kubernetes使用（十八) helm工具--变量及版本更新

本文链接：https://blog.youkuaiyun.com/qq_42883074/article/details/113518956

通过传递参数，动态渲染模板，让yaml文件内容，动态传入参数

[root@k8s-master01 mychart]# ls
charts  Chart.yaml  templates  values.yaml
# 在chart有values.yaml文件，定义yaml文件全局变量

一. helm变量使用

#我们大部分部署的服务结构基本一样，不同之处大致分为几种
1. image
2. tag
3. label名称
4. port
5. replicas

1. 定义全局变量

[root@k8s-master01 ~]# cd mychart/
[root@k8s-master01 mychart]# ls
charts  Chart.yaml  templates  values.yaml
[root@k8s-master01 mychart]# pwd
/root/mychart

vim valume.yaml

replicaCount: 1        #副本数量
image: nginx           #镜像
tag: 1.16              #版本
label: nginx           #标签
port: 80               #端口

2. 编辑之前部署的yaml文件

#常见变量使用
{{ .Values.变量名称 }}   #在yaml文件中调用变量的方法
{{ .Release.Name }}   #因为每次的名称都不一样,获取当前实体的名称来使用

切换目录

[root@k8s-master01 mychart]# cd templates/
[root@k8s-master01 templates]# ls
deployment.yaml  service.yaml

修改yaml

cat > deployment.yaml <<EOF
apiVersion: apps/v1
kind: Deployment
metadata:
  creationTimestamp: null
  labels:
    app: {{ .Release.Name }}-deploy
  name: {{ .Release.Name }}-deploy  #helm install 时起的名称加-deply
spec:
  replicas: 1
  selector:
    matchLabels:
      app: {{ .Values.label }}
  strategy: {}
  template:
    metadata:
      creationTimestamp: null
      labels:
        app: {{ .Values.label }}
    spec:
      containers:
      - image: {{ .Values.image }}
        name: nginx
        resources: {}
status: {}
EOF


cat > service.yaml <<EOF
apiVersion: v1
kind: Service
metadata:
  creationTimestamp: null
  labels:
    app: web          
  name: {{ .Release.Name }}-svc
spec:
  ports:
  - port: {{ .Values.port }}
    protocol: TCP
    targetPort: {{ .Values.port }}
  selector:
    app: {{ .Values.label }}
  type: NodePort
status:
  loadBalancer: {}
EOF

测试语法

#回到mychart同级目录
cd ~

#测试
helm install web1 mychart/ --dry-run

NAME: web1
LAST DEPLOYED: Mon Feb  1 15:21:32 2021
NAMESPACE: default
STATUS: pending-install
REVISION: 1
TEST SUITE: None
HOOKS:
MANIFEST:
---
# Source: mychart/templates/service.yaml
apiVersion: v1
kind: Service
metadata:
  creationTimestamp: null
  labels:
    app: web          
  name: web1-svc
spec:
  ports:
  - port: 80
    protocol: TCP
    targetPort: 80
  selector:
    app: nginx
  type: NodePort
status:
  loadBalancer: {}
---
# Source: mychart/templates/deployment.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
  creationTimestamp: null
  labels:
    app: web1-deploy
  name: web1-deploy  #helm install 时起的名称加-deply
spec:
  replicas: 1
  selector:
    matchLabels:
      app: nginx
  strategy: {}
  template:
    metadata:
      creationTimestamp: null
      labels:
        app: nginx
    spec:
      containers:
      - image: nginx
        name: nginx
        resources: {}
status: {}

#返回语法正常

部署

[root@k8s-master01 ~]# helm install web1 mychart/
NAME: web1
LAST DEPLOYED: Mon Feb  1 15:22:58 2021
NAMESPACE: default
STATUS: deployed
REVISION: 1
TEST SUITE: None

[root@k8s-master01 ~]# helm list
NAME	NAMESPACE	REVISION	UPDATED                                	STATUS  	CHART        	APP VERSION
web1	default  	1       	2021-02-01 15:22:58.560611304 +0800 CST	deployed	mychart-0.1.0	1.16.0

那么什么是复用呢？我们来多创建几个

[root@k8s-master01 ~]# helm install web2 mychart/
NAME: web2
LAST DEPLOYED: Mon Feb  1 15:24:24 2021
NAMESPACE: default
STATUS: deployed
REVISION: 1
TEST SUITE: None
[root@k8s-master01 ~]# helm install web3 mychart/
NAME: web3
LAST DEPLOYED: Mon Feb  1 15:24:28 2021
NAMESPACE: default
STATUS: deployed
REVISION: 1
TEST SUITE: None


