Why does Nhibernate share the session across multiple requests in my MVC application?

Question

We have an MVC project that constructs the NHibernate dependecies via StructureMap like this

var sessionFactory = ConnectionRegistry.CreateSessionFactory<         


        

Answer 1

The problem is combination of a singleton:

For<INHibernateSessionManager>().Singleton().Use<NHibernateWebSessionManager>();

Having reference to an object from a different scope (webrequest context)

_currentSession = SessionFactory.GetCurrentSession();

This canot work properly in multithread environment (as mentioned in cases of two concurrent browsers accessing it). First request could already force to set the field _currentSession, which is then (for a while) used even for the second one. The first Application_EndRequest will close it ... and lasting one will recreate it...

When relying on NHibernate scopes, follow it fully:

return SessionFactory.GetCurrentSession(); // inside is the scope handled

SessionManager.Open()

public ISession OpenSession()
{
  if(CurrentSessionContext.HasBind(SessionFactory))
  {
     return SessionFactory.GetCurrentSession();
  }
  // else  
  var session = SessionFactory.OpenSession();
  NHibernate.Context.CurrentSessionContext.Bind(session);
  return session;
}

Then even singleton returning correct instances should work. But for a SessionManager I would use HybridHttpOrThreadLocalScoped anyway.

For<INHibernateSessionManager>()
  .HybridHttpOrThreadLocalScoped()
  .Use<NHibernateWebSessionManager>();