How to register & use WebAPI with Attribute Routes in Umbraco V8

WebApiAttributeRoutes.cs

using System.Web.Http;
using Umbraco.Core;
using Umbraco.Core.Components;

namespace My.Website
{
    [RuntimeLevel(MinLevel = RuntimeLevel.Run)]
    public class ApiComposer : IUserComposer
    {
        public void Compose(Composition composition)
        {
            composition.Components().Append<ApiComponent>();
        }
    }

    public class ApiComponent : IComponent
    {
        public void Initialize()
        {
            GlobalConfiguration.Configuration.MapHttpAttributeRoutes();
        }

        public void Terminate()
        {
        }
    }

    public class OrdersController : ApiController
    {
        [Route("customers/{customerId}/orders")]
        [HttpGet]
        public string FindOrdersByCustomer(int customerId)
        {
            return $"Fetching orders for {customerId} who has XX orders";
        }
    }
}