kustomize as library experiments

kustplay.go

package main

import (
  "sigs.k8s.io/kustomize/v3/pkg/transformers"
  "sigs.k8s.io/kustomize/v3/pkg/resmap"
  "sigs.k8s.io/kustomize/v3/pkg/transformers/config"
  "sigs.k8s.io/kustomize/v3/k8sdeps/kunstruct"
  "sigs.k8s.io/kustomize/v3/pkg/gvk"
  "sigs.k8s.io/kustomize/v3/pkg/resource"
  "fmt"
)


func main() {

  zz := `
  apiVersion: apps/v1
  kind: Deployment
  metadata:
    name: nginx
    labels:
      app: nginx
  spec:
    template:
      metadata:
        labels:
          app: nginx
      spec:
        containers:
        - name: nginx
          image: nginx
          volumeMounts:
          - name: nginx-persistent-storage
            mountPath: /tmp/ps
        volumes:
        - name: $(abc)
          emptyDir: {}
        - configMap:
            name: configmap-in-base
          name: configmap-in-base
          `

  patch := `
  apiVersion: apps/v1
  kind: Deployment
  metadata:
    name: nginx
  spec:
    template:
      spec:
        containers:
          - name: nginx
            image: "{{ .Values.image_repo }}imagename:{{ .Values.image_tag }}"
          `



  kipl := kunstruct.NewKunstructuredFactoryImpl()
  factory := resource.NewFactory(kipl)
  res, err := factory.FromBytes([]byte(zz))
  if err != nil {
    panic(err)
  }
  fmt.Println(res)

  res2, err := factory.FromBytes([]byte(patch))
  if err != nil {
    panic(err)
  }

  err = res.Patch(res2)
  if err != nil {
    panic(err)
  }
  res.SetNamespace("oo1")
  transformers.MutateField(res.Map(),
                     []string{"spec", "template", "metadata", "labels", "lelel"},
                     true,
                     //m.mutate
                     func (in interface{}) (interface{}, error) {
                       return "xxx", nil
                     })
  tr := transformers.NewRefVarTransformer(map[string]interface{}{"abc": "transformed"},
  []config.FieldSpec{{Gvk: gvk.Gvk{Version: "v1", Kind: "Deployment"}, Path: "spec/template/spec/volumes/name"},})
  rm := resmap.New()


  fmt.Printf("id: %s\n", res.CurId())

  rm.Append(res)

  tr.Transform(rm)



  //rm.AsYaml()
  yaml, _ := rm.AsYaml()
  fmt.Println(string(yaml))

}