警告: 有用的预警

kubectl get --raw /metrics | prom2json | jq '
  .[] | select(.name=="apiserver_requested_deprecated_apis").metrics[].labels
'

{
  "group": "extensions",
  "removed_release": "1.22",
  "resource": "ingresses",
  "subresource": "",
  "version": "v1beta1"
}
{
  "group": "rbac.authorization.k8s.io",
  "removed_release": "1.22",
  "resource": "clusterroles",
  "subresource": "",
  "version": "v1beta1"
}

kubectl get --raw /metrics | prom2json | jq '
  # set $deprecated to a list of deprecated APIs
  [
    .[] | 
    select(.name=="apiserver_requested_deprecated_apis").metrics[].labels |
    {group,version,resource}
  ] as $deprecated 
  
  |
  
  # select apiserver_request_total metrics which are deprecated
  .[] | select(.name=="apiserver_request_total").metrics[] |
  select(.labels | {group,version,resource} as $key | $deprecated | index($key))
'

{
  "labels": {
    "code": "0",
    "component": "apiserver",
    "contentType": "application/vnd.kubernetes.protobuf;stream=watch",
    "dry_run": "",
    "group": "extensions",
    "resource": "ingresses",
    "scope": "cluster",
    "subresource": "",
    "verb": "WATCH",
    "version": "v1beta1"
  },
  "value": "21"
}
{
  "labels": {
    "code": "200",
    "component": "apiserver",
    "contentType": "application/vnd.kubernetes.protobuf",
    "dry_run": "",
    "group": "extensions",
    "resource": "ingresses",
    "scope": "cluster",
    "subresource": "",
    "verb": "LIST",
    "version": "v1beta1"
  },
  "value": "1"
}
{
  "labels": {
    "code": "200",
    "component": "apiserver",
    "contentType": "application/json",
    "dry_run": "",
    "group": "rbac.authorization.k8s.io",
    "resource": "clusterroles",
    "scope": "cluster",
    "subresource": "",
    "verb": "LIST",
    "version": "v1beta1"
  },
  "value": "1"
}

apiserver_requested_deprecated_apis{removed_release="1.22"} * on(group,version,resource,subresource)
group_right() apiserver_request_total

apiVersion: apiextensions.k8s.io/v1
kind: CustomResourceDefinition
  name: crontabs.example.com
spec:
  versions:
  - name: v1alpha1
    # 这表示 v1alpha1 版本的自定义资源已经废弃了。
    # 对此版本的 API 请求会在服务器响应中收到警告。
    deprecated: true
    # 这会把返回给发出 v1alpha1 API 请求的客户端的默认警告覆盖。
    deprecationWarning: "example.com/v1alpha1 CronTab is deprecated; use example.com/v1 CronTab (see http://example.com/v1alpha1-v1)"
    ...

  - name: v1beta1
    # 这表示 v1beta1 版本的自定义资源已经废弃了。
    # 对此版本的 API 请求会在服务器响应中收到警告。
    # 此版本返回默认警告消息。
    deprecated: true
    ...

  - name: v1
    ...

{
  "apiVersion": "admission.k8s.io/v1",
  "kind": "AdmissionReview",
  "response": {
    "uid": "<value from request.uid>",
    "allowed": true,
    "warnings": [
      ".spec.memory: requests >1GB do not work on Fridays"
    ]
  }
}

import (
  "os"
  "k8s.io/client-go/rest"
  "k8s.io/kubectl/pkg/util/term"
  ...
)

func main() {
  rest.SetDefaultWarningHandler(
    rest.NewWarningWriter(os.Stderr, rest.WarningWriterOptions{
        // only print a given warning the first time we receive it
        Deduplicate: true,
        // highlight the output with color when the output supports it
        Color: term.AllowsColorOutput(os.Stderr),
      },
    ),
  )

  ...

import (
  "k8s.io/client-go/rest"
  "k8s.io/client-go/kubernetes"
)

func getClientWithoutWarnings(config *rest.Config) (kubernetes.Interface, error) {
  // copy to avoid mutating the passed-in config
  config = rest.CopyConfig(config)
  // set the warning handler for this client to ignore warnings
  config.WarningHandler = rest.NoWarnings{}
  // construct and return the client
  return kubernetes.NewForConfig(config)
}