# HorizontalPodAutoscaler — CPU/memory + custom metric
apiVersion: autoscaling/v2
kind: HorizontalPodAutoscaler
metadata:
  name: <APP_NAME>
  namespace: <NAMESPACE>
spec:
  scaleTargetRef:
    apiVersion: apps/v1
    kind: Deployment
    name: <APP_NAME>
  minReplicas: 3                  # HA için en az 3
  maxReplicas: 30
  behavior:
    scaleUp:
      stabilizationWindowSeconds: 60
      policies:
        - type: Percent
          value: 100              # 60sn'de %100 (2x) artırabilir
          periodSeconds: 60
        - type: Pods
          value: 4                # veya 4 pod ekle
          periodSeconds: 60
      selectPolicy: Max
    scaleDown:
      stabilizationWindowSeconds: 300        # 5dk yavaş azalt (oscillation engelle)
      policies:
        - type: Percent
          value: 50
          periodSeconds: 60
  metrics:
    - type: Resource
      resource:
        name: cpu
        target:
          type: Utilization
          averageUtilization: 70
    - type: Resource
      resource:
        name: memory
        target:
          type: Utilization
          averageUtilization: 80
    # Custom metric örneği (Prometheus Adapter kurulu olmalı):
    # - type: Pods
    #   pods:
    #     metric:
    #       name: http_requests_per_second
    #     target:
    #       type: AverageValue
    #       averageValue: "100"