IMapper<TFrom, TTo>

Mapper.cs

namespace Payment.System.Provider.Core.Interfaces
{
    public interface IMapper<in TFrom, out TTo>
    {
        TTo Map(TFrom from);
    }
}

namespace Payment.System.Provider.Ping.Mappers
{
    public class OrderMapper : IMapper<Ping.Models.Order, Payment.System.Models.Order>
    {
        public Payment.System.Models.Order Map(Ping.Models.Order from) => new Payment.System.Models.Order
        {
            Id = from.Id,
            ...
        };
    }
}

namespace Payment.System.Provider.Ping.Clients
{
    public class OrderClient : BaseClient, IOrderClient
    {
        private static readonly IMapper<Ping.Models.Order, Payment.System.Models.Order> OrderMapper = new OrderMapper();

        public OrderClient(IOptions options)
            : base(options)
        {
        }

        public async Task<Payment.System.Models.Order> GetAsync(Ping.Requests.Order.Get request)
        {
            var result = await base.GetAsync<Ping.Responses.Order>($"order/{request.Id}");

            return OrderMapper.Map(result);
        }

        public async Task<IEnumerable<Payment.System.Models.Order>> FindAsync(Ping.Requests.Order.Find request)
        {
            var result = await base.GetAsync<IEnumerable<Payment.System.Models.Order>, Ping.Requests.Order.Find>($"orders");

            return OrderMapper.Map(result);
        }
    }
}