New Post: Handling inheritance

Hi!

I started with ServiceStack the last days and reached the validation part today.
FluentValidation is a really nice validation lib.

I had to test this kind of polymorphism too, but i decided to do it with just one entity instead of a collection. I started using your sample code.
So you can create the exact same validators (base and inherited validators) and use them.
In my version, u just need to register them once with the PolymorphicAutoValidator:

PolymorphicAutoValidator.RegisterDerivedValidator(new HR.RoBP.Contracts.Validators.Model.EmployeeValidator());   

` So you end up with:

            RuleFor(r => r.PropertyWithABaseTypeOfPerson).SetValidator(new PolymorphicAutoValidator());

If the Property PropertyWithABaseTypeOfPerson is an Employee class, its validated with the registered EmployeeValidator.

Its up to you to implement the default Validator if the type is not defined.
I also could think of a mechanism scanning an assembly and registering all types of IValidator once. This would remove the requirement of registering each derived validator.

public class PolymorphicAutoValidator: NoopPropertyValidator
{
    private static readonly Dictionary<Type, IValidator> DerivedValidators = new Dictionary<Type, IValidator>();

    public static void RegisterDerivedValidator<TDerived>(IValidator<TDerived> derivedValidator)
    {
        DerivedValidators.Add(typeof(TDerived),derivedValidator);   
    }

    public override IEnumerable<ValidationFailure> Validate(PropertyValidatorContext context)
    {
        var type = context.PropertyValue.GetType();
        if (DerivedValidators.ContainsKey(type))
        {
            var validator = new ChildValidatorAdaptor(DerivedValidators[type]);
            return validator.Validate(context);
        }
        return null;
    }

}

```