22-web-deployment-v2.yaml

apiVersion: apps/v1
kind: Deployment
metadata:
  name: web
  namespace: reliability-lab
  labels:
    lesson: reliability
    app: web
spec:
  replicas: 3
  minReadySeconds: 5
  revisionHistoryLimit: 10
  strategy:
    type: RollingUpdate
    rollingUpdate:
      maxSurge: 1
      maxUnavailable: 1
  selector:
    matchLabels:
      lesson: reliability
      app: web
  template:
    metadata:
      labels:
        lesson: reliability
        app: web
    spec:
      terminationGracePeriodSeconds: 30
      containers:
      - name: web
        image: busybox:1.36
        imagePullPolicy: IfNotPresent
        command:
        - sh
        - -c
        - |
          mkdir -p /www
          httpd -f -p 8080 -h /www &
          while true; do
            printf 'version=%s\npod=%s\nnode=%s\ntime=%s\n' \
              "${APP_VERSION}" \
              "$(hostname)" \
              "${NODE_NAME}" \
              "$(date '+%Y-%m-%dT%H:%M:%S%z')" > /www/index.html
            if [ -f /tmp/fail-readiness ]; then
              rm -f /www/ready
            else
              printf 'ok\n' > /www/ready
            fi
            if [ -f /tmp/fail-liveness ]; then
              rm -f /www/live
            else
              printf 'ok\n' > /www/live
            fi
            sleep 2
          done
        env:
        - name: APP_VERSION
          value: v2
        - name: NODE_NAME
          valueFrom:
            fieldRef:
              fieldPath: spec.nodeName
        lifecycle:
          preStop:
            exec:
              command:
              - sh
              - -c
              - |
                rm -f /www/ready
                sleep 20
        ports:
        - name: http
          containerPort: 8080
        readinessProbe:
          httpGet:
            path: /ready
            port: http
          periodSeconds: 3
          failureThreshold: 1
        livenessProbe:
          httpGet:
            path: /live
            port: http
          initialDelaySeconds: 5
          periodSeconds: 5
          failureThreshold: 2
        resources:
          requests:
            cpu: 10m
            memory: 32Mi