.

Author: poneding

.gitignore

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+.idea
+.vscode

README.md

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+# programming-kubernetes
+
+本仓库会存储我在学习 Kubernetes 开发过程中的一些笔记和示例代码。
+
+[-> 编程示例](./examples/index.md)
+
+[-> 收藏文章](./collected-articles/index.md)

advanced/gin-informer/main.go

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+package main
+
+import (
+	"fmt"
+	"net/http"
+	"time"
+
+	"pk/basic/client"
+
+	"github.com/gin-gonic/gin"
+	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
+	"k8s.io/apimachinery/pkg/labels"
+	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/apimachinery/pkg/runtime/schema"
+	"k8s.io/apimachinery/pkg/util/wait"
+	"k8s.io/client-go/informers"
+	ctrl "sigs.k8s.io/controller-runtime"
+)
+
+var (
+	sharedInformers informers.SharedInformerFactory
+)
+
+func init() {
+	setupInformers()
+}
+
+func setupInformers() {
+	konfig := ctrl.GetConfigOrDie()
+	fmt.Printf("konfig.Host: %v\n", konfig.Host)
+	fmt.Printf("konfig.ServerName: %v\n", konfig.ServerName)
+	fmt.Printf("konfig.APIPath: %v\n", konfig.APIPath)
+	clientset := client.Clientset(konfig)
+
+	sharedInformers = informers.NewSharedInformerFactory(clientset, time.Minute*5)
+
+	gvrs := []schema.GroupVersionResource{
+		{Group: "apps", Version: "v1", Resource: "deployments"},
+		{Group: "apps", Version: "v1", Resource: "statefulsets"},
+		{Group: "apps", Version: "v1", Resource: "daemonsets"},
+		{Group: "", Version: "v1", Resource: "pods"},
+		{Group: "", Version: "v1", Resource: "services"},
+		{Group: "", Version: "v1", Resource: "namespaces"},
+		{Group: "", Version: "v1", Resource: "configmaps"},
+		{Group: "", Version: "v1", Resource: "secrets"},
+	}
+
+	for _, gvr := range gvrs {
+		_, err := sharedInformers.ForResource(gvr)
+		if err != nil {
+			panic(err)
+		}
+	}
+	sharedInformers.Start(wait.NeverStop)
+	sharedInformers.WaitForCacheSync(wait.NeverStop)
+	fmt.Println("synced done.")
+}
+
+func main() {
+	e := gin.Default()
+	e.GET("/pods", listPods)
+	e.GET("/:g/:v/:r", listResources)
+
+	e.Run(":8888")
+}
+
+func listPods(c *gin.Context) {
+	pods, err := sharedInformers.Core().V1().Pods().Lister().Pods("default").List(labels.Everything())
+	if err != nil {
+		c.JSON(http.StatusInternalServerError, gin.H{
+			"code": http.StatusInternalServerError,
+			"msg":  err.Error(),
+		})
+		return
+	}
+
+	var res []string
+	for _, pod := range pods {
+		res = append(res, pod.Name)
+	}
+	c.JSON(http.StatusOK, gin.H{
+		"code": http.StatusOK,
+		"msg":  fmt.Sprintln(res),
+	})
+}
+
+func listResources(c *gin.Context) {
+	g := c.Param("g")
+	v := c.Param("v")
+	r := c.Param("r")
+
+	gvr := schema.GroupVersionResource{
+		Group:    g,
+		Version:  v,
+		Resource: r,
+	}
+	gi, err := sharedInformers.ForResource(gvr)
+	if err != nil {
+		c.JSON(http.StatusInternalServerError, gin.H{
+			"code": http.StatusInternalServerError,
+			"msg":  err.Error(),
+		})
+	}
+
+	objs, err := gi.Lister().List(labels.Everything())
+	if err != nil {
+		c.JSON(http.StatusInternalServerError, gin.H{
+			"code": http.StatusInternalServerError,
+			"msg":  err.Error(),
+		})
+	}
+
+	var res []interface{}
+	for _, obj := range objs {
+		unstructuredObj, err := runtime.DefaultUnstructuredConverter.ToUnstructured(obj)
+		if err != nil {
+			c.JSON(http.StatusInternalServerError, gin.H{
+				"code": http.StatusInternalServerError,
+				"msg":  err.Error(),
+			})
+			return
+		}
+
+		name, ok, err := unstructured.NestedString(unstructuredObj, "metadata", "name")
+		if err != nil || !ok {
+			c.JSON(http.StatusInternalServerError, gin.H{
+				"code": http.StatusInternalServerError,
+				"msg":  "get name failed",
+			})
+			return
+		}
+		namespace, _, _ := unstructured.NestedString(unstructuredObj, "metadata", "namespace")
+		res = append(res, struct {
+			Group     string `json:"group"`
+			Version   string `json:"version"`
+			Kind      string `json:"kind"`
+			Name      string `json:"name"`
+			Namespace string `json:"namespace,omitempty"`
+		}{
+			Group:     obj.GetObjectKind().GroupVersionKind().Group,
+			Version:   obj.GetObjectKind().GroupVersionKind().Version,
+			Kind:      obj.GetObjectKind().GroupVersionKind().Kind,
+			Name:      name,
+			Namespace: namespace,
+		})
+	}
+	c.JSON(http.StatusOK, gin.H{
+		"code": http.StatusOK,
+		"msg":  res,
+	})
+}

