Helm chart 생성, 배포

작성일: 2021-11-03

Kubernetes 패키지 매니저 도구인 helm을 통해 chart 생성 및 Kubernetes 배포

K3S 환경에서 테스트

Helm

https://helm.sh/
Kubernetes 배포를 위한 패키지 매니저 툴 (e.g yum, choco)
chart 라는 yaml 파일 기반의 템플릿 파일을 통해 패키지화 및 Kubernetes 설치 관리
- Deployment, Service, Ingress 등 Kubernetes 서비스의 manifest 생성 및 설치
Helm Repository 를 통해 패키지 등록 및 다른 패키지 설치 가능

Helm Install

바이너리 직접 설치 및 설치 Script 활용
Homebrew, Chocolatey 등의 패키지로도 설치 가능

바이너리 다운로드

https://github.com/helm/helm/releases

$ curl -LO https://get.helm.sh/helm-v3.7.1-linux-amd64.tar.gz
$ tar -zxvf helm-v3.7.1-linux-amd64.tar.gz

$ tree linux-amd64
linux-amd64
├── LICENSE
├── README.md
└── helm

$ sudo cp linux-amd64/helm /usr/local/bin/

설치 Script 활용

$ 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

Creating Your Own Charts

kubernetes 설치를 위한 chart 생성 및 세팅
https://helm.sh/docs/helm/helm_create/

# chart 생성
$ helm create mvcapp
Creating mvcapp

Chart directory 구조

Chart.yaml : Chart 버전, 이미지버전, 설명등을 기술하는 파일
values.yaml : manifest template 파일 기반, 기준 값을 세팅하는 파일
templates/ : kubernetes manifest template 파일
charts/ : chart 의존성 파일

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

`Chart.yaml` 수정

version : Chart 버전
appVersion : Deploy 되는 image 버전

apiVersion: v2
name: mvcapp
description: .net core test mvc application
# ... 생략
type: application
# ... 생략
version: 0.1.0
# ... 생략
appVersion: "0.6"  # appVersion: "1.16.0"

`values.yaml` 수정

replicaCount : Pod 의 replica 개수, 2개로 수정
image.repository : docker image 이름, cdecl/mvcapp 로 수정
service.type : On-Premise에서 테스트 목적, NodePort로 수정
service.nodePort : nodePort를 적용하기 위해 신규 추가

# Default values for mvcapp.
# This is a YAML-formatted file.
# Declare variables to be passed into your templates.

replicaCount: 2

image:
  repository: cdecl/mvcapp
  pullPolicy: IfNotPresent
  # Overrides the image tag whose default is the chart appVersion.
  tag: ""

imagePullSecrets: []
nameOverride: ""
fullnameOverride: ""

# ... 생략

service:
  type: NodePort   # ClusterIP
  port: 80
  nodePort: 30010

ingress:

# ... 생략

resources: {}
  # We usually recommend not to specify default resources and to leave this as a conscious
  # choice for the user. This also increases chances charts run on environments with little
  # resources, such as Minikube. If you do want to specify resources, uncomment the following
  # lines, adjust them as necessary, and remove the curly braces after 'resources:'.
  # limits:
  #   cpu: 100m
  #   memory: 128Mi
  # requests:
  #   cpu: 100m
  #   memory: 128Mi

# ... 생략

`templates/service.yaml` 수정

nodePort 를 적용하기 위해 template 수정
spec.ports.nodePort: {{ .Values.service.nodePort }} 추가

apiVersion: v1
kind: Service
metadata:
  name: {{ include "mvcapp.fullname" . }}
  labels:
    {{- include "mvcapp.labels" . | nindent 4 }}
spec:
  type: {{ .Values.service.type }}
  ports:
    - port: {{ .Values.service.port }}
      targetPort: http
      protocol: TCP
      name: http
      nodePort: {{ .Values.service.nodePort }}
  selector:
    {{- include "mvcapp.selectorLabels" . | nindent 4 }}

