OrderPlaced.cs

namespace Sales.Contracts
{
    public class OrderPlaced
    {
        public Guid OrderId { get; set; }
        public Address ShippingAddress { get; set; }
    }

    public class Address
    {
        public string AddressLine1 { get; set; }
        public string City { get; set; }
        public string State { get; set; }
        public string Postal { get; set; }
    }
}