目錄

一.創(chuàng)建helm chart（以nginx為例）

1.通過create去創(chuàng)建模板

2.查看模板下的文件

3.用chart模版安裝nginx

二.版本更新和回滾問題

1.使用upgrade -f values.yaml或者命令行--set來設置

2.查看歷史版本并回滾

三.helm模板內管道和函數

1.defautl

2.quote

3.indent和nindent

4.upper

5.title

6.toYaml

---

上一篇文章說到，我們可以通過helm將眾多已經初步配置好的yaml文件下載來整合使用，甚至還可以自己定義好需要的安裝參數用于下載完成后直接使用而不需要過多更改，現在仍然可以在這些功能上繼續(xù)推進。創(chuàng)建helm chart模板，現成的yaml文件，自己只需要更改values變量文件即可，如下：

一.創(chuàng)建helm chart（以nginx為例）

1.通過create去創(chuàng)建模板

[root@k8s-master helm]# helm create nginx  #創(chuàng)建完成后會在本地創(chuàng)建一個nginx目錄
drwxr-xr-x 4 root ?  root ? ? ? ? 93 Mar 18 19:58 nginx
[root@k8s-master helm]# tree nginx
nginx
├── charts ? #存放的依賴的子chart
├── Chart.yaml ? ? #存放chart基本信息的文件 
├── templates ? ? #模板，名稱都簡單翻譯一下就懂存的是什么
│?? ├── deployment.yaml
│?? ├── _helpers.tpl ? #模板助手
│?? ├── hpa.yaml ? ?
│?? ├── ingress.yaml
│?? ├── NOTES.txt ? #本chart的幫助信息
│?? ├── serviceaccount.yaml
│?? ├── service.yaml
│?? └── tests
│?? ? ? └── test-connection.yaml
└── values.yaml ? #存儲的是你在的templates中文件需要用到的變量
?
3 directories, 10 files

2.查看模板下的文件

[root@k8s-master helm]# cat nginx/templates/service.yaml 
apiVersion: v1
kind: Service
metadata:name: {{ include "nginx.fullname" . }} ?  #這些使用{{}}括起來的變量就是你需要在values.yaml文件中用值替換的變量labels:{{- include "nginx.labels" . | nindent 4 }}
spec:type: {{ .Values.service.type }}ports:- port: {{ .Values.service.port }}targetPort: httpprotocol: TCPname: httpselector:{{- include "nginx.selectorLabels" . | nindent 4 }}
?

3.用chart模版安裝nginx

（1）在values.yaml中定義變量，如下是nginx模版的原始文件

[root@k8s-master nginx]# cat values.yaml 
# Default values for nginx.
# This is a YAML-formatted file.
# Declare variables to be passed into your templates.
?
replicaCount: 1
?
image:repository: nginx ?  #找到需要的地方，這里是鏡像名pullPolicy: IfNotPresent ? #鏡像拉取策略# Overrides the image tag whose default is the chart appVersion.tag: "" ?  #版本信息
?
imagePullSecrets: []
nameOverride: ""
fullnameOverride: ""
?
serviceAccount:# Specifies whether a service account should be createdcreate: true# Annotations to add to the service accountannotations: {}# The name of the service account to use.# If not set and create is true, a name is generated using the fullname templatename: ""
?
podAnnotations: {}
?
podSecurityContext: {}# fsGroup: 2000
?
securityContext: {}# capabilities:# ? drop:# ? - ALL# readOnlyRootFilesystem: true# runAsNonRoot: true# runAsUser: 1000
?
service: ?  #service類型和端口type: ClusterIPport: 80
?
ingress: ? #ingress的相關配置enabled: falseclassName: ""annotations: {}# kubernetes.io/ingress.class: nginx# kubernetes.io/tls-acme: "true"hosts:- host: chart-example.localpaths:- path: /pathType: ImplementationSpecifictls: []#  - secretName: chart-example-tls# ?  hosts:# ? ?  - chart-example.local
?
resources: {} ?  #資源要求# 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
?
autoscaling:enabled: falseminReplicas: 1maxReplicas: 100targetCPUUtilizationPercentage: 80# targetMemoryUtilizationPercentage: 80
?
nodeSelector: {}
?
tolerations: []
?
affinity: {}

