pg-slave-statefulset.yaml.back2

# pg-slave-statefulset.yaml
apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: pg-slave
spec:
  serviceName: pg-slave
  replicas: 1  # For simplicity, one slave; increase replicas if needed
  selector:
    matchLabels:
      app: postgres
      role: slave
  template:
    metadata:
      labels:
        app: postgres
        role: slave
    spec:
      containers:
      - name: postgres
        image: postgres:15
        env:
        - name: POSTGRES_USER
          value: "postgres"
        - name: POSTGRES_PASSWORD
          value: "password"
        - name: PGDATA
          value: "/var/lib/postgresql/data"
        volumeMounts:
        - name: pg-data
          mountPath: /var/lib/postgresql/data
        securityContext:
            runAsUser: 999  # PostgreSQL user UID
            runAsGroup: 999  # PostgreSQL group GID
        command:
        - "bash"
        - "-c"
        - |
          # Extract replica name from the pod's hostname (e.g., pg-slave-0)
          REPLICA_NAME=$(hostname | sed 's/-/_/g')

          rm -rf /var/lib/postgresql/data/*  # Ensure the directory is empty
          until pg_isready --host=pg-master --port=5432; do
            echo "Waiting for master to be ready..."
            sleep 2
          done
          pg_basebackup -h pg-master -D /tmp/pgdata -U postgres -v -P --wal-method=stream
          mv /tmp/pgdata/* /var/lib/postgresql/data/
          chown -R postgres:postgres /var/lib/postgresql/data
          psql -h pg-master  -U postgres -c "SELECT pg_create_physical_replication_slot('${REPLICA_NAME}');"
          echo "primary_slot_name = '${REPLICA_NAME}'" |  tee -a /var/lib/postgresql/data/postgresql.conf
          echo "primary_conninfo = 'host=pg-master port=5432 user=postgres password=password application_name=${REPLICA_NAME}'" |  tee -a  /var/lib/postgresql/data//postgresql.conf
          touch /var/lib/postgresql/data/standby.signal
          chmod 700 /var/lib/postgresql/data/
          rm -rf /tmp/pgdata
          echo "Starting PostgreSQL..."
          postgres

      volumes:
      - name: pg-data
        persistentVolumeClaim:
          claimName: pg-slave-pvc  # Reference pre-created PVC