basic/client/ctrl_client.go

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+package client
+
+import (
+	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/client-go/kubernetes/scheme"
+	"k8s.io/client-go/rest"
+	runtimecli "sigs.k8s.io/controller-runtime/pkg/client"
+	// 假设定义了一个 foo CRD，里面包含 register.go 中定义了 AddToScheme 实例
+	// foosv1 "pkg/apis/foos/v1"
+)
+
+func RuntimeClient(config *rest.Config) runtimecli.Client {
+	client, err := runtimecli.New(config, runtimecli.Options{
+		Scheme: scheme.Scheme,
+	})
+	if err != nil {
+		panic(err)
+	}
+	return client
+}
+
+func RuntimeClientForCRD(config *rest.Config) runtimecli.Client {
+	crScheme := runtime.NewScheme()
+	// foosv1.AddToScheme(scheme.Scheme)
+	client, err := runtimecli.New(config, runtimecli.Options{
+		Scheme: crScheme,
+	})
+	if err != nil {
+		panic(err)
+	}
+	return client
+}

basic/client/discovery_client.go

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+package client
+
+import (
+	"k8s.io/client-go/discovery"
+	"k8s.io/client-go/rest"
+)
+
+func DiscoveryClient(config *rest.Config) *discovery.DiscoveryClient {
+	client, err := discovery.NewDiscoveryClientForConfig(config)
+	if err != nil {
+		panic(err)
+	}
+	return client
+}

basic/client/dynamic_client.go

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+package client
+
+import (
+	"k8s.io/client-go/dynamic"
+	"k8s.io/client-go/rest"
+)
+
+func DynamicClient(config *rest.Config) dynamic.Interface {
+	client, err := dynamic.NewForConfig(config)
+	if err != nil {
+		panic(err)
+	}
+	return client
+}

basic/client/http_client.go

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+package client
+
+import (
+	"net/http"
+
+	"k8s.io/client-go/rest"
+)
+
+func HTTPClient(config *rest.Config) *http.Client {
+	client, err := rest.HTTPClientFor(config)
+	if err != nil {
+		panic(err)
+	}
+	return client
+}

basic/client/kubernetes_clientset.go

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+package client
+
+import (
+	"k8s.io/client-go/kubernetes"
+	"k8s.io/client-go/rest"
+)
+
+func Clientset(config *rest.Config) *kubernetes.Clientset {
+	client, err := kubernetes.NewForConfig(config)
+	if err != nil {
+		panic(err)
+	}
+	return client
+}

basic/client/rest_client.go

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+package client
+
+import "k8s.io/client-go/rest"
+
+func RESTClient(config *rest.Config) *rest.RESTClient {
+	client, err := rest.RESTClientFor(config)
+	if err != nil {
+		panic(err)
+	}
+	return client
+}

basic/config/config_test.go

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+package config_test
+
+import (
+	"context"
+	"fmt"
+	"testing"
+
+	"pk/basic/config"
+
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/client-go/kubernetes"
+)
+
+func TestConfig(t *testing.T) {
+	clientset, _ := kubernetes.NewForConfig(config.KubeConfigFromFlags())
+	// clientset2, _ := kubernetes.NewForConfig(config.KubeConfigFromInClusterConfig())
+	// clientset3, _ := kubernetes.NewForConfig(config.KubeConfigFromCtrlRuntime())
+	// clientset4, _ := kubernetes.NewForConfig(config.KubeConfigFromConfigContent())
+	pods, _ := clientset.CoreV1().Pods(metav1.NamespaceDefault).List(context.TODO(), metav1.ListOptions{})
+	if pods != nil {
+		for _, pod := range pods.Items {
+			fmt.Println(pod.Name)
+		}
+	}
+}