06_operator_sdk

Operator SDK

This tutorial demonstrates simple operator-sdk workflow and examines Reconcile loop which will typical Operator developer deal with.

Official Operator SDK repository.

Operator SDK tutorial

Check operator-sdk prerequisites doc before starting this tutorial.

Create minimal Operator in GOPATH:

mkdir -p $GOPATH/src/github.com/prgcont/
cd $GOPATH/src/github.com/prgcont/
operator-sdk new workshop-operator

Add API to generated Operator(shall be executed inside workshop-operator directory):

operator-sdk add api --api-version=workshopapp.operator.prgcont.cz/v1alpha1 --kind=WorkshopApp

Check which files were added or updated.

Add Controller to generated Operator:

operator-sdk add controller --api-version=workshopapp.operator.prgcont.cz/v1alpha1 --kind=WorkshopApp

Check which files were added or updated.

Build and run operator locally:

# Create CRD
kubectl create -f ./deploy/crds/workshopapp_v1alpha1_workshopapp_crd.yaml

go build ./cmd/manager
WATCH_NAMESPACE=default ./manager

# Create instance of app
kubectl create -f ./deploy/crds/workshopapp_v1alpha1_workshopapp_cr.yaml

Tasks:

• delete the pod, observe what happened and explain it
  • hint: check Reconcile method in pkg/controller/workshopapp/workshopapp_controller.go file.
• Stop Operator and delete CR, observe if Pod was deleted and explain why.