dev.yaml

---

apiVersion: v1
kind: Namespace
metadata:
  name: test
  labels:
    name: test

---

apiVersion: v1
kind: ConfigMap
metadata:
  name: test-config
  namespace: test
data:
  postgres_name: "dvdrental"
  postgres_host: "postgres"
  postgres_port: "5432"

---

apiVersion: v1
kind: Secret
metadata:
  name: postgres-secret
  namespace: test
data:
  username: "cG9zdGdyZXM="
  password: "cCQxa0IjeU1RWEdu"
---
apiVersion: v1
kind: PersistentVolume
metadata:
  name: pv0001
  namespace: test
spec:
  accessModes:
    - ReadWriteOnce
  capacity:
    storage: 5Gi
  hostPath:
    path: /data_ext/k8s_pv/pv1  
---

kind: PersistentVolumeClaim
apiVersion: v1
metadata:
  name: postgres-pvc
  namespace: test
  labels:
    app: postgres
spec:
#  storageClassName: aws-gp2
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 2Gi

---
apiVersion: v1
kind: ConfigMap
metadata:
  name: upgrade-script
  namespace: test
data:
  pre.sh: |
    #!/bin/bash
    if [ ! -f /var/lib/postgresql/data/pgdata/PG_VERSION ]; then
    echo "No data in the volume"
    exit 0
    fi
    if [ `cat /var/lib/postgresql/data/pgdata/PG_VERSION` -eq "$NEW_VER" ]; then
    echo "Same ver, no need to upgrade"
    exit 0
    fi
    apt-get update && apt-get install -y postgresql-"$OLD_VER"
    ls /tmp/scripts
    su - postgres -c "POSTGRES_USER=$POSTGRES_USER OLD_VER=$OLD_VER NEW_VER=$NEW_VER bash /tmp/scripts/upgrade.sh"
  upgrade.sh: |
    #!/bin/bash
    echo "$OLD_VER - $NEW_VER"
    mkdir /tmp/pgdata-"$OLD_VER"
    mv /var/lib/postgresql/data/pgdata/* /tmp/pgdata-"$OLD_VER"/
    chmod -R 750 /tmp/pgdata-"$OLD_VER"
    ls -al /tmp/pgdata-"$OLD_VER"
    /usr/lib/postgresql/$NEW_VER/bin/initdb -E UTF8 --lc-collate en_US.UTF-8 --lc-ctype en_US.utf8 --username="$POSTGRES_USER" -D /var/lib/postgresql/data/pgdata
    cd /var/lib/postgresql/; /usr/lib/postgresql/"$NEW_VER"/bin/pg_upgrade -U "$POSTGRES_USER" -b /usr/lib/postgresql/"$OLD_VER"/bin/ -B /usr/lib/postgresql/"$NEW_VER"/bin/ -d /tmp/pgdata-"$OLD_VER" -D /var/lib/postgresql/data/pgdata
    ./delete_old_cluster.sh
---
kind: Deployment
apiVersion: apps/v1
metadata:
  name: postgres
  namespace: test
  labels:
    app: postgres
spec:
  replicas: 1
  selector:
    matchLabels:
      app: postgres
  template:
    metadata:
      labels:
        app: postgres
    spec:
      initContainers:
      - name: upgrade
        image: postgres:12
        command: ['sh', '-c', 'bash /tmp/scripts/pre.sh']
        env:
        - name: OLD_VER
          value: "11"
        - name: NEW_VER
          value: "12"          
        - name: POSTGRES_DB
          valueFrom:
            configMapKeyRef:
              name: test-config
              key: postgres_name
        - name: POSTGRES_USER
          valueFrom:
            secretKeyRef:
              name: postgres-secret
              key: username
        - name: POSTGRES_PASSWORD
          valueFrom:
            secretKeyRef:
              name: postgres-secret
              key: password
        volumeMounts:
        - mountPath: /var/lib/postgresql/data
          name: postgre-storage
        - name: script
          mountPath: /tmp/scripts          
          
      containers:
      - name: postgres
        image: postgres:11
        ports:
        - name: postgres
          containerPort: 5432
        env:
        - name: POSTGRES_DB
          valueFrom:
            configMapKeyRef:
              name: test-config
              key: postgres_name
        - name: POSTGRES_USER
          valueFrom:
            secretKeyRef:
              name: postgres-secret
              key: username
        - name: POSTGRES_PASSWORD
          valueFrom:
            secretKeyRef:
              name: postgres-secret
              key: password
        - name: PGDATA
          value: /var/lib/postgresql/data/pgdata
        volumeMounts:
        - mountPath: /var/lib/postgresql/data
          name: postgre-storage
      volumes:
      - name: postgre-storage
        persistentVolumeClaim:
          claimName: postgres-pvc
      - name: script
        configMap:
          name: upgrade-script
          items:
            - key: pre.sh
              path: pre.sh
            - key: upgrade.sh
              path: upgrade.sh