我正在编写一个脚本，该脚本使用k8s.io/client-go库（godocs here）来操纵部署。特别是，我想向标签中的每个Deployment添加一个标签选择器。部署标签选择器为immutable。所以我的方法是：
我不能只使用client-go库按顺序执行步骤1-4，因为我只想在API服务器认为要完成上一步时转到下一步。例如，在API服务器说原始部署已删除之前，我不想执行第3步。否则，我将收到错误消息，即已经存在具有相同名称的部署。
使用客户端库来检测何时完成创建和删除Deployment以及附加回调函数的最佳方法是什么？我遇到了以下软件包。
但是我不确定它们之间有什么区别，以及使用哪一个。
我阅读了watch here和informer here的示例。这里是two related个问题。
watch似乎提供了一种较低级别的方法来监视资源更改并接收有关更改的事件。看来，使用SharedInformerFactory创建一个SharedInformer是可行的方法。
到目前为止我有
const { Provider: CoolProvider, Consumer: CoolConsumer } = React.createContext();
const withCool = Component => props => (
<CoolConsumer>
{cool => <Component {...props} cool={cool} />}
</CoolConsumer>
);
class ChildComponent extends React.Component {
render() {
return this.props.cool ? (
<div>Isn't this cool?</div>
) : (
<div>Not so cool!</div>
);
}
}
const CoolChildComponent = withCool(ChildComponent);
class RootComponent extends React.Component {
render() {
return (
<CoolProvider value={true}>
<ChildComponent ref={(c) => { console.log('Normal child ref', c); }}/>
<CoolChildComponent ref={(c) => { console.log('Cool child ref', c); }}/>
</CoolProvider>
);
}
}
ReactDOM.render(<RootComponent />, document.querySelector('#cool'));
答案 0 :(得分：1)
我最终使用了agg。
这些资源很有帮助。
。
package main
import (
"encoding/json"
"errors"
"flag"
"fmt"
"io/ioutil"
"k8s.io/api/apps/v1"
metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
"k8s.io/apimachinery/pkg/types"
"k8s.io/client-go/informers"
"k8s.io/client-go/kubernetes"
"k8s.io/client-go/tools/cache"
"path/filepath"
"strings"
// We need this import to load the GCP auth plugin which is required to authenticate against GKE clusters.
_ "k8s.io/client-go/plugin/pkg/client/auth/gcp"
"k8s.io/client-go/tools/clientcmd"
"log"
"os"
)
const manifestsDir = "manifests"
// Use an empty string to run on all namespaces
const namespace = ""
const newLabelKey = "new-label-to-add"
const tempLabelKey = "temporary"
const tempSuffix = "-temp"
const componentLabelKey = "component"
func main() {
var kubeconfig *string
if home := homeDir(); home != "" {
kubeconfig = flag.String("kubeconfig", filepath.Join(home, ".kube", "config"), "(optional) absolute path to the kubeconfig file")
} else {
kubeconfig = flag.String("kubeconfig", "", "absolute path to the kubeconfig file")
}
flag.Parse()
// use the current context in kubeconfig
// TODO (dxia) How can I specify a masterUrl or even better a kubectl context?
cfg, err := clientcmd.BuildConfigFromFlags("", *kubeconfig)
exitOnErr(err)
kubeclient, err := kubernetes.NewForConfig(cfg)
exitOnErr(err)
fmt.Printf("Getting deployments with '%s' label.\n", componentLabelKey)
deployments, err := kubeclient.AppsV1().Deployments(namespace).List(metav1.ListOptions{
LabelSelector: componentLabelKey,
})
fmt.Printf("Got %d deployments.\n", len(deployments.Items))
exitOnErr(err)
deployments = processDeployments(deployments)
fmt.Println("Saving deployment manifests to disk as backup.")
