Docker Registry packaged to run in a Windows container.
The Dockerfile in Chapter 4 of the book packages version 2.6.1 of the registry server but there is an important security fix in version 2.6.2.
Dockerfile is an updated version of the image which packages 2.6.2 with Go 1.10.
Dockerfile.old is the original version which matches the code in the book. Don't use this unless you want to recreate the exact samples in the book. The new version fixes the security issue, and you use it in the same way.
The image on Docker Hub
dockeronwindows/ch04-registryhas been updated to the v2.6.2 release.