NHibernate Session per Call in WCF - How to Rollback
- by Corey Coogan
I've implemented some components to use WCF with both an IoC Container (StructureMap) and the Session per Call pattern. The NHibernate stuff is most taken from here: http://realfiction.net/Content/Entry/133.
It seems to be OK, but I want to open a transaction with each call and commit at the end, rather than just Flush() which how its being done in the article.
Here's where I am running into some problems and could use some advice. I haven't figured out a good way to rollback. I realize I can check the CommunicationState and if there's an exception, rollback, like so:
public void Detach(InstanceContext owner)
{
if (Session != null)
{
try
{
if(owner.State == CommunicationState.Faulted)
RollbackTransaction();
else
CommitTransaction();
}
finally
{
Session.Dispose();
}
}
}
void CommitTransaction()
{
if(Session.Transaction != null && Session.Transaction.IsActive)
Session.Transaction.Commit();
}
void RollbackTransaction()
{
if (Session.Transaction != null && Session.Transaction.IsActive)
Session.Transaction.Rollback();
}
However, I almost never return a faulted state from a service call. I would typically handle the exception and return an appropriate indicator on my response object and rollback the transaction myself.
The only way I can think of handling this would be to inject not only repositories into my WCF services, but also an ISession so I can rollback and handle the way I want. That doesn't sit well with me and seems kind of leaky.
Anyone else handling the same problem?
