SQL 2008.

Myself I see two solutions

1. Using try/catch:

   void DoLogic11(…)
   {
   CalculateSomeData(…);
   SaveCalculatedData(…);

   try
   {
       DoRequestToExternalService(...);
   }
   catch(Exception exc)
   {
       LogError(...);
   }
   

   }

The lack of this approach is that I’m hiding exception from the caller. But I would like to pass error outside as an exception (to be logged, etc).

1. Using ‘Nested transcation’, but I not sure how that works.

Here is my vision it should be:

void DoLogic12(...)
{
    using (TransactionScope scopeNested = new TransactionScope(TransactionScopeOption.Suppress))
    {
        CalculateSomeData(...);
        SaveCalculatedData(...);
        scopeNested.Complete()
    }

    DoRequestToExternalService(...);        
}

I’ve implemented that, tried to use, but it seems that nested transcation is committed only in case when external is committed also.

Please advise.

Answer 1

I’ve decided to change my ‘ExecuteWorker’ method to create transaction conditionally. Therefore I’m able to create transaction in the ‘DoLogicX’ method itself.