Quering Web API 2.2 with lowerCamelCase - odata

Question

I am using Web API 2.2 with the [EnableQuery] like this:
public class ProductsController : ApiController
{
private MyContext db = new MyContext();
[EnableQuery]
public IQueryable<Product> GetProducts()
{
return db.Products;
}
}
Once I am using CamelCasePropertyNamesContractResolver I would like to perform an OData query like this: api/products/?$expand=categories instead of api/products/?$expand=Categories.
I tested the OData v4 (which I dont want use because the DateTime properties) using ODataController and it works:
ODataConventionModelBuilder builder = new ODataConventionModelBuilder();
builder.EnableLowerCamelCase();
So, I wonder if is this possible with ApiController ?

Answer 1

You need to do the following steps:
Define a custom EnableQueryAttribute:
public class MyEnableQueryAttribute:EnableQueryAttribute
{
public override IEdmModel GetModel(Type elementClrType, HttpRequestMessage request,
HttpActionDescriptor actionDescriptor)
{
// Get model for the request
IEdmModel model = request.ODataProperties().Model;
if (model == null)
{
// user has not configured anything or has registered a model without the element type
// let's create one just for this type and cache it in the action descriptor
model = actionDescriptor.Properties.GetOrAdd("System.Web.OData.Model+" + elementClrType.FullName, _ =>
{
ODataConventionModelBuilder builder =
new ODataConventionModelBuilder(actionDescriptor.Configuration, isQueryCompositionMode: true);
builder.EnableLowerCamelCase();
EntityTypeConfiguration entityTypeConfiguration = builder.AddEntityType(elementClrType);
builder.AddEntitySet(elementClrType.Name, entityTypeConfiguration);
IEdmModel edmModel = builder.GetEdmModel();
Contract.Assert(edmModel != null);
return edmModel;
}) as IEdmModel;
}
Contract.Assert(model != null);
return model;
}
}
Add it to the actions in the controller:
public class ProductsController : ApiController
{
[MyEnableQuery]
public IHttpActionResult Get()
{
IList<Product> products=new List<Product>();
products.Add(new Product() { Id = 1, Name = "Name1",Category=new Category(){Id=1,Name="Category1" }});
products.Add(new Product() { Id = 2, Name = "Name2", Category = new Category() { Id = 2, Name = "Category2" } });
return Ok(products.AsQueryable<Product>());
}
}
then it is able to query with camel case:
GET http://localhost:12568/api/Products?$expand=category
I've put the whole solution here: https://github.com/tanjinfu/WebApiODataSamples/tree/master/EnableCamelCaseForApiController, FYI.