NHibernate ManyToMany relationship - using AuditInterceptor - object references an unsaved transient instance - save the transient instance before flushing

Question

The domain model the DomainObject's audit fields are populated using an AuditInterceptor.

DomainObject
   Id
   EstablishDate
   EstablishId
   UpdateDate
   UpdateId

Message : DomainObject
   Description
   MessageDistributions

Distribution : DomainObject
   BeginEffective
   EndEffective
   MessageDistributions

MessageDistribution : DomainObject
   Distribution
   Message

In this ManyToMany relationship the MessageDistribution also implements the DomainObject in order to use the AuditInterceptor. This keeps me from using the HasManyToMany clause in the FluentNHibernate Mapping.

Here is the mapping code.

public class MessageMap : ClassMap<Message>
{
  public MessageMap()
    {
        WithTable("Message");

        Id(x => x.Id).GeneratedBy.Identity().ColumnName("MessageSeq").WithUnsavedValue(0);
        Map( x => x.Description ).ColumnName( "SummaryName" );
        Map(x => x.EstablishDate);
        Map(x => x.EstablishId);
        Map(x => x.UpdateDate);
        Map(x => x.UpdateId);


        HasMany( x => x.MessageDistributions )
            .KeyColumnNames.Add( "MessageSeq" )
            .Access.AsCamelCaseField( Prefix.Underscore )
            .Cascade.All().Inverse();

    }
}

public class MessageDistributionMap : ClassMap<MessageDistribution>
{
    public MessageDistributionMap()
    {
        WithTable("MessageDistribution");

        Id(x => x.Id).GeneratedBy.Identity().ColumnName("MessageDistributionSeq").WithUnsavedValue(0);

        Map(x => x.EstablishDate);
        Map(x => x.EstablishId);
        Map(x => x.UpdateDate);
        Map(x => x.UpdateId);

        References(x => x.Message).ColumnName("MessageSeq");
        References(x => x.Distribution).ColumnName("DistributionSeq");
    }
}

public class DistributionMap : ClassMap<Distribution>
{
    public DistributionMap()
    {
        WithTable("Distribution");

        Id(x => x.Id).GeneratedBy.Identity().ColumnName("DistributionSeq").WithUnsavedValue(0);

        Map(x => x.BeginEffectiveDate);
        Map(x => x.EndEffectiveDate);
        Map(x => x.EstablishDate);
        Map(x => x.EstablishId);
        Map(x => x.UpdateDate);
        Map(x => x.UpdateId);

        HasMany( x => x.MessageDistributions )
            .KeyColumnNames.Add( "DistributionSeq" )
            .Access
            .AsCamelCaseField( Prefix.Underscore )
            .Cascade.All().Inverse();
    }
}

Below is a test to implement the above relationship.

[Test]
public void Should_Add_A_Message_To_Existing_Distribution()
{
    var desc = "Test message " + DateTime.Now;
    var message = new Message { Description = desc, PumpType = 1 };

    var distribution = new Distribution
                           {
                               BeginEffectiveDate = new DateTime( 2009, 9, 2 ),
                               EndEffectiveDate = new DateTime( 2009, 9, 10 ),
                               Priority = 1
                           };
    var messageDistribution = new MessageDistribution { Distribution = distribution };

    message.AddMessageDistribution(messageDistribution);

    _repository.Save( message );
    _repository.Clear();

    var retrievedMessage = _repository.GetById(message.Id);

    Assert.AreEqual(message, retrievedMessage);

    Assert.AreEqual(distribution, retrievedMessage.MessageDistributions[0].Distribution);
}

I execute the test using a test runner and it results in the following error on the line _repository.Save( message );

    NHibernate.TransientObjectException: 
    object references an unsaved transient instance - 
save the transient instance before flushing: 
    Speedway.StoreOperations.CrindMessaging.Core.Domain.Distribution

In my AuditInterceptor I have a

Debug.WriteLine(string.Format("{0} : {1}", propertyNames[i], state[i]));

in the "OnSave and OnFlushDirty" events.

I can see the Message and MessageDistribution are coming through but the Distribution entity never gets touched.

So my question is, is there something wrong with my FluentMapping? Do I have the "Inverse" in the wrong place? Has anyone run across this situation?

Answer 1

Your FluentMapping looks OK. Try to change the following line in your test:

var messageDistribution = new MessageDistribution { Distribution = distribution };

with this:

var messageDistribution = new MessageDistribution { Distribution = distribution, Message = message };

and try again.