一、资源清单-结构

    五大对象字段：
        1. apiVersion [接口组/版本]
        2. kind [资源类型]
        3. metadata [元数据]
        4. spec [规格/期望]
        5. status [状态]

1.1 [接口组/版本] group/apiVersion 
    * 例子: apiVersion: v1                                # pod
            apiVersion: apps/v1                           # deployment
            apiVersion: batch/v1                          # job
            apiVersion: networking.k8s.io/v1              # ingress
            apiVersion: rbac.authorization.k8s.io/v1      # rbac
    
    常见命令: 
    1、查看集群api版本命令: kubectl api-versions
        
        root@k8s-master:~# kubectl api-versions
            admissionregistration.k8s.io/v1
            apiextensions.k8s.io/v1
            apiregistration.k8s.io/v1
            apps/v1
            authentication.k8s.io/v1
            authorization.k8s.io/v1
            autoscaling/v1
            autoscaling/v2
            batch/v1
            certificates.k8s.io/v1
            coordination.k8s.io/v1
            crd.projectcalico.org/v1
            discovery.k8s.io/v1
            events.k8s.io/v1
            flowcontrol.apiserver.k8s.io/v1
            networking.k8s.io/v1
            node.k8s.io/v1
            policy/v1
            rbac.authorization.k8s.io/v1
            resource.k8s.io/v1
            scheduling.k8s.io/v1
            storage.k8s.io/v1
            v1

        [注意事项]: 
            1. group为空时, 直接使用v1表示
            2. group和version之间用/分隔
            3. v1表示默认的版本, 即 core/v1

    2、查看某个资源的api解释命令: kubectl explain <资源类型> [Deployment、ReplicaSet、DaemonSet、Job、CronJob]
        例子: kubectl explain Pod     

1.2 [资源类型] kind: List
    * 例子: kind: Pod
            kind: Deployment
            kind: Service
            kind: Ingress
            kind: ConfigMap
            kind: Secret
            kind: PersistentVolumeClaim
            kind: Namespace
            kind: Node
            kind: PersistentVolume
            kind: ClusterRole
            kind: ClusterRoleBinding
            kind: CustomResourceDefinition
            kind: HPA
            kind: PodTemplate
            kind: LimitRange

1.3 [元数据] metadata:
    * 例子: metadata:
                name: my-pod
                namespace: default
                labels:
                    app: my-app
                annotations:
                    description: "This is my pod"

1.4 [规格/期望] spec:
    * 例子: 
    spec:
      containers:
        - name: my-container
          image: nginx:latest
          ports:
            - containerPort: 80
      replicas: 3
      selector:
        matchLabels:
          app: my-app
      volumeMounts:
        - name: my-volume
          mountPath: /data
      volumes:
        - name: my-volume
          persistentVolumeClaim:
            claimName: my-pvc

1.5 [状态] status: # 初次自定义时, 一般不写该字段, 由系统自动生成和维护
    * 例子: 
    status:
      coordinations:
        leaseDurationSeconds: 15
        renewTime: "2023-10-01T12:00:00Z"



# =======================================================================



二、pod 资源清单示例：
# 1. 创建一个名为 my-pod 的 Pod，包含两个容器 第一个容器使用 nginx 镜像，监听 80 端口, 第二个容器使用 busybox 镜像, 执行一个简单的命令 Pod 运行在 default 命名空间: 
 vim my-pod.yaml

  apiVersion: v1
  kind: Pod
  metadata:
    name: my-pod
    namespace: default
    labels:
      app: my-app
    annotations:
      description: "This is my pod"
  spec:
    containers:
      - name: my-container
        image: nginx:latest
        ports:
          - containerPort: 80
      - name: sidecar-container
        image: busybox
        command:
          - "bash/sh"
          - "-c"
          - "sleep 3600"
    replicas: 3
    selector:
      matchLabels:
        app: my-app
    volumeMounts:
      - name: my-volume
        mountPath: /data
    volumes:
      - name: my-volume
        persistentVolumeClaim:
          claimName: my-pvc

2、pod 资源清单应用命令: (实例化资源对象)
    kubectl apply -f my-pod.yaml

3、查看 pod 资源命令:
    kubectl get pods -A                  # 查看所有命名空间的 pod
    kubectl get pods -n default          # 查看 default 命名空间的 pod
    kubectl get pods -n kube-system      # 查看 kube-system 命名空间的 pod
    kubectl get pod my-pod -o yaml       # 查看指定 pod 的详细信息
    kubectl get pod my-pod -o wide       # 查看指定 pod 的宽表信息(IP、节点等)