简介

gvk用于yaml中.对应资源对象(比如pod)

gvr用于url中,对应资源crud等的api

比如我们kubectl create -f xx.yaml时

读取yaml,得到gvk
discovery client访问apiserver得到restmapper
通过restmapper难道gvk对应的gvr
根据gvr拼接url
对指定url发送对应的yaml内容

可以通过kubectl get --raw='/api'或者kubectl get --raw='/apis'查看有哪些gv

如可以通过kubectl get --raw='/api/v1' 查看有哪些gvr以及gvr对应的kind

示例

package main

import (
    "context"
    "io/ioutil"

    "k8s.io/client-go/rest"

    "k8s.io/apimachinery/pkg/api/meta"
    metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
    "k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
    yamlCodec "k8s.io/apimachinery/pkg/runtime/serializer/yaml"
    "k8s.io/client-go/discovery"
    memory "k8s.io/client-go/discovery/cached"
    "k8s.io/client-go/dynamic"
    "k8s.io/client-go/restmapper"
)

func main() {
    data, err := ioutil.ReadFile("./demo.yaml")
    if err != nil {
        panic(err)
    }
    restConfig := &rest.Config{
        Host:        "yourk8shost",
        BearerToken: "yourtoken",
        TLSClientConfig: rest.TLSClientConfig{
            Insecure: true,
        },
    }
    ctx := context.TODO()
    codec := yamlCodec.NewDecodingSerializer(unstructured.UnstructuredJSONScheme)

    discoveryClient, err := discovery.NewDiscoveryClientForConfig(restConfig)
    if err != nil {
        panic(err)
    }

    mapper := restmapper.NewDeferredDiscoveryRESTMapper(memory.NewMemCacheClient(discoveryClient))
    dynamicClient, err := dynamic.NewForConfig(restConfig)
    if err != nil {
        panic(err)
    }

    obj := &unstructured.Unstructured{}
    _, gvk, err := codec.Decode(data, nil, obj)
    if err != nil {
        panic(err)
    }

    mapping, err := mapper.RESTMapping(gvk.GroupKind(), gvk.Version)
    if err != nil {
        panic(err)
    }

    var dynamicResource dynamic.ResourceInterface = dynamicClient.Resource(mapping.Resource)
    if mapping.Scope.Name() == meta.RESTScopeNameNamespace {
        namesapce := obj.GetNamespace()
        if namesapce == "" {
            namesapce = "default"
        }
        dynamicResource = dynamicClient.Resource(mapping.Resource).Namespace(namesapce)
    }

    if _, err := dynamicResource.Create(ctx, obj, metav1.CreateOptions{}); err != nil {
        panic(err)
    }
}