Resolve dependencies only from specified namespace

Question

I can automatically register all types that implement interfaces with this statement

IUnityContainer container = new UnityContainer();

container.RegisterTypes(
    AllClasses.FromAssembliesInBasePath(),
    WithMappings.FromMatchingInterface,
    WithName.Default,
    WithLifetime.Transient);
ICustomer result = container.Resolve<ICustomer>();

How can I specify a namespace for interfaces and implementations?

i.e: only interfaces in Framework.RepositoryInterfaces should get resolved by types in Framework.RepositoryImplementations.

Answer 1

You can use the RegistrationConvention :

public class NamespaceRegistrationConvention : RegistrationConvention
{
    private readonly IEnumerable<Type> _typesToResolve;
    private readonly string _namespacePrefixForInterfaces;
    private readonly string _namespacePrefixForImplementations;

    public NamespaceRegistrationConvention(IEnumerable<Type> typesToResolve, string namespacePrefixForInterfaces, string namespacePrefixForImplementations)
    {
        _typesToResolve = typesToResolve;
        _namespacePrefixForInterfaces = namespacePrefixForInterfaces;
        _namespacePrefixForImplementations = namespacePrefixForImplementations;
    }

    public override IEnumerable<Type> GetTypes()
    {
        // Added the abstract as well. You can filter only interfaces if you wish.
        return _typesToResolve.Where(t =>
            ((t.IsInterface || t.IsAbstract) && t.Namespace.StartsWith(_namespacePrefixForInterfaces)) ||
            (!t.IsInterface && !t.IsAbstract && t.Namespace.StartsWith(_namespacePrefixForImplementations)));
    }

    public override Func<Type, IEnumerable<Type>> GetFromTypes()
    {
        return WithMappings.FromMatchingInterface;
    }

    public override Func<Type, string> GetName()
    {
        return WithName.Default;
    }

    public override Func<Type, LifetimeManager> GetLifetimeManager()
    {
        return WithLifetime.Transient;
    }

    public override Func<Type, IEnumerable<InjectionMember>> GetInjectionMembers()
    {
        return null;
    }
}

And use it via:

container.RegisterTypes(new NamespaceRegistrationConvention(AllClasses.FromAssembliesInBasePath(), "Framework.RepositoryInterfaces", "Framework.RepositoryImplementations");
ICustomer result = container.Resolve<ICustomer>();