err = saveDeployments(deployments)
exitOnErr(err)
tempDeployments := appendToDeploymentName(deployments, tempSuffix)
tempDeployments = createDeploymentsWithNewLabel(tempLabelKey, "true", tempDeployments)
factory := informers.NewSharedInformerFactory(kubeclient, 0)
informer := factory.Apps().V1().Deployments().Informer()
stopper := make(chan struct{})
defer close(stopper)
informer.AddEventHandler(cache.ResourceEventHandlerFuncs{
AddFunc: func(obj interface{}) {
d := obj.(*v1.Deployment)
labels := d.GetLabels()
if _, ok := labels[tempLabelKey]; ok {
labelsStr := joinLabelKeyVals(labels)
fmt.Printf("2: Temporary deployment created in namespace %s, name %s, labels '%s'.\n", d.GetNamespace(), d.GetName(), labelsStr)
deploymentToDelete := strings.Replace(d.GetName(), tempSuffix, "", -1)
deployment := getDeployment(d.GetNamespace(), deploymentToDelete, componentLabelKey, kubeclient)
if deployment != nil {
fmt.Printf("3: Now deleting previous deployment in namespace %s, name %s.\n", d.GetNamespace(), deploymentToDelete)
if err := deleteDeployment(d.GetNamespace(), deploymentToDelete, kubeclient); err != nil {
exitOnErr(err)
}
} else {
fmt.Printf("4: Didn't find deployment in namespace %s, name %s, label %s. Skipping.\n", d.GetNamespace(), deploymentToDelete, componentLabelKey)
}
} else if labelVal, ok := labels[newLabelKey]; ok && labelVal == "production" {
fmt.Printf("Normal deployment with '%s' label created in namespace %s, name %s.\n", newLabelKey, d.GetNamespace(), d.GetName())
deploymentToDelete := d.GetName() + tempSuffix
fmt.Printf("6: Now deleting temporary deployment in namespace %s, name %s.\n", d.GetNamespace(), deploymentToDelete)
if err := deleteDeployment(d.GetNamespace(), deploymentToDelete, kubeclient); err != nil {
exitOnErr(err)
}
}
},
DeleteFunc: func(obj interface{}) {
d := obj.(*v1.Deployment)
labels := d.GetLabels()
if _, ok := labels[newLabelKey]; !ok {
if _, ok := labels[tempLabelKey]; !ok {
fmt.Printf("Deployment without '%s' or '%s' label deleted in namespace %s, name %s.\n", newLabelKey, tempLabelKey, d.GetNamespace(), d.GetName())
fmt.Printf("5: Now creating normal deployment with '%s' label in namespace %s, name %s.\n", newLabelKey, d.GetNamespace(), d.GetName())
deploymentToCreate := createDeploymentWithNewLabel(newLabelKey, "production", *d)
if err := createDeploymentOnApi(deploymentToCreate, kubeclient); err != nil {
exitOnErr(err)
}
}
}
},
})
fmt.Println("1: Creating temporary Deployments.")
err = createDeploymentsOnApi(tempDeployments, kubeclient)
exitOnErr(err)
informer.Run(stopper)
}
func getDeployment(namespace string, name string, labelKey string, client *kubernetes.Clientset) *v1.Deployment {
d, err := client.AppsV1().Deployments(namespace).Get(name, metav1.GetOptions{})
if err != nil {
return nil
}
if _, ok := d.GetLabels()[labelKey]; !ok {
return nil
}
return d
}
func createDeploymentWithNewLabel(key string, val string, deployment v1.Deployment) v1.Deployment {
newDeployment := deployment.DeepCopy()
labels := newDeployment.GetLabels()
if labels == nil {
labels = make(map[string]string)
newDeployment.SetLabels(labels)
}
labels[key] = val
podTemplateSpecLabels := newDeployment.Spec.Template.GetLabels()
if podTemplateSpecLabels == nil {
podTemplateSpecLabels = make(map[string]string)
newDeployment.Spec.Template.SetLabels(podTemplateSpecLabels)
}
podTemplateSpecLabels[key] = val
labelSelectors := newDeployment.Spec.Selector.MatchLabels
if labelSelectors == nil {
labelSelectors = make(map[string]string)
newDeployment.Spec.Selector.MatchLabels = labelSelectors
}
labelSelectors[key] = val
return *newDeployment
}
func createDeploymentsWithNewLabel(key string, val string, deployments *v1.DeploymentList) *v1.DeploymentList {
newDeployments := &v1.DeploymentList{}
for _, d := range deployments.Items {
newDeployment := createDeploymentWithNewLabel(key, val, d)
newDeployments.Items = append(newDeployments.Items, newDeployment)
}
return newDeployments
}
func setAPIVersionAndKindForDeployment(d v1.Deployment, apiVersion string, kind string) {
// These fields are empty strings.
