Automapper in WebAPI Controller

Question

I have a Car WebAPI controller method as below - note _carService.GetCarData returns a collection of CarDataDTO objects

[HttpGet]
[Route("api/Car/Retrieve/{carManufacturerID}/{year}")]
public IEnumerable<CarData> RetrieveTest(int carManufacturerID, int year)
{
    //Mapper.Map<>
    var cars = _carService.GetCarData(carManufacturerID, year);
    //var returnData = Mapper.Map<CarData, CarDataDTO>();
    return cars;
}

CarData is a WebAPI model I have created.

public class CarData
{
    public string Model { get; set; }
    public string Colour { get; set; }
    //other properties removed from brevity
}

CarDataDTO is a class I have created that models the DB Table - I retrieve the Data via a stored proc called with dapper.

public class CarDataDTO
{
    public int CarID { get; set; }
    public int CarManufacturerID { get; set; }
    public int Year { get; set; }
    public string Model { get; set; }
    public string Colour { get; set; }
    //other properties removed from brevity
}

If I have a breakpoint on the var cars line in my API controller I can see everything returned as expected and I have a collection of CarDTO objects. However, I don't require the WebAPI to return the CarDataID, CarID or Year which is why I created the CarData API model.

How can I easily use Automapper to only map the properties I am concerned with?

Do I need something set up in my WebApiConfig class?

Solution

You could install the AutoMapper nuget package from: AutoMapper And then declare a class like:

public class AutoMapperConfig
{
    public static void Initialize()
    {
        Mapper.Initialize((config) =>
        {
            config.CreateMap<Source, Destination>().ReverseMap();
        });
    }
}

And then call this in your Global.asax like this:

public class WebApiApplication : System.Web.HttpApplication
{
    protected void Application_Start()
    {
        AutoMapperConfig.Initialize();
        GlobalConfiguration.Configure(WebApiConfig.Register);
    }
}

And if you would like to ignore certain properties then you could do something like this:

Mapper.CreateMap<Source, Destination>()
  .ForMember(dest => dest.SomePropToIgnore, opt => opt.Ignore())

And the way you use this for mapping is:

DestinationType obj = Mapper.Map<SourceType, DestinationType>(sourceValueObject);
List<DestinationType> listObj = Mapper.Map<List<SourceType>, List<DestinationType>>(enumarableSourceValueObject);