Sample Azure Vote application using topology spread to place pods in both spot and on-demand node pools

azure-vote.yaml

apiVersion: apps/v1
kind: Deployment
metadata:
  name: azure-vote-back
spec:
  replicas: 1
  selector:
    matchLabels:
      app: azure-vote-back
  template:
    metadata:
      labels:
        app: azure-vote-back
    spec:
      nodeSelector:
        "kubernetes.io/os": linux
      containers:
      - name: azure-vote-back
        image: mcr.microsoft.com/oss/bitnami/redis:6.0.8
        env:
        - name: ALLOW_EMPTY_PASSWORD
          value: "yes"
        resources:
          requests:
            cpu: 100m
            memory: 128Mi
          limits:
            cpu: 250m
            memory: 256Mi
        ports:
        - containerPort: 6379
          name: redis
---
apiVersion: v1
kind: Service
metadata:
  name: azure-vote-back
spec:
  ports:
  - port: 6379
  selector:
    app: azure-vote-back
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: azure-vote-front
spec:
  replicas: 9
  selector:
    matchLabels:
      app: azure-vote-front
  template:
    metadata:
      labels:
        app: azure-vote-front
    spec:
      affinity:
        nodeAffinity:
          requiredDuringSchedulingIgnoredDuringExecution:
            nodeSelectorTerms:
            - matchExpressions:
              - key: deploy
                operator: In
                values:
                - spot
                - ondemand
          preferredDuringSchedulingIgnoredDuringExecution:
          - weight: 99
            preference:
              matchExpressions:
              - key: deploy
                operator: In
                values:
                - spot
          - weight: 1
            preference:
              matchExpressions:
              - key: deploy
                operator: In
                values:
                - ondemand
      tolerations:
      - key: kubernetes.azure.com/scalesetpriority
        operator: Equal
        value: spot
        effect: NoSchedule
      topologySpreadConstraints:
      - labelSelector:
          matchLabels:
            app: azure-vote-front
        maxSkew: 3
        topologyKey: deploy
        whenUnsatisfiable: DoNotSchedule
      - labelSelector:
          matchLabels:
            app: azure-vote-front
        maxSkew: 1
        topologyKey: topology.kubernetes.io/zone
        whenUnsatisfiable: ScheduleAnyway
      containers:
      - name: azure-vote-front
        image: mcr.microsoft.com/azuredocs/azure-vote-front:v1
        resources:
          requests:
            cpu: 100m
            memory: 128Mi
          limits:
            cpu: 250m
            memory: 256Mi
        ports:
        - containerPort: 80
        env:
        - name: REDIS
          value: "azure-vote-back"
---
apiVersion: v1
kind: Service
metadata:
  name: azure-vote-front
spec:
  type: LoadBalancer
  ports:
  - port: 80
  selector:
    app: azure-vote-front