Docker container Jekyll Ruby

Musings around a Dockerfile for Jekyll

If you like cool stories about how an engineer, faced with an impossible problem, overcame all odds and solved it, this post is not for you. This is a story of how I spent a non-trivial amount of time, how I hit a couple of walls, and how I nearly came back to square one. Why do I write it? The first reason is for me: I want to document my journey so if I ever think about trying again in the future, I’ll have some arguments against it. Second, in opposition to the actual zeitgeist, you le

Kubernetes container initialization configuration

The versatility of Kubernetes' initContainer

There are a lot of different ways to configure containers running on Kubernetes: Environment variablesConfig mapsVolumes shared across multiple podsArguments passed to scheduled podsetc. Those alternatives fit a specific context, with specific requirements. For example, none of them allow you to clone a Git repository before the container starts. It would be possible to design that feature into the image itself. Yet, that would introduce coupling, and defeat the Single Responsibility principl

container build optimization

Strategies for optimizing Maven Docker images

Last week, I wrote on how to design a generic Docker image for Maven-based auto-executable webapps. The designed build file has 3 different stages: checkout from Github, build with Maven and execute with Java. The Maven build stage takes quite a long time, mostly due to: Executing testsDownloading dependencies Tests can be executed earlier in the build chain - then skipped for Docker, this post will focus on speeding up the download of the dependencies. Let’s check each option in turn.