advancedextension

README

Advanced Extension Example

This directory contains an example of extending the kubebuilder config-gen by creating a second kustomize transformer plugin which is composed with config-gen.

Prerequisites

• kustomize example
• KubebuilderConfigGen schema types.go

Install the extension as a plugin

The extension is a separate plugin composed with the config-gen plugin.

# build the extension
go build -o ~/go/bin/advancedextension .

# setup the extension plugin
export XDG_CONFIG_HOME=$HOME/.config
export KUBEBUILDER_PLUGIN=$XDG_CONFIG_HOME/kustomize/plugin/kubebuilder.sigs.k8s.io/kubebuilderconfiggenadvancedextension
mkdir -p $KUBEBUILDER_PLUGIN
cat > $KUBEBUILDER_PLUGIN/KubebuilderConfigGenAdvancedExtension <<EOF
#!/bin/bash 
KUSTOMIZE_FUNCTION=true advancedextension
EOF
chmod +x $KUBEBUILDER_PLUGIN/KubebuilderConfigGenAdvancedExtension

Modify the kustomization.yaml

Add the extensinon as a transformer to the kustomization.yaml

apiVersion: kustomize.config.k8s.io/v1beta1
kind: Kustomization

transformers:
# this is the original kubebuilder configuration generator
- |-
  apiVersion: kubebuilder.sigs.k8s.io/v1alpha1
  kind: KubebuilderConfigGen
  metadata:
    name: example
  spec:
    crds:
      # contains kubebuilder project go code for generating crds
      projectDirectory: ../../testdata/project/...

    controllerManager:
      # image containing controller-manager
      image: example/simple:latest
# this is the extension which modifies the output from the KubebuilderConfigGen
- |-
  apiVersion: kubebuilder.sigs.k8s.io
  kind: KubebuilderConfigGenAdvancedExtension
  metadata:
    name: example
  replicas: 5

Run kustomize

kustomize build --enable-alpha-plugins .

See types.go for the KubebuilderConfigGen schema.