BreezeJs Fails to Load Metadata for EF Code First Schema with Inherited Class

Question

Just started trying out Breeze today, long time EF user - think I found a bug in Breeze, but I may be doing something wrong - want to know which it is:

I have a simple hierarchy in EF Code First:

// For testimonials about the product line in general
public class Testimonial
{
    public int Id { get; set; }

    public string Text { get; set; }
}

// For testimonials specific to a single product
[Table("ProductTestimonial")]
public class ProductTestimonial : Testimonial
{
    public Product Product { get; set; }
}

So just to be clear there's 2 tables here, Testimonial and ProductTestimonial, both have a PK of Id, and a Text field, and one of them also has an FK off to Product. This is just a simple way of implementing Table Per Type.

So I setup the BreezeController via WebApi:

[BreezeController]
public class EFController : ApiController
{
    private readonly EFContextProvider<EfDb> _db = new EFContextProvider<EfDb>();

    [HttpGet]
    public string Metadata()
    {
        return _db.Metadata();
    }

And I go to load it in breeze.js:

var manager = new breeze.EntityManager('/api/ef');
manager.executeQuery(breeze.EntityQuery.from('Product');

Kablamo. Exception. It says:

Unable to get value of the property 'propertyRef': object is null or undefined

At:

function convertFromODataEntityType(... {
    . . .
    var keyNamesOnServer = toArray(odataEntityType.key.propertyRef)...

Where odataEntityType.name == 'ProductTestimonial', and .key sure enough is undefined.

Which is true. Picking things apart, when I call executeQuery(), Breeze hits the Metadata call on the WebApi, which I verified calls and returns successfully. The massive JSON string returned from there includes:

{
    "name": "ProductTestimonial",
    "baseType": "Self.Testimonial",
    "navigationProperty": {
        "name": "Product",
        "relationship": "Self.ProductTestimonial_Product",
        "fromRole": "ProductTestimonial_Product_Source",
        "toRole": "ProductTestimonial_Product_Target"
    }
},
{
    "name": "Testimonial",
    "key": {
        "propertyRef": {
            "name": "Id"
        }
    },

So it would appear the basic issue is that the Metadata is accurately portraying ProductTestimonial as an inherited class, whose key is defined elsewhere, but Breeze.js - if I'm understanding it correctly - is naively just checking the .key property without considering superclasses. But, I could be wrong since I'm so new to Breeze.

Addendum:

I don't think it's relevant here but in case it comes up, yes I do have an IQueryable as well on the WebApi Controller:

[HttpGet]
public IQueryable<Product> Products()
{
    return _db.Context.Products;
}

Also, I recognize a potential workaround here is probably to discard TPT and make full classes for every Entity with no inheritance, but I'm really slimming my example down here - there's a lot of inheritance throughout the EF model that has to stay. If it's inheritance or Breeze, Breeze is getting the axe.

Answer 1

Edit: As of v 1.3.1 Breeze now DOES support inheritance.

Inheritance is coming but we don't have a fixed date just yet. Please vote for the feature on the Breeze User Voice. We take these suggestions very seriously.

Answer 2

I don't think manager.fetchEntityByKey works with inheritance - can any of the Breeze guys confirm whether this is correct? It seems to be picking up the inherited fields from my base class, but not the fields from my derived class. I can get the full object by using entityQuery but then I have to name every field. When I do that I'm still getting parse errors on ko bindings.