Helm学习

1. 安装helm

    # 官方一键安装脚本
    curl https://raw.githubusercontent.com/helm/helm/master/scripts/get > get_helm.sh
    $ chmod 700 get_helm.sh
    $ ./get_helm.sh

2. 安装Tiller

   1. 先在 K8S 集群上每个节点安装 socat 软件(yum install -y socat)，否则会报错

       E0522 22:22:15.492436   24409 portforward.go:331] an error occurred forwarding 38398 -> 44134: error forwarding port 44134 to pod dc6da4ab99ad9c497c0cef1776b9dd18e0a612d507e2746ed63d36ef40f30174, uid : unable to do port forwarding: socat not found.
       Error: cannot connect to Tiller

   2. 国内安装使用阿里云的镜像，Google被墙

       helm init --service-account tiller --upgrade -i registry.cn-hangzhou.aliyuncs.com/google_containers/tiller:v2.13.1

   3. 查看所有的仓库

       [root@k8s-master home]# helm repo list
       NAME         URL                                             
       stable       https://kubernetes-charts.storage.googleapis.com
       local        http://127.0.0.1:8879/charts

   4. 添加harbor的charts仓库

       helm repo add --username helm --password Helm12345 home-helm http://home.lodsve.com:9013/chartrepo/helm

   5. 更新仓库

       helm repo update

   6. 给 Tiller 授权

      1. 创建service account

          kubectl create serviceaccount --namespace kube-system tiller
          kubectl create clusterrolebinding tiller-cluster-rule --clusterrole=cluster-admin --serviceaccount=kube-system:tiller

      2. 授权

          kubectl patch deploy --namespace kube-system tiller-deploy -p '{"spec":{"template":{"spec":{"serviceAccount":"tiller"}}}}'

      3. 验证是否成功

          [root@k8s-master home]# kubectl get deploy --namespace kube-system tiller-deploy --output yaml | grep serviceAccount
                serviceAccount: tiller
                serviceAccountName: tiller

   7. 卸载

       helm reset或者helm reset --force

3. 创建charts

   1. 创建名为csc-fmis-config-server的chart

       helm create csc-fmis-config-server

   2. 编辑各种文件：

       [root@k8s-master workspace]# tree csc-fmis-config-server/
       csc-fmis-config-server/
       ├── Chart.yaml                      # Chart本身的版本和配置信息
       ├── charts                          # 依赖的chart
       ├── README.md                       # readme
       ├── templates                       # 配置模板目录
       │   ├── NOTES.txt                   # helm提示信息
       │   ├── _helpers.tpl                # 用于修改kubernetes objcet配置的模板
       │   ├── deployment.yaml             # k8s的部署yaml
       │   └── service.yaml                # k8s的服务yaml
       └── values.yaml                     # 上面模板中使用到的值
      
       2 directory, 7 files

   3. 使用go的template语法

   4. 检查配置和模板是否有效

       helm install --dry-run --debug csc-fmis-config-server -f custom.yaml

   5. 可以使用外部yaml文件覆盖charts内部的values.yaml中的值，类似spring-boot中的application.yml一样

4. 推送到远端helm charts repo

   1. 安装helm插件，以支持helm push

       helm plugin install https://github.com/chartmuseum/helm-push

   2. helm push

       helm push csc-fmis-config-server/ --version="0.1.2" home-helm

   3. push语法

       $ helm push mychart-0.1.0.tgz chartmuseum       # push .tgz from "helm package"
       $ helm push . chartmuseum                       # package and push chart directory
       $ helm push . --version="7c4d121" chartmuseum   # override version in Chart.yaml
       $ helm push . https://my.chart.repo.com         # push directly to chart repo URL

5. 安装到k8s中

   1. helm install csc-fmis-config-server
   2. helm install csc-fmis-config-server -f custom.yaml
   3. helm install csc-fmis-config-server --set foo=bar --set foo=newbar
   4. helm install --help查看其它用法
   5. helm list