通过命令行使用 API

  长话短说，我们将使用以 batch API 组为例来讲 cli 相关的操作。

  首先，需要在终端运行下面的命令：

[root@localhost ~]#  kubectl proxy --port=8089
Starting to serve on 127.0.0.1:8089

　　这个命令把 kubernetes API 服务代理到了本地，并处理了有关身份认证和授权相关的逻辑。这样我们就可以直接使用 HTTP 来发送请求，并接收返回的 JSON 数据。再打开一个终端，尝试查询下 v1：

[root@localhost ~]# curl http://127.0.0.1:8089/apis/batch/v1
{
  "kind": "APIResourceList",
  "apiVersion": "v1",
  "groupVersion": "batch/v1",
  "resources": [
    {
      "name": "jobs",
      "singularName": "",
      "namespaced": true,
      "kind": "Job",
      "verbs": [
        "create",
        "delete",
        "deletecollection",
        "get",
        "list",
        "patch",
        "update",
        "watch"
      ],
      "categories": [
        "all"
      ],
      "storageVersionHash": "mudhfqk/qZY="
    },
    {
      "name": "jobs/status",
      "singularName": "",
      "namespaced": true,
      "kind": "Job",
      "verbs": [
        "get",
        "patch",
        "update"
      ]
    }
  ]
}

　　也不是必须要使用 curl  和 kubectl proxy 命令才能访问 kubernetes 的 HTTP API，还可以使用 kubectl  get  --raw 命令，比如 curl http://127.0.0.1:8089/apis/batch/v1 改为 kubectl get --raw /apis/batch/v1。

[root@localhost ~]# kubectl get --raw /apis/batch/v1
{"kind":"APIResourceList","apiVersion":"v1","groupVersion":"batch/v1","resources":[{"name":"jobs","singularName":"","namespaced":true,"kind":"Job","verbs":["create","delete","deletecollection","get","list","patch","update","watch"],"categories":["all"],"storageVersionHash":"mudhfqk/qZY="},{"name":"jobs/status","singularName":"","namespaced":true,"kind":"Job","verbs":["get","patch","update"]}]}