Helm

Demo - Kubernetes Helm

Install Helm

curl -fsSL -o get_helm.sh https://raw.githubusercontent.com/helm/helm/main/scripts/get-helm-3
chmod 700 get_helm.sh
./get_helm.sh

With Chocolatey (package manager for Windows)

Run the following in PowerShell as Administrator

Set-ExecutionPolicy AllSigned

Set-ExecutionPolicy Bypass -Scope Process -Force; [System.Net.ServicePointManager]::SecurityProtocol = [System.Net.ServicePointManager]::SecurityProtocol -bor 3072; iex ((New-Object System.Net.WebClient).DownloadString('https://community.chocolatey.org/install.ps1'))

choco install kubernetes-helm

Verify

helm ls

Deploy the app with Helm

  1. Create a Helm Chart

    helm create todo-app
    • Delete all files in the /templates directory and copy all Kubernetes manifests to it
    mongo-express-deployment.yaml
mongo-express-service.yaml
mongo-init-job.yaml
mongodb-service.yaml
mongodb-statefulset.yaml
todo-configmap.yaml
todo-deployment.yaml
todo-service.yaml

  2. Install the chart as a release

    helm install todo-app-release ./todo-app
helm ls
kubectl get all
    • Verify by opening a browser and go to the todo app

  3. Uninstall the release

    helm uninstall todo-app-release
helm ls
kubectl get all

Deploy on GKE

  1. Edit the Helm file values.yaml

    values.yaml

    serviceType: NodePort

  2. Create another Helm file values-gke.yaml

    values-gke.yaml

    serviceType: LoadBalancer

  3. Update the type in the template yaml-files to {{ .Values.serviceType }}

    mongo-express-service.yaml

    apiVersion: v1
kind: Service
metadata:
  name: mongo-express-service
spec:
  selector:
    app: mongo-express
  ports:
    - protocol: TCP
      port: 8081
      targetPort: 8081
  type: {{ .Values.serviceType }}

    todo-service.yaml

    apiVersion: v1
kind: Service
metadata:
 name: todo-service
spec:
 selector:
   app: todo-webapp
 ports:
 - protocol: TCP
   port: 80
   targetPort: 80
 type: {{ .Values.serviceType }}

  4. Switch kubectl

    kubectl config get-contexts
kubectl config use-context <GKE>
kubectl config current-context

  5. Install the Helm chart

    helm install todo-app-release ./todo-app --values ./todo-app/values-gke.yaml
helm ls
kubectl get all

  6. Uninstall the release

    helm uninstall todo-app-release
helm ls
kubectl get all