kubernetes 使用jq命令对资源配置查看

有图形化的直接从图形化可以看到各种资源，如Deployment、Pod等资源的配置

这里写一个 jq 命令

jq命令允许针对json进行操作，如过滤

jq命令centos环境下安装

# yum -y install jq

假设我们有个文件

# cat pod-yaml

{
    "apiVersion": "v1",
    "kind": "Pod",
    "metadata": {
        "name": "nginx-pod",
        "namespace": "default"
    },
    "spec": {
        "containers": [
            {
                "image": "nginx:1.20",
                "imagePullPolicy": "IfNotPresent",
                "name": "nginx-pod",
                "resources": {
                    "limits": {
                        "cpu": "20m",
                        "memory": "120Mi"
                    },
                    "requests": {
                        "cpu": "10m",
                        "memory": "100Mi"
                    }
                }
            }
        ]
    }
}

我们要直接取出下面这一段

  "limits": {
    "cpu": "20m",
    "memory": "120Mi"
  },
  "requests": {
    "cpu": "10m",
    "memory": "100Mi"
  }

可以这么执行

# cat pod-yaml | jq .spec.containers[].resources

输出：
{
  "limits": {
    "cpu": "20m",
    "memory": "120Mi"
  },
  "requests": {
    "cpu": "10m",
    "memory": "100Mi"
  }
}

规律很容易看出来，就是取key的value

同样，在查看资源时也可以这样使用

例如查看一个pod资源限制：

查看pod名称
# kubectl get pod
NAME        READY   STATUS    RESTARTS   AGE
nginx-pod   1/1     Running   0          22s


查看该pod的资源限制
# kubectl get pod/nginx-pod -o json | jq .spec.containers[].resources
{
  "limits": {
    "cpu": "20m",
    "memory": "120Mi"
  },
  "requests": {
    "cpu": "10m",
    "memory": "100Mi"
  }
}


查看该Pod的容器重启策略
# kubectl get pod/nginx-pod -o json | jq .spec.restartPolicy
"Always"