I am trying to setup a map to utilize open generics, but it never works at runtime. I'm using AutoMapper 5.2 in .NET Core.
I have these models:
public interface IRestData<T>
{
T Data { get; }
IPaging Paging { get; }
void SetData(T data);
void SetPaging(IPaging paging);
}
public interface IPaging
{
int Count { get; }
void SetCount(int count);
}
public class RestData<T> : IRestData<T>
{
T _data;
IPaging _paging = new Paging(0);
public RestData() {}
public RestData(T data)
{
_data = data;
if (!typeof(IEnumerable).GetTypeInfo()
.IsAssignableFrom(typeof(T)))
_paging = new Paging(data != null
? 1
: 0);
}
public RestData(T data, IPaging paging)
{
_data = data;
_paging = paging;
}
public T Data => _data;
public IPaging Paging => _paging;
public void SetData(T data) => _data = data;
public void SetPaging(IPaging paging) => _paging = paging;
}
public class Paging : IPaging
{
int _count;
public Paging() {}
public Paging(int count)
{
_count = count;
}
public int Count => _count;
public void SetCount(int count) => _count = count;
}
I want to be able to Map from one RestData<T> to another RestData<T> where T is not necessarilly the same. I create an AutoMapper.Profile that looks like this (using interface):
public class CommonProfile : Profile
{
public CommonProfile()
{
CreateMap(typeof(IRestData<>), typeof(IRestData<>))
.ConvertUsing(typeof(RestDataConverter<,>));
}
}
I also tried it like this (using concrete type):
public class CommonProfile : Profile
{
public CommonProfile()
{
CreateMap(typeof(RestData<>), typeof(RestData<>))
.ConvertUsing(typeof(RestDataConverter<,>));
}
}
This is what my RestDataConverter looks like:
public class RestDataConverter<TSource, TDestination> : ITypeConverter<IRestData<TSource>, IRestData<TDestination>>
{
public IRestData<TDestination> Convert(IRestData<TSource> source, IRestData<TDestination> destination, ResolutionContext context)
{
destination = destination ?? new RestData<TDestination>();
destination.SetData(context.Mapper.Map<TDestination>(source.Data));
destination.SetPaging(source.Paging);
return destination;
}
}
I'm trying to map between two collections of specific object types (source: RestData<List<DocumentRecord>>, dest: RestData<List<Document>>). Here are my model types:
public class DocumentRecord
{
public DateTime CreatedTs { get; set; }
public int DocumentId { get; set; }
public long FileSize { get; set; }
public DateTime LastUpdatedTs { get; set; }
public int NumberOfPages { get; set; }
public string OriginalFileName { get; set; }
public IList<PageGroupRecord> PageGroups { get; set; } = new List<PageGroupRecord>();
public string Type { get; set; }
}
public class Document
{
public int ConfigurationId { get; set; }
public DateTime CreatedTs { get; set; }
public int DocumentId { get; set; }
public string FileLocation { get; set; }
public int FileSize { get; set; }
public DateTime LastUpdatedTs { get; set; }
public int NumberOfPages { get; set; }
public string OriginalFileName { get; set; }
public IList<PageGroup> PageGroups { get; set; } = new List<PageGroup>();
public string Type { get; set; }
}
And here is the AutoMapper.Profile for these two object types:
public class ServicesProfile : Profile
{
public ServicesProfile()
{
CreateMap<Document, DocumentRecord>()
.ForMember(_ => _.Configuration, _ => _.Ignore())
.ReverseMap();
}
}
I am loading profiles in Startup.cs:
public void ConfigureServices(IServiceCollection services)
{
var mapperConfiguration = new MapperConfiguration(_ =>
{
_.AddProfile<CommonProfile>();
_.AddProfile<ServicesProfile>();
});
services.AddSingleton(mapperConfiguration);
services.AddSingleton(mapperConfiguration.CreateMapper());
}
Whenever I do a map I get this exception:
Unable to cast object of type 'RestDataConverter`2[System.Collections.Generic.List`1[DocumentRecord],System.Collections.Generic.List`1[Document]]' to type 'AutoMapper.ITypeConverter`2[RestData`1[System.Collections.Generic.List`1[DocumentRecord]],RestData`1[System.Collections.Generic.List`1[Document]]]'.
Furthermore, when I try to do something more simple (source: RestData<int>, dest: RestData<int>) such as this unit test, I get a similar exception:
public class CommonProfileTests : BaseTests
{
static CommonProfileTests()
{
Mapper.Initialize(m => m.AddProfile<CommonProfile>());
}
// This unit test passes
[Fact]
public void Configuration_Is_Valid() => AssertConfigurationIsValid();
// This unit test fails with the error below
[Fact]
public void RestData_Maps_To_RestData_Correctly()
{
var source = new RestData<int>(1, new Paging(4));
var destination = Map<RestData<int>>(source);
Assert.Equal(source.Data, destination.Data);
}
}
Same basic exception:
Unable to cast object of type 'RestDataConverter`2[System.Int32,System.Int32]' to type 'AutoMapper.ITypeConverter`2[RestData`1[System.Int32],RestData`1[System.Int32]]'.
