3-backend.yaml

apiVersion: v1
kind: ConfigMap
metadata:
  name: demo-backend-cm
  namespace: kubernetes-demo
data:
  MONGODB_URI: "mongodb://mongodb-0.mongodb.kubernetes-demo.svc.cluster.local:27017/sample-app"
  JAVA_OPTS: "-Dspring.profiles.active=local-docker -Xms125m -Xmx250m"

---

apiVersion: v1
kind: Service
metadata:
  name: demo-backend-deployment-service
  namespace: kubernetes-demo
  labels:
    app: demo-backend-deployment
spec:
  type: ClusterIP
  ports:
    - port: 80
  selector:
    app: demo-backend-deployment

---

apiVersion: apps/v1
kind: Deployment
metadata: 
  name: demo-backend-deployment
  labels:        
    app: demo-backend-deployment
  namespace: kubernetes-demo
spec: 
  replicas: 3
  strategy:
    type: RollingUpdate
    rollingUpdate:
      maxSurge: 1
      maxUnavailable: 0
  selector:
    matchLabels:
      app: demo-backend-deployment
  template: 
    metadata:
      labels:        
        app: demo-backend-deployment
    spec:
      containers:
        - image: cunal/demo-backend:51e393ef4be964e1c0a11cbc869d397a82700190
          imagePullPolicy: IfNotPresent
          readinessProbe:
            httpGet:
              path: /actuator/health
              port: 80
            initialDelaySeconds: 15
            periodSeconds: 5
            timeoutSeconds: 3
          resources:
            requests:
              cpu: "800m"
            limits:
              cpu: "1000m"
          name: demo-backend-deployment
          ports: 
            - containerPort: 80
          envFrom:
          - configMapRef:
              name: demo-backend-cm

---

apiVersion: autoscaling/v2beta1
kind: HorizontalPodAutoscaler
metadata:
  name: demo-backend-hpa
  namespace: kubernetes-demo
spec:
  scaleTargetRef:
    apiVersion: extensions/v1beta1
    kind: Deployment
    name: demo-backend-deployment
  minReplicas: 3
  maxReplicas: 7
  metrics:
  - type: Resource
    resource:
      name: cpu
      targetAverageUtilization: 10