Helm系列(二) 自创建Chart

一、配置Chart

之前的Chart是通过从设置的仓库中拉取，那么如何自定义Chart呢？

1、创建Chart

[root@k8smaster ~]# helm create mychart
Creating mychart
[root@k8smaster ~]# ll mychart/
总用量 8
drwxr-xr-x 2 root root    6 6月  27 23:58 charts
-rw-r--r-- 1 root root 1143 6月  27 23:58 Chart.yaml
drwxr-xr-x 3 root root  162 6月  27 23:58 templates
-rw-r--r-- 1 root root 1874 6月  27 23:58 values.yaml

• Chart.yaml 当前Chart属性配置信息
• templates 自定义yaml文件存放的目录
• values.yaml 全局变量定义的文件

2、自定义yaml文件

再templates目录中新建两个yaml文件：

• deployment.yaml
• service.yaml

上面中的通过helm create创建了模板，里面已经有两个文件，如果自己的deployment，可以进行替换。

deployment.yaml文件：

apiVersion: apps/v1
kind: Deployment
metadata:
  name: {{ include "mychart.fullname" . }}
  labels:
    {{- include "mychart.labels" . | nindent 4 }}
spec:
  {{- if not .Values.autoscaling.enabled }}
  replicas: {{ .Values.replicaCount }}
  {{- end }}
  selector:
    matchLabels:
      {{- include "mychart.selectorLabels" . | nindent 6 }}
  template:
    metadata:
      {{- with .Values.podAnnotations }}
      annotations:
        {{- toYaml . | nindent 8 }}
      {{- end }}
      labels:
        {{- include "mychart.selectorLabels" . | nindent 8 }}
    spec:
      {{- with .Values.imagePullSecrets }}
      imagePullSecrets:
        {{- toYaml . | nindent 8 }}
      {{- end }}
      serviceAccountName: {{ include "mychart.serviceAccountName" . }}
      securityContext:
        {{- toYaml .Values.podSecurityContext | nindent 8 }}
      containers:
        - name: {{ .Chart.Name }}
          securityContext:
            {{- toYaml .Values.securityContext | nindent 12 }}
          image: "{{ .Values.image.repository }}:{{ .Values.image.tag | default .Chart.AppVersion }}"
          imagePullPolicy: {{ .Values.image.pullPolicy }}
          ports:
            - name: http
              containerPort: 80
              protocol: TCP
          livenessProbe:
            httpGet:
              path: /
              port: http
          readinessProbe:
            httpGet:
              path: /
              port: http
          resources:
            {{- toYaml .Values.resources | nindent 12 }}
      {{- with .Values.nodeSelector }}
      nodeSelector:
        {{- toYaml . | nindent 8 }}
      {{- end }}
      {{- with .Values.affinity }}
      affinity:
        {{- toYaml . | nindent 8 }}
      {{- end }}
      {{- with .Values.tolerations }}
      tolerations:
        {{- toYaml . | nindent 8 }}
      {{- end }}

service.yaml文件：

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

可以看到上面两个文件中一些变量是以 {{ }} 进行书写，而这些文件中变量来自于values.yaml文件中：

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

replicaCount: 1

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

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

serviceAccount:
  # Specifies whether a service account should be created
  create: true
  # Annotations to add to the service account
  annotations: {}
  # The name of the service account to use.
  # If not set and create is true, a name is generated using the fullname template
  name: ""

podAnnotations: {}

podSecurityContext: {}
  # fsGroup: 2000

securityContext: {}
  # capabilities:
  #   drop:
  #   - ALL
  # readOnlyRootFilesystem: true
  # runAsNonRoot: true
  # runAsUser: 1000

service:
  type: NodePort
  port: 80

ingress:
  enabled: false
  className: ""
  annotations: {}
    # kubernetes.io/ingress.class: nginx
    # kubernetes.io/tls-acme: "true"
  hosts:
    - host: chart-example.local
      paths:
        - path: /
          pathType: ImplementationSpecific
  tls: []
  #  - 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: false
  minReplicas: 1
  maxReplicas: 100
  targetCPUUtilizationPercentage: 80
  # targetMemoryUtilizationPercentage: 80

nodeSelector: {}

tolerations: []

affinity: {}

所以如果需要部署不同的deployment.yaml，只需要修改values.yaml文件中的变量，这样也就进行了yaml文件的复用。values.yaml文件中可以定义这几个变量，一般这是不同的：

• image
• tag
• label
• port
• replicas

二、安装Chart

[root@k8smaster ~]# helm install web mychart
NAME: web
LAST DEPLOYED: Mon Jun 28 00:47:03 2021
NAMESPACE: default
STATUS: deployed
REVISION: 1
...

查看Service：

[root@k8smaster ~]# kubectl get svc
NAME           TYPE        CLUSTER-IP     EXTERNAL-IP   PORT(S)        AGE
kubernetes     ClusterIP   10.96.0.1      <none>        443/TCP        2m55s
web2-mychart   NodePort    10.108.84.36   <none>        80:31334/TCP   9s