Helm

Complete Helm Chart Tutorial: From Beginner to Expert Guide

Introduction

Helm is the best way to find, share, and use software built for Kubernetes.

How to install helm ?

  • for MasOS: brew install helm

How Helm Chart help us to manage k8s?

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    kubectl apply -f deployment.yaml
    kubectl apply -f service.yaml
    kubectl apply -f ingress.yaml

    kubectl delete -f deployment.yaml
    kubectl delete -f service.yaml
    kubectl delete -f ingress.yaml
  • to 
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    helm install my-app ./my-chart

    helm uninstall my-app

Architecture

high-level architecture


Helm Demo

demo code link: https://github.com/mjd507/helm-demo

  1. Create a helm chart.

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    helm create helm-demo

  2. check the directorys

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    ➜  cd helm-demo
    ➜  tree
    .
    ├── Chart.yaml
    ├── charts
    ├── templates
    │   ├── NOTES.txt
    │   ├── _helpers.tpl
    │   ├── deployment.yaml
    │   ├── hpa.yaml
    │   ├── ingress.yaml
    │   ├── service.yaml
    │   ├── serviceaccount.yaml
    │   └── tests
    │       └── test-connection.yaml
    └── values.yaml

    change the service type to NodePort in value.yaml

  3. install chart to k8s

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    cd ..
    helm install my-helm-demo helm-demo

  4. verify helm install command

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    helm list -a

    output:
    NAME            NAMESPACE       REVISION        UPDATED                                 STATUS   CHART            APP VERSION
    my-helm-demo    default         1               2024-02-16 14:46:06.11394 +0800 CST     deployed helm-demo-0.1.0  1.16.0

  5. check the service/pod in k8s

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    kubectl get service
    output:
    NAME             TYPE        CLUSTER-IP       EXTERNAL-IP   PORT(S)          AGE
    ...
    my-helm-demo     NodePort    10.101.215.130   <none>        80:31348/TCP     2m28s

    kubectl get pods
    output:
    NAME                                 READY   STATUS    RESTARTS        AGE
    ...
    my-helm-demo-5b77995cb9-q4cz9        1/1     Running   0               2m39s

  6. check within the broswer
    since I use minikube to build a local k8s cluster, I can use minikube commands to verify the pod/service. it will open the page with my default broswer.

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    minikube service my-helm-demo

  7. remove from k8s

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    helm uninstall my-helm-demo