（2）配置后的values.yaml

[root@k8s-master helm]# cat nginx/values.yaml 
# Default values for nginx.
# This is a YAML-formatted file.
# Declare variables to be passed into your templates.
?
replicaCount: 1
?
image:repository: nginxpullPolicy: IfNotPresent# Overrides the image tag whose default is the chart appVersion.tag: "1.17.3" ? #版本為1.17.3?
imagePullSecrets: []
nameOverride: ""
fullnameOverride: ""
?
serviceAccount:# Specifies whether a service account should be createdcreate: true# Annotations to add to the service accountannotations: {}# The name of the service account to use.# If not set and create is true, a name is generated using the fullname templatename: ""
?
podAnnotations: {}
?
podSecurityContext: {}# fsGroup: 2000
?
securityContext: {}# capabilities:# ? drop:# ? - ALL# readOnlyRootFilesystem: true# runAsNonRoot: true# runAsUser: 1000
?
service:type: NodePort ?  #NodePort類型port: 80 ? ? #80端口
?
ingress:enabled: falseclassName: ""annotations: {}# kubernetes.io/ingress.class: nginx# kubernetes.io/tls-acme: "true"hosts:- host: chart-example.localpaths:- path: /pathType: ImplementationSpecifictls: []#  - secretName: chart-example-tls# ?  hosts:# ? ?  - chart-example.local
?
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
?
autoscaling:enabled: falseminReplicas: 1maxReplicas: 100targetCPUUtilizationPercentage: 80# targetMemoryUtilizationPercentage: 80
?
nodeSelector: {}
?
tolerations: []
?
affinity: {}

（3）安裝命令

同k8s運行pod差不多，都可以先測試一下但不實際運行helm install --dry-run my-nginx nginx/，卸載將install替換為uninstall即可

[root@k8s-master helm]# helm install my-nginx nginx/
#指定好安裝后的名稱后要指定這個nginx模版目錄，安裝完成后還會提示你訪問方式
NAME: my-nginx
LAST DEPLOYED: Mon Mar 18 20:27:00 2024
NAMESPACE: default
STATUS: deployed
REVISION: 1
NOTES:
1. Get the application URL by running these commands:export NODE_PORT=$(kubectl get --namespace default -o jsonpath="{.spec.ports[0].nodePort}" services my-nginx)export NODE_IP=$(kubectl get nodes --namespace default -o jsonpath="{.items[0].status.addresses[0].address}")echo http://$NODE_IP:$NODE_PORT[root@k8s-master helm]# kubectl  get pods,svc
NAME ? ? ? ? ? ? ? ? ? ? ? ? ? READY ? STATUS ?  RESTARTS ? AGE
pod/my-nginx-9d774fb48-94wd8 ? 1/1 ? ? Running ? 0 ? ? ? ?  3m29s
?
NAME ? ? ? ? ? ? ? ? TYPE ? ? ?  CLUSTER-IP ? ?  EXTERNAL-IP ? PORT(S) ? ? ?  AGE
service/kubernetes ? ClusterIP ? 10.96.0.1 ? ? ? <none> ? ? ?  443/TCP ? ? ?  90m
service/my-nginx ? ? NodePort ?  10.97.171.192 ? <none> ? ? ?  80:30140/TCP ? 3m29s
[root@k8s-master helm]# curl http://192.168.2.151:30140
<!DOCTYPE html>
<html>
<head>
<title>Welcome to nginx!</title>
<style>body {width: 35em;margin: 0 auto;font-family: Tahoma, Verdana, Arial, sans-serif;}
</style>
</head>
<body>
<h1>Welcome to nginx!</h1>
<p>If you see this page, the nginx web server is successfully installed and
working. Further configuration is required.</p>
?
<p>For online documentation and support please refer to
<a href="http://nginx.org/">nginx.org</a>.<br/>
Commercial support is available at
<a href="http://nginx.com/">nginx.com</a>.</p>
?
<p><em>Thank you for using nginx.</em></p>
</body>
</html>

二.版本更新和回滾問題

1.使用upgrade -f values.yaml或者命令行--set來設置

[root@k8s-master helm]# kubectl  describe pod my-nginx-9d774fb48-94wd8 | grep ImageImage: ? ? ? ?  nginx:1.17.5Image ID: ? ? ? docker.io/library/nginx@sha256:922c815aa4df050d4df476e92daed4231f466acc8ee90e0e774951b0fd7195a4
[root@k8s-master helm]# vim nginx/values.yaml 
[root@k8s-master helm]# vim nginx/values.yaml 
[root@k8s-master helm]# helm upgrade -f nginx/values.yaml my-nginx nginx/
Release "my-nginx" has been upgraded. Happy Helming!
NAME: my-nginx
LAST DEPLOYED: Mon Mar 18 20:35:40 2024
NAMESPACE: default
STATUS: deployed
REVISION: 2
NOTES:
1. Get the application URL by running these commands:export NODE_PORT=$(kubectl get --namespace default -o jsonpath="{.spec.ports[0].nodePort}" services my-nginx)export NODE_IP=$(kubectl get nodes --namespace default -o jsonpath="{.items[0].status.addresses[0].address}")echo http://$NODE_IP:$NODE_PORT
[root@k8s-master helm]# kubectl  get pods
NAME ? ? ? ? ? ? ? ? ? ? ?  READY ? STATUS ? ? ? ? ? ?  RESTARTS ? AGE
my-nginx-698cb48f59-v4pbb ? 0/1 ? ? ContainerCreating ? 0 ? ? ? ?  7s
my-nginx-9d774fb48-94wd8 ?  1/1 ? ? Running ? ? ? ? ? ? 0 ? ? ? ?  8m48s
[root@k8s-master helm]# kubectl  get pods
NAME ? ? ? ? ? ? ? ? ? ? ?  READY ? STATUS ?  RESTARTS ? AGE
my-nginx-698cb48f59-v4pbb ? 1/1 ? ? Running ? 0 ? ? ? ?  64s
[root@k8s-master helm]# kubectl  describe pod my-nginx-698cb48f59-v4pbb | grep ImageImage: ? ? ? ?  nginx:1.17.8Image ID: ? ? ? docker.io/library/nginx@sha256:380eb808e2a3b0dd954f92c1cae2f845e6558a15037efefcabc5b4e03d666d03

