Polymorphism index, exclude other documents

[Tony Aarts]

I'm trying to use polymorphism for some entities, let's say I have:

[IsRoot]
Class Animal {

   Id

   Name

}

Class Dog: Animal {

   Id

   Name

   HasTale

}

Class Cat: Animal {

   Id

   Name

   DrinksMilk

}

For conventions I use:

                Conventions = new DocumentConvention()

                {

                    FindTypeTagName = type =>

                    {

                        var parents = Types.GetInheritanceTree(type);

                        foreach (var parent in parents)

                        {

                            if (Attributes.GetAttributes<IsRootAttribute>(parent, inheritAttributes: false).HasItems())

                            {

                                return DocumentConvention.DefaultTypeTagName(parent);

                            }

                        }

                        return DocumentConvention.DefaultTypeTagName(type);

                    }

                }

A dog will be called an "animal", a cat will also be an "animal", nothing wrong with that, because there is a scenario in which I want to include both cat and dog in one index.

Now I also want to create a specific index with only "cats" to get cats which are drinking milk. What would be the easiest way to accomplish this?

In my real scenario, I got a "Planning" object, which can be eigther "AbscencePlanning", "ProjectPlanning" etc. etc. The above solution will make it possible to just get all planned items (Planning has a DateFrom, DateTo etc). So I can check everywhere if there is a duplicate planning, because of the polymorphism and the ability to query on a generic type "Project" which is available in every single assembly.

A multimap won't solve this issue, because AbsencePlanning is located in another dll (assembly) which can't access ProjectPlanning (but can access Planning) and also cannot reach the ProjectPlanning index (except when I resolve it using string, not by type). So this Polymorphism looked like a serious solution to my problem. The only thing is, I want to create a specific index for only the ProjectPlanning, but I can't find a way to only load "ProjectPlanning" objects inside my index.

Example:

Map = planning =>

                from person in planning.OfType<ProjectPlanning>()

is not working. How to get the subset of Planning??

[Oren Eini (Ayende Rahien)]

You are probably better off doing the reverse, having a multi map index for all the common stuff.

But at any rate, you can add another attribute for filtering, or just use the Raven-Clr-Type.

Oren Eini

CEO

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