unable to query child properties in OData with Web Api - linq

Question

I am using odata and attempting to filter queries on the properties of a child class.
I am using MongoDb to store a series of object and am wanting to query these objects using OData. The objects are auto generated from xml so there is some annoying inheritance, the basic object scenario is below.
public class Container {
public Parent Property {get; set;}
}
public class Parent {}
public class Child : Parent {
public StringWrapper Value {get; set;}
}
public class StringWrapper {
public string Value {get; set;}
}
So I have made the Container into an entity and made a controller which has the code:
public ContainerController : ODataController {
public PageResult<Container> Get(ODataQueryOptions<Container> queryOptions) {
IQueryable<Container> containers = mongoRepo.All();
var filteredContainers = queryOptions.ApplyTo(containers)
as IQueryable<Container>;
return new PageResult<Container>(filteredContainers,
Request.GetNextPageLink(),
Request.GetInlineCount());
}
}
I am then querying this with the uri:
http://...Container?$filter=Property/NS.Child/Value/Value eq 'example'
If I throw a break point after applying the queryoptions and look at the IQueryable.Expression it gives the result:
value(MongoDB.Driver.Linq.MongoQueryable`1[NS.Container])
.Where($it => (IIF((IIF((($it.Property As Child) == null), null, ($it.Property As Child).Value) == null), null, ($it.Property As Child).Value.Value) == value(System.Web.Http.OData.Query.Expressions.LinqParameterContainer+TypedLinqParameterContainer`1[System.String]).TypedProperty))
when this is then resolved I get the following error
Unable to determine the serialization information for the expression: .
Edit
I tried implementing this basic case without using the mongo db and the same query works fine. I then tried a test with the mongo C# driver for using .where with the As method this resulted in the same error.
I found the query
queryable.Where(
it => (it.Property is Child && ((Child)it.Properties).Value.Value == "example"));
works correctly and was wondering if there is a way to get the query into this form from the same uri or alternatively get the C# driver for mongodb to convert as queries into this form?

Answer 1

Can you try this instead,
var filteredContainers = queryOptions.ApplyTo(containers,
new ODataQuerySettings
{
EnableConstantParameterization = false,
HandleNullPropagation = HandleNullPropagationOption.False
});
?