Support C# interface to edm model builder

[xuzhg]

C# interface can't work now in the latest product codes.

Here's a proposal how to implement the interface in Web API OData:

For example:

public interface IA
{
    int AProp {get;set;}
}

public interface IB
{
   string BProp {get;set;}
}

public abstract class C
{
    public string CProp {get;set;}
}

public class class D : C, IA, IB
{
   public string DProp {get;set;}
}

So, type D should have a based type of C, and two implementions for the interface IA and IB.

In OData, the implementor for IA and IB should be used as annotation for the type of D.

for example (prototype):

<EntityType Name="C" Abstract="True">
  ...
</EntityType>
<EntityType Name="D" BasedType="C" >
   ....
   <Annotation Name="Core.Implementation" Value="NS.IA, NS.IB" />
</EntityType>

<ComplexType Name="IA" >
   ...
</ComplexType>
<ComplexType Name="IB">
  ...
</ComplexType>

Where, the IA and IBare reserved as Complex type.

Then, we can do:

Get ~/odata/Ds(key)/DProp
Get ~/odata/Ds(key)/CProp       //success. because D has the whole properties from base type
Get ~/odata/Ds(key)/Ns.C/CProp  // Success.
Get ~/odata/Ds(key)/AProp      // failed. because D doesn't have the property from interface.
Get ~/odata/Ds(key)/NS.IA/AProp  // success.
Get ~/odata/Ds(key)/NS.IB/BProp  // success.

A lot of customers are asking for the support for the interface. So . please do some investigation.

[xuzhg]

@mikepizzo

Hi, Mikep, do we have the similar annotation defined in the Core annotation?

[Jamaxack]

Any updates?

[weitzhandler]

Related: https://github.com/OData/odata.net/issues/1746

[weitzhandler]

@xuzhg

Where, the IA and IBare reserved as Complex type.

How will clients (such as ODataConnectedService) identify IA and IB as interfaces?

[komdil]

any progress?