helloworld-operator

Helloworld operator

This is just a simple operator to get started with Operator SDK based on the tutorial, but I wanted to change the naming so I can't just copy-paste.

Bootstrap

Used these values to setup this with operator-sdk cli:

#PWD = this folder!
operator-sdk init --domain maik.fi --repo github.com/maikdotfi/k8s-operator/helloworld-operator
# API group will be maik?
operator-sdk create api --group maik --version v1alpha1 --kind Helloworld --resource --controller

Note this means the resource apiVersion will be maik.maik.fi/v1alpha1 and kind Helloworld, which is a stupid apiVersion and I should have used another group name

Local development

Operators can be developed locally using kind and local registry (running in docker container):

cd kind
sh start.sh

Note: tested on kind 0.11.1

Tests and image build

When you run docker build/push some tests will also be run, make sure these run in a k3d cluster instead of local (unless you have etcd installed locally etc.):

export USE_EXISTING_CLUSTER=true
make docker-build docker-push

Deploy

Deploying to cluster is really simple:

make deploy

Deploying CRD

There's an example CRD in the kind folder:

kubectl apply -f helloworld-crd.yaml

k8s CRD confusion

The naming of this example didn't really please me, I couldn't even figure out how to launch the CRD firstly. Here's how to find out:

kubectl get crds
kubectl explain <name-of-crd>

The crd name looked funky but explain gives sane looking stuff still.