Create a Kubernetes Deployment and Service

1. Create a namespace for the example application and add labels identifying the namespace as managed by Verrazzano and enabled for Istio.

   $ kubectl create namespace hello-helidon
   $ kubectl label namespace hello-helidon verrazzano-managed=true istio-injection=enabled
   

2. Deploy the Hello Helidon Greet application.

   apiVersion: apps/v1
   kind: Deployment
   metadata:
     annotations:
       description: Hello Helidon application
       version: v1.0.0
     labels:
       app: hello-helidon
     name: hello-helidon-deployment
     namespace: hello-helidon
   spec:
     progressDeadlineSeconds: 600
     replicas: 1
     revisionHistoryLimit: 10
     selector:
       matchLabels:
         app: hello-helidon
     strategy:
       rollingUpdate:
         maxSurge: 25%
         maxUnavailable: 25%
       type: RollingUpdate
     template:
       metadata:
         annotations:
           verrazzano.io/metricsEnabled: "true" # This annotation is used in the ServiceMonitor YAML to specify whether metrics are enabled.
           verrazzano.io/metricsPath: /metrics  # This annotation is used in the ServiceMonitor YAML to replace the metrics path.
           verrazzano.io/metricsPort: "8080"    # This annotation is used in the ServiceMonitor YAML to replace the metrics port.
         labels:
           app: hello-helidon # This label is used in the Service YAML in the selector.
       spec:
         containers:
         - image: ghcr.io/verrazzano/example-helidon-greet-app-v1:1.0.0-1-20230126194830-31cd41f
           imagePullPolicy: IfNotPresent
           name: hello-helidon-container
           ports:
           - containerPort: 8080
             name: http
             protocol: TCP
           terminationMessagePath: /dev/termination-log
           terminationMessagePolicy: File
         dnsPolicy: ClusterFirst
         restartPolicy: Always
         terminationGracePeriodSeconds: 30
   

3. Access the Hello Helidon Greet application inside the Kubernetes cluster.

   apiVersion: v1
   kind: Service
   metadata:
     labels:
       app: hello-helidon
     name: hello-helidon-deployment
     namespace: hello-helidon
   spec:
     ports:
     - name: hello-helidon-container-8080
       port: 8080
       protocol: TCP
       targetPort: 8080
     selector:
       app: hello-helidon