2. Deploy BoxOffice

apiVersion: kustomize.config.k8s.io/v1beta1
kind: Kustomization
namespace: boxoffice
labels:
  - pairs:
      app.kubernetes.io/part-of: boxoffice
resources:
  - namespace.yaml
  - config.yaml
  - db.yaml
  - redis.yaml
  - catalog.yaml
  - catalog-hpa.yaml
  - ingress.yaml

apiVersion: kustomize.config.k8s.io/v1beta1
kind: Kustomization
resources:
  - ../../base
images:
  - name: boxoffice/catalog          # the name used in base/catalog.yaml...
    newTag: dev                      # ...and the tag loaded into the local cluster
secretGenerator:
  - name: db-credentials             # lab only: real secrets never live in Git in plain text
    namespace: boxoffice
    literals:
      - DB_USER=boxoffice
      - DB_PASSWORD=boxoffice

apiVersion: v1
kind: Namespace
metadata:
  name: boxoffice

# Non-secret settings shared by the services (the same variables as in docker-compose.yaml)
apiVersion: v1
kind: ConfigMap
metadata:
  name: boxoffice-config
data:
  DB_HOST: db
  DB_PORT: "5432"
  DB_NAME: boxoffice
  REDIS_HOST: redis
  REDIS_PORT: "6379"

# PostgreSQL as a StatefulSet: a stable name (db-0) and its own persistent volume.
# Fine for a lab; in production use a managed database or an operator (e.g. CloudNativePG).
apiVersion: v1
kind: Service
metadata:
  name: db
spec:
  clusterIP: None            # headless: DNS "db" resolves to the pod itself
  selector:
    app: db
  ports:
    - name: postgres
      port: 5432
---
apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: db
spec:
  serviceName: db
  replicas: 1
  selector:
    matchLabels:
      app: db
  template:
    metadata:
      labels:
        app: db
    spec:
      containers:
        - name: postgres
          image: postgres:17
          ports:
            - name: postgres
              containerPort: 5432
          env:
            - name: POSTGRES_DB
              valueFrom:
                configMapKeyRef: { name: boxoffice-config, key: DB_NAME }
            - name: POSTGRES_USER
              valueFrom:
                secretKeyRef: { name: db-credentials, key: DB_USER }
            - name: POSTGRES_PASSWORD
              valueFrom:
                secretKeyRef: { name: db-credentials, key: DB_PASSWORD }
            - name: PGDATA
              value: /var/lib/postgresql/data/pgdata
          readinessProbe:
            exec:
              command: ["sh", "-c", "pg_isready -U \"$POSTGRES_USER\" -d \"$POSTGRES_DB\""]
            periodSeconds: 5
          resources:
            requests: { cpu: 250m, memory: 256Mi }
            limits: { cpu: "1", memory: 1Gi }
          volumeMounts:
            - name: data
              mountPath: /var/lib/postgresql/data
  volumeClaimTemplates:
    - metadata:
        name: data
      spec:
        accessModes: ["ReadWriteOnce"]
        resources:
          requests:
            storage: 2Gi

apiVersion: v1
kind: Service
metadata:
  name: redis
spec:
  selector:
    app: redis
  ports:
    - name: redis
      port: 6379
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: redis
spec:
  replicas: 1
  selector:
    matchLabels:
      app: redis
  template:
    metadata:
      labels:
        app: redis
    spec:
      containers:
        - name: redis
          image: redis:8-alpine
          args: ["--maxmemory", "256mb", "--maxmemory-policy", "allkeys-lru"]
          ports:
            - name: redis
              containerPort: 6379
          readinessProbe:
            exec:
              command: ["redis-cli", "ping"]
            periodSeconds: 5
          resources:
            requests: { cpu: 100m, memory: 128Mi }
            limits: { cpu: 500m, memory: 320Mi }