Overlay StatefulSet from Workload

01-delivery-with-inline-overlay.yml

#@ load("@ytt:data", "data")
#@ load("@ytt:yaml", "yaml")
#@ load("@ytt:overlay", "overlay")

#@ def param(key):
#@   if not key in data.values.params:
#@     return None
#@   end
#@   return data.values.params[key]
#@ end

#@ def overlayvolumes():
#@overlay/match by=overlay.subset({"kind":"StatefulSet"}), expects="0+"
---
spec:
  template:
    #@overlay/match missing_ok=True
    volumeClaimTemplates: #@ param("volumeclaimtemplate")
    spec:
      #@overlay/match missing_ok=True
      volumemounts: #@ param("volumemounts")
#@ end

#@ def delivery():
---
apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: web
spec:
  selector:
    matchLabels:
      app: nginx
  serviceName: "nginx"
  replicas: 3 
  minReadySeconds: 10
  template:
    metadata:
      labels:
        app: nginx 
    spec:
      terminationGracePeriodSeconds: 10
      containers:
      - name: nginx
        image: registry.k8s.io/nginx-slim:0.8
        ports:
        - containerPort: 80
          name: web
---
apiVersion: v1
kind: Service
metadata:
  name: jeremy
spec:
---

apiVersion: apps/v1
kind: Deployment
metadata:
  name: nginx-deployment
  labels:
    app: nginx
spec:
  replicas: 3
  selector:
    matchLabels:
      app: nginx
  template:
    metadata:
      labels:
        app: nginx
    spec:
      containers:
      - name: nginx
        image: nginx:1.14.2
        ports:
        - containerPort: 80

#@ end

---
apiVersion: v1
kind: ConfigMap
metadata:
  name: my-cm
  labels: my-label
data:
  delivery.yml: #@ yaml.encode(overlay.apply(delivery(),overlayvolumes()))

02-datavalues.yaml

#@data/values
---
params:
  volumeclaimtemplate:
    - metadata:
        name: zookeeper-vol
      spec:
        accessModes:
        - ReadWriteOnce
        resources:
          requests:
            storage: 8Gi
      storageClassName: rbd
  volumemounts:
    - name: www
      mountPath: /usr/share/nginx/html