apiVersion: v1
kind: Service
metadata:
  name: datastore
spec:
  clusterIP: None
  selector:
    app: datastore
  ports:
  - name: http
    port: 80
---
apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: datastore
  annotations:
    statefulsets.kubernetes.io/scaledown-pod-template: |
      {
        "metadata": {
          "labels": {
            "app": "datastore-cleanup"
          }
        },
        "spec": {
          "terminationGracePeriodSeconds": 5,
          "containers": [
            {
              "name": "main",
              "image": "busybox",
              "command": ["/bin/sh", "-c", "echo \"Cleaning up data... this takes 10 seconds!\" ; sleep 10 ; rm /var/data/test.txt; echo \"Data deleted!\""],
              "volumeMounts": [
                {
                  "name": "data",
                  "mountPath": "/var/data"
                }
              ]
            }
          ]
        }
      }
spec:
  updateStrategy:
    type: RollingUpdate
  serviceName: datastore
  replicas: 3
  selector:
    matchLabels:
      app: datastore
  template:
    metadata:
      labels:
        app: datastore
    spec:
      terminationGracePeriodSeconds: 5
      containers:
      - name: main
        image: busybox
        command:
        - /bin/sh
        - -c
        - 'echo "data" > /var/data/test.txt ; echo "Data written! Sleeping for a very long time..." ; sleep 99999999'
        ports:
        - name: http
          containerPort: 8080
        volumeMounts:
        - name: data
          mountPath: /var/data
  volumeClaimTemplates:
  - metadata:
      name: data
    spec:
      resources:
        requests:
          storage: 1Mi
      accessModes:
      - ReadWriteOnce