Sample Metadata for ASP.NET WebAPi service composition

ExternalApiMetadata.cs

[Export(typeof(IComposableApiMetadata))]
  public class ExternalApiMetadata : IComposableApiMetadata {
    public void Compose(ContainerBuilder builder) {
      builder.Register(e => new BookRepository()).As<IBookRepository>().InstancePerApiRequest();
    }
  
    public Assembly ApiAssembly() {
      return typeof(BooksController).Assembly;
    }
  }