[JustWatch] Artificer (Docker container builder)

The source code for this project can be found at
https://github.com/justwatchcom/artificer

Motivation

At JustWatch we had a Kubernetes system and we used it to build and deploy our programs as containers to stage or production. The problem was that we couldn't really use Docker from inside the containers to build the container images.

Implementation

I started the project by looking at the Docker container files and reverse engineering them. They are fairly complex, but not that complex, and human readable. And they were fairly well documented. I considered writing a complete custom program but it turned out that once you knew how to build such an image, you could just use a go library from Google called google/go-containerregistry which would do most of the job.

The utility allows you to specify a baseimage, a number of files to include as well as optionally additional environment variables and it allows you to override the CMD. Then it would use this to build a new container and upload it to the provided Container Registry.

Future

The project has been open sourced by my former employer JustWatch and is effectively fully working.