One chart to rule them all

This repo is part of my blogpost with the same title: https://sanderverbruggen.com/one-chart-to-rule-them-all/

After reading it, come back to play with this setup and try the different approaches from the post by yourself.

Building and running the Spring Boot application

./gradlew bootRun

will result in an error because of missing property as mentioned in the blogpost. You'll need to provide a Spring profile to run it locally. The pro file local has been provided. To run the app with this, do:

./gradlew bootRun --args='--spring.profiles.active=local'

This will give you two endpoints to curl or open in your browser:

• http://localhost:8080/messages/motd
• http://localhost:8080/messages/quote

If you play around with the application-local.yaml you can enable either/both of these endpoints:

• http://localhost:8080/alpha/awesomeResult
• http://localhost:8080/beta/quiteStable

Setting up a local Kubernetes cluster

You'll need docker, but I presume you have that running or know how to install it.

k3d is a simple, lightweight Kubernetes cluster manager for local clusters. The simplest way to install it is through Homebrew. After installing Homebrew, run this from the project folder:

brew install k3d helm kubectl
k3d cluster create one-chart -p "8090:30080@agent:0" --agents 2

After a few seconds, you will have your cluster up and running.

Installing the app using the helm chart

The go to the helm/one-chart folder and run

helm install one-chart . -f values.yaml

This will pull the docker image of the Spring Boot app and run it using the values.yaml in this folder. You now have access to the same 4 endpoints as listed above, only now they're running on port 8090 (e.g. http://localhost:8090/messages/motd)

Now you can play with the contents of values.yaml. After saving it, use helm to upgrade (install is only for the first time) your deployed app:

helm upgrade one-chart . -f values.yaml

After a few seconds the app should be working with your changed settings!

Done with all of this?

Time to clean up:

k3d cluster delete one-chart