The Custom Controller (crd-controller) is created to manage a Custom Resource (Kluster)

Learning Custom Resource Definition and Sample Controller

Goals:

• Understand CRs
• Define a CR using CRD
• Understand Custom Controller
• Write a Custom Controller (crd-controller) to manage a Custom Resource (Kluster)

Info:

• Group Name: neajmorshad.dev
• Version Name: v1beta1
• Resource Name: Kluster

Procedure to run this project:

• go to the project path. Example: $HOME/go/src/github.com/Neaj-Morshad-101/crd-controller/
• import "k8s.io/code-generator" into main.go
• run go install sigs.k8s.io/controller-tools/cmd/controller-gen@latest
• run go mod tidy;go mod vendor
• run chmod +x ./hack/update-codegen.sh
• run chmod +x vendor/k8s.io/code-generator/generate-groups.sh
• run hack/update-codegen.sh
• again run go mod tidy;go mod vendor

To generate controller-gen:

• Run depelopmentDir=$(pwd)
• Then run: controller-gen rbac:roleName=controller-perms crd paths=github.com/Neaj-Morshad-101/crd-controller/pkg/apis/neajmorshad.dev/v1beta1 crd:crdVersions=v1 output:crd:dir=$depelopmentDir/manifests output:stdout

Deploy Custom resources

• kubectl apply -f neajmorshad.dev_klusters.yaml
• Create an example yaml file like manifests/kluster.yaml.
• Run kubectl apply -f manifests/kluster.yaml.
• Run kubectl get kluster.

Resource

https://www.linkedin.com/pulse/kubernetes-custom-controllers-part-1-kritik-sachdeva/ https://www.linkedin.com/pulse/kubernetes-custom-controller-part-2-kritik-sachdeva/ Workqueue example: https://github.com/kubernetes/client-go/tree/master/examples/workqueue Sample-controller https://github.com/kubernetes/sample-controller Code-Generator https://github.com/kubernetes/code-generator

This YouTube video will help to understand the basic structure of a Custom Controller

https://www.youtube.com/watch?v=89PdRvRUcPU&list=PLh4KH3LtJvRTtFWz1WGlyDa7cKjj2Sns0&index=4&ab_channel=VivekSingh