Random “Missing type map configuration or unsupported mapping.” Error in Automapper

Question

Please see this post for the solution.

Ok, I finally figured it out. The: AppDomain.CurrentDomain.GetAssemblies() piece of my code sometimes does not

Answer 1

For me this error had to do with where I put my CreateMap<>() call. I had put it in the static initializer for my DTO. When I moved the CreateMap<>() call to somewhere less cute, everything worked fine.

Answer 2

If you use Mapper.AssertConfigurationIsValid(); you would get bit more detailed info:

Unmapped members were found. Review the types and members below. Add a custom mapping expression, ignore, add a custom resolver, or modify the source/destination type

In any case, you have to have mapped all properties of destination model. You were missing CityDTO and Id. Here:

Mapper.CreateMap<City, CityDTO>();

Mapper.CreateMap<Country, CountryDTO>()
    .ForMember(dto => dto.Id, options => options.Ignore())
    .ForMember(dto => dto.Longtitude, mc => mc.MapFrom(e => e.CountryCoordinate.Longtitude))
    .ForMember(dto => dto.Lattitude, mc => mc.MapFrom(e => e.CountryCoordinate.Lattitude));

Maybe you would need some additional mapping on City-CityDTO, as you did not specify them.