Expanding Properties on Derived Types

[Norm-Cota]

Hello,

I am using this library via https://github.com/diegomvh/angular-odata and have run into something that isn't currently supported. (I think)

My API has some derived types that I am trying to expand. It seems that odata-query is not able to describe the cast to the derived type in object form and manually entering the cast as a string value is interpreted as a nested expand. I understand the benefit of the string valued shorthand, but it precludes the ability to cast to the derived type.

Here is a contrived scenario:
Namespace: Example
Entities:

• Shape { ID: number }
• Circle : Shape { Radius: number }
• Square : Shape { Size: number, Vertices: Vertex[] }
• Vertex

Endpoints:

• /Shapes
• /Vertices

If I want to query all of the Shapes but expand the Vertices for any Square objects, the query would be:

[root]/Shapes?$expand=Example.Square/Vertices

The object form doesn't have the ability to specify type, which isn't too big a deal since it is a more complex scenario. However, passing the string of "Example.Square/Vertices" to the expand property results in the this query:

[root]/Shapes?$expand=Example.Square($expand=Vertices)

Obviously, the above isn't correct given the model.

I realize that removing or modifying the string shorthand would be a large breaking change for many. Given that, is there a workaround for this scenario? Would it be possible to add this ability within the object form? Other ideas?

Quick Edit: OData v4

[erzet]

👍 To that, it looks like it's impossible to expand properly using namespace cause '/' is translated to property expansion. Any chance this will get some love?

[Feeedi]

I would also love this feature!