Add a WebAPI OData $orderby option in an ODataController

Question

I've written a OData WebAPI controller inherting from ODataController.

public class ManyColumnsController : ODataController
{
    [Queryable(
        AllowedOrderByProperties = "Aa,Bb,Cc,Dd",
        EnsureStableOrdering = false,
        MaxOrderByNodeCount = 2)]
    public IQueryable<ManyColumn> GetManyColumns(
            ODataQueryOptions<ManyColumn> options)
    {
        // Because I've disabled EnsureStableOrdering,
        // I need to check column "Dd" is always included
        // in the OrderBy option.
        if (!options.OrderBy.RawValue.Contains("Dd")
        {
            // I need to add an OrderByPropertyNode to
            // options.OrderBy.OrderByNodes. 
        }

        return this.context.ManyColumns;
    }
}

How can I instantiate an OrderByNode to add to the generic collection exposed by OrderByQueryOption?

---

You'll note that one constructor of OrderByNode takes an IEdmProperty. I feel there should me some trivial way to find an instance of IEdmProperty from the IEdmModel exposed at options.Context.Model. and the IEdmType at options.Context.ElementType.

If this is achievable, I could use the instance in place of the string search in the if statement. In addition to adding it to the whole OrderByClause.

Answer 1

IEdmEntityType entityType=options.Context.ElementType as Microsoft.OData.Edm.IEdmEntityType;
IEdmStructuralProperty property = entityType.DeclaredStructuralProperties().Single(p => p.Name == "Dd");
IEdmType edmType=property.Type.Definition;

Answer 2

You can get the property just as Jinfu said,

but I think you can new an OrderByQueryOption and call ApplyTo to meet your requirement.

var result = this.context.ManyColumns;
if (!options.OrderBy.RawValue.Contains("Dd")
{
    var orderBy = new OrderByQueryOption("Dd", new ODataQueryContext(Request.GetEdmModel(), typeof(ManyColumn)));
    result = orderBy.ApplyTo(result );
}