目录
一、release介绍
在以上的章节中曾介绍过 helm 的两大术语：chart 和 release。如果可以把 chart 比作程序源码的话，那么 release 则可以看做是程序运行时的进程。
chart 是用户可直接感知的对象（其表现形式就是 .tgz 格式的压缩包）；而 release 理解起来则比较抽象，它是专属于 helm 的一个逻辑概念，用来标识在 k8s 中运行的一组资源。有了 release，helm 在操作 k8s 时，就再也不用逐个管理资源，而可以将一组相关的资源当做一个整体来操作，比如删除或升级。
二、release 查看
$ helm ls
NAME NAMESPACE REVISION UPDATED STATUS CHART APP VERSION
三、release 安装
在线安装指定的 chart，比如 nginx-ingress。
$ helm repo add nginx-stable https://helm.nginx.com/stable
$ helm repo update
$ helm search repo nginx-ingress
NAME CHART VERSION APP VERSION DESCRIPTION
aliyun/nginx-ingress 0.9.5 0.10.2 An nginx Ingress controller that uses ConfigMap...
nginx-stable/nginx-ingress 0.9.3 1.11.3 NGINX Ingress Controller
stable/nginx-ingress 1.41.3 v0.34.1 DEPRECATED! An nginx Ingress controller that us...
aliyun/nginx-lego 0.3.1 Chart for nginx-ingress-controller and kube-lego
stable/nginx-lego 0.3.1 Chart for nginx-ingress-controller and kube-lego
$ helm install mynginx-ingress nginx-stable/nginx-ingress
NAME: mynginx-ingress
LAST DEPLOYED: Sat Jun 12 16:17:57 2021
NAMESPACE: default
STATUS: deployed
REVISION: 1
TEST SUITE: None
NOTES:
The NGINX Ingress Controller has been installed.
四、release更新
如果想修改运行时 release 的配置，可以使用 --set 或者 -f 选项进行修改。
4.1 基于命令行更新 release
# mynginx-ingress 是上面创建的 release 名；nginx-stable/nginx-ingress 是在线 chart 名
$ helm upgrade --set controller.hostNetwork=true mynginx-ingress nginx-stable/nginx-ingress
Release "mynginx-ingress" has been upgraded. Happy Helming!
NAME: mynginx-ingress
LAST DEPLOYED: Sat Jun 12 16:20:05 2021
NAMESPACE: default
STATUS: deployed
REVISION: 2
TEST SUITE: None
NOTES:
The NGINX Ingress Controller has been installed.
4.2 基于文件更新 release
如果想基于文件来更新 release，则首先需要将 chart 下载到本地，然后手动修改 chart 的 values.yaml 文件。
$ helm pull nginx-stable/nginx-ingress
# 下载 chart
$ tar zxf nginx-ingress-0.9.3.tgz
# 解压缩 chart
$ sed -i 's/hostNetwork: false/hostNetwork: true/g' nginx-ingress/values.yaml
# 修改 values.yaml 内容。比如修改 hostNetwork 的值为 true
$ helm upgrade mynginx-ingress nginx-ingress -f nginx-ingress/values.yaml
Release "mynginx-ingress" has been upgraded. Happy Helming!
NAME: mynginx-ingress
LAST DEPLOYED: Sat Jun 12 16:23:50 2021
NAMESPACE: default
STATUS: deployed
REVISION: 3
TEST SUITE: None
NOTES:
The NGINX Ingress Controller has been installed.
4.3 查看 release 更新后的新值
$ helm get values mynginx-ingress
五、release 版本
$ helm history mynginx-ingress
# mynginx-ingress 这个 release 各个历史版本。其中 REVISION 3 是最新的版本。
REVISION UPDATED STATUS CHART APP VERSION DESCRIPTION
1 Sat Jun 12 16:17:57 2021 superseded nginx-ingress-0.9.3 1.11.3 Install complete
2 Sat Jun 12 16:20:05 2021 superseded nginx-ingress-0.9.3 1.11.3 Upgrade complete
3 Sat Jun 12 16:23:50 2021 deployed nginx-ingress-0.9.3 1.11.3 Upgrade complete
六、release 回滚
$ helm rollback mynginx-ingress 1
Rollback was a success! Happy Helming!
$ helm history mynginx-ingress
REVISION UPDATED STATUS CHART APP VERSION DESCRIPTION
1 Sat Jun 12 16:17:57 2021 superseded nginx-ingress-0.9.3 1.11.3 Install complete
2 Sat Jun 12 16:20:05 2021 superseded nginx-ingress-0.9.3 1.11.3 Upgrade complete
3 Sat Jun 12 16:23:50 2021 superseded nginx-ingress-0.9.3 1.11.3 Upgrade complete
4 Sat Jun 12 16:29:59 2021 deployed nginx-ingress-0.9.3 1.11.3 Rollback to 1
七、release 卸载
$ helm uninstall mynginx-ingress
release "mynginx-ingress" uninstalled