`helm lint` : chart 파일 검사

https://helm.sh/docs/helm/helm_lint/

$ helm lint mvcapp
==> Linting mvcapp
[INFO] Chart.yaml: icon is recommended

1 chart(s) linted, 0 chart(s) failed

`helm template` : kubernetes manifest 생성

https://helm.sh/docs/helm/helm_template/
values.yaml 에 세팅한 기준으로 manifest 생성

$ helm template mvcapp
---
# Source: mvcapp/templates/serviceaccount.yaml
apiVersion: v1
kind: ServiceAccount
metadata:
  name: RELEASE-NAME-mvcapp
  labels:
    helm.sh/chart: mvcapp-0.1.0
    app.kubernetes.io/name: mvcapp
    app.kubernetes.io/instance: RELEASE-NAME
    app.kubernetes.io/version: "0.6"
    app.kubernetes.io/managed-by: Helm
---
# Source: mvcapp/templates/service.yaml
apiVersion: v1
kind: Service
metadata:
  name: RELEASE-NAME-mvcapp
  labels:
    helm.sh/chart: mvcapp-0.1.0
    app.kubernetes.io/name: mvcapp
    app.kubernetes.io/instance: RELEASE-NAME
    app.kubernetes.io/version: "0.6"
    app.kubernetes.io/managed-by: Helm
spec:
  type: NodePort
  ports:
    - port: 80
      targetPort: http
      protocol: TCP
      name: http
  selector:
    app.kubernetes.io/name: mvcapp
    app.kubernetes.io/instance: RELEASE-NAME
---
# Source: mvcapp/templates/deployment.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
  name: RELEASE-NAME-mvcapp
  labels:
    helm.sh/chart: mvcapp-0.1.0
    app.kubernetes.io/name: mvcapp
    app.kubernetes.io/instance: RELEASE-NAME
    app.kubernetes.io/version: "0.6"
    app.kubernetes.io/managed-by: Helm
spec:
  replicas: 2
  selector:
    matchLabels:
      app.kubernetes.io/name: mvcapp
      app.kubernetes.io/instance: RELEASE-NAME
  template:
    metadata:
      labels:
        app.kubernetes.io/name: mvcapp
        app.kubernetes.io/instance: RELEASE-NAME
    spec:
      serviceAccountName: RELEASE-NAME-mvcapp
      securityContext:
        {}
      containers:
        - name: mvcapp
          securityContext:
            {}
          image: "cdecl/mvcapp:0.6"
          imagePullPolicy: IfNotPresent
          ports:
            - name: http
              containerPort: 80
              protocol: TCP
          livenessProbe:
            httpGet:
              path: /
              port: http
          readinessProbe:
            httpGet:
              path: /
              port: http
          resources:
            {}
---
# Source: mvcapp/templates/tests/test-connection.yaml
apiVersion: v1
kind: Pod
metadata:
  name: "RELEASE-NAME-mvcapp-test-connection"
  labels:
    helm.sh/chart: mvcapp-0.1.0
    app.kubernetes.io/name: mvcapp
    app.kubernetes.io/instance: RELEASE-NAME
    app.kubernetes.io/version: "0.6"
    app.kubernetes.io/managed-by: Helm
  annotations:
    "helm.sh/hook": test
spec:
  containers:
    - name: wget
      image: busybox
      command: ['wget']
      args: ['RELEASE-NAME-mvcapp:80']
  restartPolicy: Never

`helm install` : chart 활용 kubernetes service install

https://helm.sh/docs/helm/helm_install/
install : helm install [NAME] [CHART] [flags]

