# Production-Ready Deployment Template
# Customize values marked with <REPLACE>

apiVersion: apps/v1
kind: Deployment
metadata:
  name: <APP_NAME>
  labels:
    app: <APP_NAME>
    version: v1
spec:
  replicas: 3
  strategy:
    type: RollingUpdate
    rollingUpdate:
      maxSurge: 1
      maxUnavailable: 0
  selector:
    matchLabels:
      app: <APP_NAME>
  template:
    metadata:
      labels:
        app: <APP_NAME>
        version: v1
      annotations:
        prometheus.io/scrape: "true"
        prometheus.io/port: "8080"
        prometheus.io/path: "/metrics"
    spec:
      serviceAccountName: <APP_NAME>
      
      securityContext:
        runAsNonRoot: true
        runAsUser: 1000
        fsGroup: 1000
      
      affinity:
        podAntiAffinity:
          preferredDuringSchedulingIgnoredDuringExecution:
          - weight: 100
            podAffinityTerm:
              labelSelector:
                matchLabels:
                  app: <APP_NAME>
              topologyKey: kubernetes.io/hostname
      
      containers:
      - name: <APP_NAME>
        image: <IMAGE>:<TAG>
        imagePullPolicy: Always
        
        ports:
        - name: http
          containerPort: 8080
          protocol: TCP
        
        env:
        - name: POD_NAME
          valueFrom:
            fieldRef:
              fieldPath: metadata.name
        - name: POD_NAMESPACE
          valueFrom:
            fieldRef:
              fieldPath: metadata.namespace
        
        envFrom:
        - configMapRef:
            name: <APP_NAME>-config
        - secretRef:
            name: <APP_NAME>-secrets
        
        resources:
          requests:
            memory: "256Mi"
            cpu: "250m"
          limits:
            memory: "512Mi"
        
        securityContext:
          readOnlyRootFilesystem: true
          allowPrivilegeEscalation: false
          capabilities:
            drop:
            - ALL
        
        livenessProbe:
          httpGet:
            path: /healthz
            port: http
          initialDelaySeconds: 30
          periodSeconds: 10
          timeoutSeconds: 5
          failureThreshold: 3
        
        readinessProbe:
          httpGet:
            path: /ready
            port: http
          initialDelaySeconds: 5
          periodSeconds: 5
          timeoutSeconds: 3
          failureThreshold: 3
        
        volumeMounts:
        - name: tmp
          mountPath: /tmp
        - name: cache
          mountPath: /var/cache
      
      volumes:
      - name: tmp
        emptyDir: {}
      - name: cache
        emptyDir: {}
      
      terminationGracePeriodSeconds: 30

---
apiVersion: v1
kind: Service
metadata:
  name: <APP_NAME>
  labels:
    app: <APP_NAME>
spec:
  type: ClusterIP
  ports:
  - port: 80
    targetPort: http
    protocol: TCP
    name: http
  selector:
    app: <APP_NAME>

---
apiVersion: autoscaling/v2
kind: HorizontalPodAutoscaler
metadata:
  name: <APP_NAME>
spec:
  scaleTargetRef:
    apiVersion: apps/v1
    kind: Deployment
    name: <APP_NAME>
  minReplicas: 3
  maxReplicas: 10
  metrics:
  - type: Resource
    resource:
      name: cpu
      target:
        type: Utilization
        averageUtilization: 70

---
apiVersion: policy/v1
kind: PodDisruptionBudget
metadata:
  name: <APP_NAME>
spec:
  minAvailable: 2
  selector:
    matchLabels:
      app: <APP_NAME>