cattle-operator

Cattle-operator is an example operator generated by operator-sdk.

---

Install operator-sdk Cli

https://github.com/operator-framework/operator-sdk/blob/master/doc/user/install-operator-sdk.md

$ go version
go version go1.12.4 linux/amd64

$ operator-sdk version
operator-sdk version: v0.8.0, commit: 78c472461e75e6c64589cfadf577a2004b8a26b3

---

Get Started

https://github.com/operator-framework/getting-started

New operator

cd ${GOPATH}/src/github.com/chechiachang

export GO111MODULE=on
OPERATOR=cattle-operator
operator-sdk new ${OPERATOR}

$ tree -L 2
.
├── cattle-operator
│   ├── build
│   ├── cmd
│   ├── deploy
│   ├── go.mod
│   ├── go.sum
│   ├── pkg
│   ├── tools.go
│   ├── vendor
│   └── version
└── README.md

Add api and controller

API_VERSION=cattle.chechiachang.com/v1alpha1
CRD=Cattle
operator-sdk add api --api-version=${API_VERSION} --kind=${CRD}
operator-sdk add controller --api-version=${API_VERSION} --kind=${CRD}

Update CRD definition

Add Spec to Cattle

vim pkg/apis/cattle/v1alpha1/cattle_types.go

type CattleSpec struct {
	Name      string   `json:"name"`
	Size      int32    `json:"size"`
	BeefParts []string `json:"beefParts"`
}

make generate

Add angus-cattle resource

cp deploy/crds/cattle_v1apha1_cattle_cr.yaml deploy/crds/angus_cattle_cr.yaml
vim deploy/crds/angus_cattle_cr.yaml

apiVersion: cattle.chechiachang.com/v1alpha1
kind: Cattle
metadata:
  name: angus-cattle
spec:
  # Add fields here
  name: angus
  beatParts:
  - chuck
  - rib
  - plate
  size: 3

Update controller reconcile logic

vim pkg/controller/cattle/cattle_controller.go

make generate

---

Test

Test on a local cluster

make local

Build Image

make build push

Deploy to kubernetes

Update image tag

make tag

(Grant extra privilege for serviceaccount rulebinding)

kubectl apply -f deploy/crds/cattle_v1alpha1_cattle_crd.yaml
kubectl apply -f deploy

Apply angus-cattle CR

kubectl apply -f deploy/crds/angus_cattle_cr.yaml