Question

I am developing a ASP.NET MVC web app under .NET 3.5, NHibernate and hosted on Windows Azure. When, the webapp is run from the local development fabric it works fine. Yet, when I move it to Windows Azure, every insert performed from the MVC web role ends up with the exception listed below.

Any idea what’s wrong with my NHibernate logic? (might be the session management, not sure)

[AssertionFailure: null id in Lokad.Translate.Entities.User entry (don’t flush the Session after an exception occurs)]
NHibernate.Event.Default.DefaultFlushEntityEventListener.CheckId(Object obj, IEntityPersister persister, Object id, EntityMode entityMode) +292
NHibernate.Event.Default.DefaultFlushEntityEventListener.GetValues(Object entity, EntityEntry entry, EntityMode entityMode, Boolean mightBeDirty, ISessionImplementor session) +93
NHibernate.Event.Default.DefaultFlushEntityEventListener.OnFlushEntity(FlushEntityEvent event) +158
NHibernate.Event.Default.AbstractFlushingEventListener.FlushEntities(FlushEvent event) +469
NHibernate.Event.Default.AbstractFlushingEventListener.FlushEverythingToExecutions(FlushEvent event) +339
NHibernate.Event.Default.DefaultFlushEventListener.OnFlush(FlushEvent event) +85
NHibernate.Impl.SessionImpl.Flush() +275
NHibernate.Transaction.AdoTransaction.Commit() +236
Lokad.Translate.Repositories.PageRepository.Create(Page page)
Lokad.Translate.Controllers.PagesController.Create(Page page)
lambda_method(ExecutionScope , ControllerBase , Object[] ) +69
System.Web.Mvc.ReflectedActionDescriptor.Execute(ControllerContext controllerContext, IDictionary2 parameters) +251
System.Web.Mvc.ControllerActionInvoker.InvokeActionMethod(ControllerContext controllerContext, ActionDescriptor actionDescriptor, IDictionary2 parameters) +31
System.Web.Mvc.<>c__DisplayClassa.b__7() +88
System.Web.Mvc.ControllerActionInvoker.InvokeActionMethodFilter(IActionFilter filter, ActionExecutingContext preContext, Func1 continuation) +534
System.Web.Mvc.ControllerActionInvoker.InvokeActionMethodWithFilters(ControllerContext controllerContext, IList1 filters, ActionDescriptor actionDescriptor, IDictionary`2 parameters) +312
System.Web.Mvc.ControllerActionInvoker.InvokeAction(ControllerContext controllerContext, String actionName) +856
System.Web.Mvc.Controller.ExecuteCore() +185
System.Web.Mvc.MvcHandler.ProcessRequest(HttpContextBase httpContext) +221
System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +586
System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +177

Note that I am using _session.FlushMode = FlushMode.Commit; and that the User is used in a custom RoleProvider

public class SimpleRoleProvider : RoleProvider 
{
    readonly UserRepository Users = new UserRepository();

    public override string[] GetRolesForUser(string username)
    {
        try
        {
            var user = Users.Get(username);

            // no role if user is not registered
            if (null == user) return new string[0];

            // default role for registered user
            return user.IsManager ? new[] { "Manager", "User" } : new[] { "User" };
        }
        catch (Exception)
        {
            // role should not fail in case of DB issue.
            return new string[0];
        }
    }
}

Answer 1

I have finally found a solution to my own problem. In case people would be interested, I am posting the solution here.

public class SimpleRoleProvider : RoleProvider 
{
    // isolated session management for the RoleProvider to avoid
    // issues with automated management of session lifecycle.

    public override string[] GetRolesForUser(string username)
    {
        using (var session = GlobalSetup.SessionFactory.OpenSession())
        {
            var users = new UserRepository(session);
            var user = users.Get(username);

            // no role if user is not registered
            if (null == user) return new string[0];

            // default role for registered user
            return user.IsManager ? new[] {"Manager", "User"} : new[] {"User"};
        }
    }
}

Basically what was happening is that the RoleProvider repository does not seem to have the same lifecycle than regular in-view / in-controller repositories. As a result, at the time the RoleProvider is called, the NHibernate session has already been disposed causing the exception observed here above.

I have replaced the code by the following one here above. This one has its own NHibernate session management, and ends up working fine.