# 설치하지는 않고 테스트 
$ helm install mvcapp-svc mvcapp --dry-run

# 로컬 Chart 를 통한 설치 
$ helm install mvcapp-svc mvcapp
NAME: mvcapp-svc
LAST DEPLOYED: Thu Nov  4 13:29:38 2021
NAMESPACE: default
STATUS: deployed
REVISION: 1
NOTES:
1. Get the application URL by running these commands:
  export NODE_PORT=$(kubectl get --namespace default -o jsonpath="{.spec.ports[0].nodePort}" services mvcapp-svc)
  export NODE_IP=$(kubectl get nodes --namespace default -o jsonpath="{.items[0].status.addresses[0].address}")
  echo http://$NODE_IP:$NODE_PORT

$ kubectl get svc
NAME         TYPE        CLUSTER-IP      EXTERNAL-IP   PORT(S)        AGE
kubernetes   ClusterIP   10.43.0.1       <none>        443/TCP        78d
mvcapp-svc   NodePort    10.43.202.254   <none>        80:31503/TCP   29s

$ kubectl get pod
NAME                          READY   STATUS    RESTARTS   AGE
mvcapp-svc-78ff4d97f9-hd9rf   1/1     Running   0          37s
mvcapp-svc-78ff4d97f9-x4984   1/1     Running   0          37s

KS3 export KUBECONFIG=/etc/rancher/k3s/k3s.yaml 세팅

`helm upgrade`, `helm uninstall`

upgrade : helm upgrade [NAME] [CHART] [flags]
uninstall : helm uninstall [NAME]

$ helm upgrade mvcapp-svc mvcapp
Release "mvcapp-svc" has been upgraded. Happy Helming!
NAME: mvcapp-svc
LAST DEPLOYED: Thu Nov  4 13:44:54 2021
NAMESPACE: default
STATUS: deployed
REVISION: 5
...

# helm list
$ helm list
NAME            NAMESPACE       REVISION        UPDATED                                 STATUS          CHART          APP VERSION
mvcapp-svc      default         5               2021-11-04 13:44:54.170028077 +0900 KST deployed        mvcapp-0.1.0   0.6

# helm history
$ helm history mvcapp-svc
REVISION        UPDATED                         STATUS          CHART           APP VERSION     DESCRIPTION
1               Thu Nov  4 13:42:12 2021        superseded      mvcapp-0.1.0    0.6             Install complete
2               Thu Nov  4 13:42:58 2021        superseded      mvcapp-0.1.0    0.5             Upgrade complete
3               Thu Nov  4 13:43:40 2021        superseded      mvcapp-0.1.0    0.6             Rollback to 1
4               Thu Nov  4 13:44:32 2021        superseded      mvcapp-0.1.0    0.5             Upgrade complete
5               Thu Nov  4 13:44:54 2021        deployed        mvcapp-0.1.0    0.6             Upgrade complete

# helm uninstall
$ helm uninstall mvcapp-svc
release "mvcapp-svc" uninstalled

Chart package, repository

`helm package`

https://helm.sh/docs/helm/helm_package/
chart 디렉토리를 압축하여 패키지화

$ helm package mvcapp
Successfully packaged chart and saved it to: /home/cdecl/temp/helm/mvcapp-0.1.0.tgz

Local repository directory

https://helm.sh/docs/helm/helm_repo_index/
helm repo index : 패키지된 차트의 Index 파일 생성

# repository local directory
$ mkdir chart-repo

# index 파일 생성 
$ helm repo index chart-repo

$ cat chart-repo/index.yaml
apiVersion: v1
entries: {}
generated: "2021-11-04T14:00:37.388050909+09:00"

# chart package 파일 넣기
$ mv mvcapp-0.1.0.tgz chart-repo

# index 파일 갱신
$ helm repo index chart-repo

$ cat chart-repo/index.yaml
apiVersion: v1
entries:
  mvcapp:
  - apiVersion: v2
    appVersion: "0.6"
    created: "2021-11-04T14:02:46.688756427+09:00"
    description: A Helm chart for Kubernetes
    digest: ff28f1c2434531c801bf68106bd5b314e4ff90adac5619e6856d9765052afb83
    name: mvcapp
    type: application
    urls:
    - mvcapp-0.1.0.tgz
    version: 0.1.0
generated: "2021-11-04T14:02:46.688277626+09:00"

