自定义资源CRD使用介绍

apiVersion: apiextensions.k8s.io/v1
kind: CustomResourceDefinition
metadata:
  # name 必须匹配下面的spec字段：<plural>.<group>  
  name: foos.crd.example.com
  # for more information on the below annotation, please see
  # https://github.com/kubernetes/enhancements/blob/master/keps/sig-api-machinery/2337-k8s.io-group-protection/README.md
  annotations:
    "api-approved.kubernetes.io": "unapproved, experimental-only; please get an approval from Kubernetes API reviewers if you're trying to develop a CRD in the *.k8s.io or *.kubernetes.io groups"
spec:
  # group 名用于 REST API 中的定义： /apis/<group>/<version>
  group: crd.example.com
  # 列出自定义资源的所有 API 版本
  versions:
    - name: v1  # 版本名称，比如v1，v1beta1
      served: true  # 是否开启通过 REST APIs访问 `/apis/<group>/<version>/...`
      storage: true # 必须将一个且只有一个版本标记为存储版本
      schema: # 定义自定义对象的声明规范
        # schema used for validation
        openAPIV3Schema:
          type: object
          properties:
            spec:
              type: object
              properties:
                deploymentName:
                  type: string
                replicas:
                  type: integer
                  minimum: 1
                  maximum: 10
            status:
              type: object
              properties:
                availableReplicas:
                  type: integer
  names:
    # kind 是 sigular 的一个驼峰形式的定义，在资源清单中会使用
    kind: Foo
    # plural 名字用于 REST API 中的定义：/apis/<group>/<version>/<plural>    
    plural: foos
    # singular 名称用于 CLI 操作或显示的一个别名    
    singular: foo
    # shortNames 相当于缩写形式    
    shortNames:
    - fo
  scope: Namespaced

$  kubectl apply -f crd.example.com_foos.yaml 
customresourcedefinition.apiextensions.k8s.io/foos.crd.example.com created

$ kubectl get crd | grep example
foos.crd.example.com                                  2022-05-11T05:28:51Z

/apis/crd/example.com/v1/namespaces/*/foos/...

apiVersion: crd.example.com/v1
kind: Foo
metadata:
  name: example-foo
spec:
  deploymentName: example-foo
  replicas: 1

kubectl get foo
NAME          AGE
example-foo   20m

kubectl get foo example-foo -o yaml
apiVersion: crd.example.com/v1
kind: Foo
metadata:
  annotations:
    kubectl.kubernetes.io/last-applied-configuration: |
      {"apiVersion":"crd.example.com/v1","kind":"Foo","metadata":{"annotations":{},"name":"example-foo","namespace":"default"},"spec":{"deploymentName":"example-foo","replicas":1}}
  creationTimestamp: "2022-05-11T05:40:38Z"
  generation: 1
  name: example-foo
  namespace: default
  resourceVersion: "37605212"
  uid: 56d5b1d3-f6f9-4106-90c4-a0e3c7d130c0
spec:
  deploymentName: example-foo
  replicas: 1