AutoMapper, moving away from the Obsolete Static API

Question

I am working in an existing solution. The solution uses the Windsor IoC. I have an AutomapperMappings.cs class that looks like this:

public class AutoMapperMappings
{
    public static void Configure()
    {
        AutoMapper.Mapper.Configuration
        .CreateMap<LatestUpdateModel, LatestUpdate>();

        AutoMapper.Mapper.Configuration
        .CreateMap<LatestUpdate, LatestUpdateModel>();

        AutoMapper.Mapper.Configuration
        .CreateMap<DownloadLinkModel, DownloadLink>();

        AutoMapper.Mapper.Configuration
        .CreateMap<DownloadLink, DownloadLinkModel>();

        AutoMapper.Mapper.Configuration
        .CreateMap<NavigationElementModel, NavigationElement>();

        AutoMapper.Mapper.Configuration
        .CreateMap<NavigationElement, NavigationElementModel>();

        AutoMapper.Mapper.Configuration
        .CreateMap<Promobox, PromoboxModel>();

        AutoMapper.Mapper.Configuration
        .CreateMap<PromoboxModel, Promobox>();
    }
}

In my Global.asax, I had the following:

protected void Application_Start(object sender, EventArgs e)
{
    IoCContainer();
    ConfigureAutoMapperMappings();
}

protected virtual void ConfigureAutoMapperMappings()
{
    AutoMapperMappings.Configure();
}

The above is giving me a warning saying that I should move away from the static API. So I Googled around and did some reading that suggested I change my AutomapperMappings.cs to this:

public class AutoMapperMappings
{
    public static void Configure()
    {
        var config = new MapperConfiguration(cfg =>
        {
            cfg.CreateMap<LatestUpdateModel, LatestUpdate>();
            cfg.CreateMap<LatestUpdate, LatestUpdateModel>();
            cfg.CreateMap<DownloadLinkModel, DownloadLink>();
            cfg.CreateMap<DownloadLink, DownloadLinkModel>();
            cfg.CreateMap<NavigationElementModel, NavigationElement>();
            cfg.CreateMap<NavigationElement, NavigationElementModel>();
            cfg.CreateMap<Promobox, PromoboxModel>();
            cfg.CreateMap<PromoboxModel, Promobox>();
        });
    }
}

That is all fine, but the variable var config isn't actually used anywhere, so I'm sure I need to do some more stuff, but I don't know what I need to change and where.

Answer 1

There is the tutorial "Migrating from static API".

You need to create mapper object and register it to IoC container:

public class AutoMapperMappings
{
    public static void Configure(IWindsorContainer container)
    {
        var config = new MapperConfiguration(cfg =>
        {
            cfg.CreateMap<LatestUpdateModel, LatestUpdate>();
            ...
        });

        var mapper = config.CreateMapper();

        // register your mapper here.
        container.Register(Component.For<IMapper>().Instance(mapper));
    }
}

Now you can inject your mapper to the classes that need map entities:

public class ExampleClass 
{
    private readonly IMapper _mapper;
    public ExampleClass(IMapper mapper)
    {
        _mapper = mapper;
    }

    public void DoWork()
    {
        var model = new LatestUpdateModel();
        ...
        var update = mapper.Map<LatestUpdateModel, LatestUpdate>(model);
    }
}

This migration will helps you to make your code more testable by creating mock object to IMapper interface.