Overriding FluentNHibernate DefaultCascade for many types at once

Question

I have an abstract entity base class defined like this:

public abstract class SessionItem : Entity
{
    public virtual Session Session { get; set; }
}

In addition, I'm using auto mapping:

private AutoPersistenceModel CreateAutomappings()
{
    return AutoMap
        // configuration
        .Conventions.Add(DefaultCascade.All())
        // more configuration
}

SessionItem has several derived classes/tables, and I'd like to override the cascading policy for all of them. I tried the following:

public class SessionItemAutommapingOverride : IAutoMappingOverride<SessionItem>
{
    public void Override(AutoMapping<SessionItem> mapping)
    {
        mapping.References(x => x.Session).Cascade.None();
    }
}

But unfortunately the override is not called since SessionItem is abstract (and is not mapped). I prefer to avoid overriding it for each subclass (using IAutoMappingOverride).

Is there any way to override cascading for multiple types, without using IAutoMappingOverride<> for each one?

Answer 1

public class SessionReferenceCascadeNone : IReferenceConvention, IReferenceConventionAcceptance
{
    public void Accept(IAcceptanceCriteria<IManyToOneInspector> criteria)
    {
        criteria.Expect(x =>
            typeof(SessionItem).IsAssignableFrom(x.EntityType) &&
            x.Property.PropertyType == typeof(Session));
    }

    public void Apply(IManyToOneInstance instance)
    {
        instance.Cascade.None();
    }
}

Answer 2

Apparently this is possible by using IReferenceConvention:

public class CascadeNoneOverrideConvention : IReferenceConvention
{
    public void Apply(IManyToOneInstance instance)
    {
        // override
    }
}