Github chart repository 활용

github repository 생성 및 local repository directory push
github repository page 세팅

Repository 등록 및 설치

github page url 로 등록

# add
$ helm repo add github https://cdecl.github.io/chart-repo/
"github" has been added to your repositories

# list 
$ helm repo list
NAME    URL
stable  https://charts.helm.sh/stable
github  https://cdecl.github.io/chart-repo/

# search
$ helm search repo mvcapp
NAME            CHART VERSION   APP VERSION     DESCRIPTION
github/mvcapp   0.1.0           0.6             A Helm chart for Kubernetes

# install from repository
$ helm install mvcapp-svc github/mvcapp
NAME: mvcapp-svc
LAST DEPLOYED: Fri Nov  5 15:46:24 2021
NAMESPACE: default
STATUS: deployed
REVISION: 1
NOTES:
1. Get the application URL by running these commands:
  export NODE_PORT=$(kubectl get --namespace default -o jsonpath="{.spec.ports[0].nodePort}" services mvcapp-svc)
  export NODE_IP=$(kubectl get nodes --namespace default -o jsonpath="{.items[0].status.addresses[0].address}")
  echo http://$NODE_IP:$NODE_PORT

ConfigMap 적용

templates/ 경로에 ConfigMap yaml 파일 생성
- templates/configmap.yaml
내부에 .Files.Get "PATH" 로 정의된 PATH 파일을 패키지 디렉토리에 위치

$ cat mvcapp/templates/configmap.yaml
apiVersion: v1
kind: ConfigMap
metadata:
  name: {{ .Release.Name }}-configmap
data:
  config.json: |-
{{ .Files.Get "config.json" | indent 4}}

$ cat mvcapp/config.json
{ "url": "https://cdecl.github.io/" }

$ helm template mvcapp
---
# ... 생략 
---
# Source: mvcapp/templates/configmap.yaml
apiVersion: v1
kind: ConfigMap
metadata:
  name: RELEASE-NAME-configmap
data:
  config.json: |-
    { "url": "https://cdecl.github.io/" }
---
# ... 생략 

Byung Kyu KIM

Helm chart 생성, 배포

Helm

Helm Install

바이너리 다운로드

설치 Script 활용

Creating Your Own Charts

Chart directory 구조

`Chart.yaml` 수정

`values.yaml` 수정

`templates/service.yaml` 수정

`helm lint` : chart 파일 검사

`helm template` : kubernetes manifest 생성

`helm install` : chart 활용 kubernetes service install

`helm upgrade`, `helm uninstall`

Chart package, repository

`helm package`

Local repository directory

Github chart repository 활용

Repository 등록 및 설치

ConfigMap 적용

댓글남기기

참고

macOS Homebrew Cask, 추가 애플리케이션

모던 CMake 기본 가이드

tr, sed, sd 명령어 비교

리눅스의 Init 시스템

Byung Kyu KIM

Helm

Helm Install

바이너리 다운로드

설치 Script 활용

Creating Your Own Charts

Chart directory 구조

Chart.yaml 수정

values.yaml 수정

templates/service.yaml 수정

helm lint : chart 파일 검사

helm template : kubernetes manifest 생성

helm install : chart 활용 kubernetes service install

helm upgrade, helm uninstall

Chart package, repository

helm package

Local repository directory

Github chart repository 활용

Repository 등록 및 설치

ConfigMap 적용

댓글남기기

참고

macOS Homebrew Cask, 추가 애플리케이션

모던 CMake 기본 가이드

tr, sed, sd 명령어 비교

리눅스의 Init 시스템

`Chart.yaml` 수정

`values.yaml` 수정

`templates/service.yaml` 수정

`helm lint` : chart 파일 검사

`helm template` : kubernetes manifest 생성

`helm install` : chart 활용 kubernetes service install

`helm upgrade`, `helm uninstall`

`helm package`