2.查看歷史版本并回滾

[root@k8s-master helm]# helm history my-nginx
REVISION    UPDATED ? ? ? ? ? ? ? ?     STATUS ?    CHART ? ?   APP VERSION DESCRIPTION ? ? 
1 ? ? ?     Mon Mar 18 20:27:00 2024    superseded  nginx-0.1.0 1.16.0 ? ?  Install complete
2 ? ? ?     Mon Mar 18 20:35:40 2024    deployed    nginx-0.1.0 1.16.0 ? ?  Upgrade complete
?
[root@k8s-master helm]# helm rollback my-nginx 1
Rollback was a success! Happy Helming!
[root@k8s-master helm]# kubectl get pods
NAME ? ? ? ? ? ? ? ? ? ? ? READY ? STATUS ?  RESTARTS ? AGE
my-nginx-9d774fb48-9pv7q ? 1/1 ? ? Running ? 0 ? ? ? ?  5s
[root@k8s-master helm]# kubectl  describe pods my-nginx-9d774fb48-9pv7q | grep ImageImage: ? ? ? ?  nginx:1.17.5Image ID: ? ? ? docker.io/library/nginx@sha256:922c815aa4df050d4df476e92daed4231f466acc8ee90e0e774951b0fd7195a4

三.helm模板內管道和函數

1.defautl

也就是和管道符號配合，當你values中的值未指定時，就使用此默認值

以nginx模版的port為例，將其設置為空，但設置了默認值為80，創(chuàng)建過后仍然會暴露80端口

[root@k8s-master helm]# cat nginx/values.yaml | grep portport: 
#在deployment文件中引用了此變量的地方設置default
[root@k8s-master helm]# cat nginx/templates/deployment.yaml  | grep defaultimage: "{{ .Values.image.repository }}:{{ .Values.image.tag | default .Chart.AppVersion }}"containerPort: {{ .Values.service.port | default 80 }} ? #這樣寫#在service文件中引用了此變量的地方設置default
[root@k8s-master helm]# cat nginx/templates/service.yaml | grep default- port: {{ .Values.service.port | default 80 }}
[root@k8s-master helm]# helm install nginx nginx/
[root@k8s-master helm]# kubectl get pods,svc
NAME ? ? ? ? ? ? ? ? ? ? ? ? READY ? STATUS ?  RESTARTS ? AGE
pod/nginx-6467995c7d-gt4g5 ? 1/1 ? ? Running ? 0 ? ? ? ?  8s
?
NAME ? ? ? ? ? ? ? ? TYPE ? ? ?  CLUSTER-IP ? ?  EXTERNAL-IP ? PORT(S) ? ? ?  AGE
service/kubernetes ? ClusterIP ? 10.96.0.1 ? ? ? <none> ? ? ?  443/TCP ? ? ?  113m
service/nginx ? ? ?  NodePort ?  10.106.164.22 ? <none> ? ? ?  80:32598/TCP ? 8s

2.quote

這個表示的是為某個變量設置后，無論設定的變量值是什么類型，都將其識別為字符串類型，書寫格式如下

{{ quote .Values.service.port }}

3.indent和nindent

indent表示在同一行變量值前設定多少個縮進值，nindent表示換行后再在變量值前設置多少個縮進值，書寫格式如下

{{ .Values.service.port | indent/nindent 10 }}

4.upper

將值都變?yōu)榇髮?#xff0c;格式如下

{{ upper .Values.service.port }}

5.title

將首字母設置為大寫，格式如下

{{ title .Values.service.port }}

6.toYaml

將一整個yaml塊都取值取過來，一般還需要陪著縮進一起使用，格式如下

{{ toYaml .Values.service.port | indent/nindent 10 }}