#我们在只需要修改创建的helm的管理名称，就可以创建多个相同的pod
[root@k8s-master01 ~]# helm list
NAME	NAMESPACE	REVISION	UPDATED                                	STATUS  	CHART        	APP VERSION
web1	default  	1       	2021-02-01 15:22:58.560611304 +0800 CST	deployed	mychart-0.1.0	1.16.0     
web2	default  	1       	2021-02-01 15:24:24.971268591 +0800 CST	deployed	mychart-0.1.0	1.16.0     
web3	default  	1       	2021-02-01 15:24:28.612617947 +0800 CST	deployed	mychart-0.1.0	1.16.0  

#每个都是一套独立的应用，互不影响

二. 更新部署的应用

1. 修改yaml

vi values.yaml

tag: 1.16  #修改为1.17版本

2.更新

helm upgrade -f values.yaml web1 ~/mychart/

Release "web1" has been upgraded. Happy Helming!
NAME: web1
LAST DEPLOYED: Mon Feb  1 15:55:48 2021
NAMESPACE: default
STATUS: deployed
REVISION: 2
TEST SUITE: None

查看

[root@k8s-master01 mychart]# helm list
NAME	NAMESPACE	REVISION	UPDATED                                	STATUS  	CHART        	APP VERSION
web1	default  	2       	2021-02-01 15:55:48.693513647 +0800 CST	deployed	mychart-0.1.0	1.16.0     
web2	default  	1       	2021-02-01 15:24:24.971268591 +0800 CST	deployed	mychart-0.1.0	1.16.0  

#可以看到REVISION变为了2

3. 回滚

helm rollback web1 1

查看

[root@k8s-master01 mychart]# helm list
NAME	NAMESPACE	REVISION	UPDATED                                	STATUS  	CHART        	APP VERSION
web1	default  	3       	2021-02-01 16:00:42.142226076 +0800 CST	deployed	mychart-0.1.0	1.16.0     
web2	default  	1       	2021-02-01 15:24:24.971268591 +0800 CST	deployed	mychart-0.1.0	1.16.0 


#版本变更为了3

#当你不清楚那个版本更新了什么，你可以根据历史记录查看

#查看第一版本
helm get all --revision 1 web1

NAME: web1
LAST DEPLOYED: Mon Feb  1 15:22:58 2021
NAMESPACE: default
STATUS: superseded
REVISION: 1
TEST SUITE: None
USER-SUPPLIED VALUES:
null

COMPUTED VALUES:
image: nginx
label: nginx
port: 80
replicaCount: 1
tag: 1.16

HOOKS:
MANIFEST:
---
# Source: mychart/templates/service.yaml
apiVersion: v1
kind: Service
metadata:
  creationTimestamp: null
  labels:
    app: web          
  name: web1-svc
spec:
  ports:
  - port: 80
    protocol: TCP
    targetPort: 80
  selector:
    app: nginx
  type: NodePort
status:
  loadBalancer: {}
---
# Source: mychart/templates/deployment.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
  creationTimestamp: null
  labels:
    app: web1-deploy
  name: web1-deploy  #helm install 时起的名称加-deply
spec:
  replicas: 1
  selector:
    matchLabels:
      app: nginx
  strategy: {}
  template:
    metadata:
      creationTimestamp: null
      labels:
        app: nginx
    spec:
      containers:
      - image: nginx
        name: nginx
        resources: {}
status: {}

查看第二版本

[root@k8s-master01 mychart]# helm get all --revision 2 web1
NAME: web1
LAST DEPLOYED: Mon Feb  1 15:55:48 2021
NAMESPACE: default
STATUS: superseded
REVISION: 2
TEST SUITE: None
USER-SUPPLIED VALUES:
image: nginx
label: nginx
port: 80
replicaCount: 1
tag: 1.17           #可以看到镜像的标签版本不同，由此来确认回退的版本

COMPUTED VALUES:
image: nginx
label: nginx
port: 80
replicaCount: 1
tag: 1.17

HOOKS:
MANIFEST:
---
# Source: mychart/templates/service.yaml
apiVersion: v1
kind: Service
metadata:
  creationTimestamp: null
  labels:
    app: web          
  name: web1-svc
spec:
  ports:
  - port: 80
    protocol: TCP
    targetPort: 80
  selector:
    app: nginx
  type: NodePort
status:
  loadBalancer: {}
---
# Source: mychart/templates/deployment.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
  creationTimestamp: null
  labels:
    app: web1-deploy
  name: web1-deploy  #helm install 时起的名称加-deply
spec:
  replicas: 1
  selector:
    matchLabels:
      app: nginx
  strategy: {}
  template:
    metadata:
      creationTimestamp: null
      labels:
        app: nginx
    spec:
      containers:
      - image: nginx
        name: nginx
        resources: {}
status: {}