// Looks like an open issue: https://github.com/kubernetes/kubernetes/issues/3030.
d.APIVersion = apiVersion
d.Kind = kind
}
func processDeployments(deployments *v1.DeploymentList) *v1.DeploymentList {
newDeployments := &v1.DeploymentList{}
for _, d := range deployments.Items {
// Set APIVersion and Kind until https://github.com/kubernetes/kubernetes/issues/3030 is fixed
setAPIVersionAndKindForDeployment(d, "apps/v1", "Deployment")
d.Status = v1.DeploymentStatus{}
d.SetUID(types.UID(""))
d.SetSelfLink("")
d.SetGeneration(0)
d.SetCreationTimestamp(metav1.Now())
newDeployments.Items = append(newDeployments.Items, d)
}
return newDeployments
}
func saveDeployments(deployments *v1.DeploymentList) error {
for _, d := range deployments.Items {
if err := saveManifest(d); err != nil {
return err
}
}
return nil
}
func saveManifest(resource interface{}) error {
var path = manifestsDir
var name string
var err error
switch v := resource.(type) {
case v1.Deployment:
path = fmt.Sprintf("%s%s/%s/%s", path, v.GetClusterName(), v.GetNamespace(), "deployments")
name = v.GetName()
default:
return errors.New(fmt.Sprintf("Got an unknown resource kind: %v", resource))
}
bytes, err := json.MarshalIndent(resource, "", " ")
if err != nil {
return err
}
err = os.MkdirAll(path, 0755)
if err != nil {
return err
}
err = ioutil.WriteFile(fmt.Sprintf("%s/%s", path, name), bytes, 0644)
if err != nil {
return err
}
return nil
}
func deleteDeployment(namespace string, name string, client *kubernetes.Clientset) error {
if err := client.AppsV1().Deployments(namespace).Delete(name, &metav1.DeleteOptions{}); err != nil {
return err
}
return nil
}
func appendToDeploymentName(deployments *v1.DeploymentList, suffix string) *v1.DeploymentList {
newDeployments := &v1.DeploymentList{}
for _, d := range deployments.Items {
d.SetName(fmt.Sprintf("%s%s", d.GetName(), suffix))
newDeployments.Items = append(newDeployments.Items, d)
}
return newDeployments
}
func createDeploymentOnApi(d v1.Deployment, client *kubernetes.Clientset) error {
d.SetResourceVersion("")
if _, err := client.AppsV1().Deployments(d.GetNamespace()).Create(&d); err != nil {
return err
}
return nil
}
func createDeploymentsOnApi(deployments *v1.DeploymentList, client *kubernetes.Clientset) error {
for _, d := range deployments.Items {
if err := createDeploymentOnApi(d, client); err != nil {
return err
}
}
return nil
}
func joinLabelKeyVals(labels map[string]string) string {
labelKeyVals := make([]string, 0, len(labels))
for k, v := range labels {
labelKeyVals = append(labelKeyVals, fmt.Sprintf("%v=%v", k, v))
}
return strings.Join(labelKeyVals, ", ")
}
func homeDir() string {
if h := os.Getenv("HOME"); h != "" {
return h
}
return os.Getenv("USERPROFILE") // windows
}
func exitOnErr(err error) {
if err != nil {
log.Fatal(err)
}
}
答案 1 :(得分：0)
也许 MutatingAdmissionWebhook 会是一个很好的解决方案。有了它，您可以根据需要即时改变原始部署。