use go 1.12

Signed-off-by: hongming <talonwan@yunify.com>

pkg/simple/client/k8s/k8sclient.go

@@ -0,0 +1,91 @@
+/*
+
+ Copyright 2019 The KubeSphere Authors.
+
+ Licensed under the Apache License, Version 2.0 (the "License");
+ you may not use this file except in compliance with the License.
+ You may obtain a copy of the License at
+
+     http://www.apache.org/licenses/LICENSE-2.0
+
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+
+*/
+
+package k8s
+
+import (
+	"flag"
+	"fmt"
+	"log"
+	"os"
+	"sync"
+
+	"k8s.io/client-go/tools/clientcmd"
+
+	"github.com/mitchellh/go-homedir"
+
+	"k8s.io/client-go/kubernetes"
+	"k8s.io/client-go/rest"
+)
+
+var (
+	kubeConfigFile string
+	k8sClient      *kubernetes.Clientset
+	k8sClientOnce  sync.Once
+	KubeConfig     *rest.Config
+)
+
+func init() {
+	flag.StringVar(&kubeConfigFile, "kubeconfig", fmt.Sprintf("%s/.kube/config", os.Getenv("HOME")), "path to kubeconfig file")
+}
+
+func Client() *kubernetes.Clientset {
+
+	k8sClientOnce.Do(func() {
+
+		config, err := Config()
+
+		if err != nil {
+			log.Fatalln(err)
+		}
+
+		k8sClient = kubernetes.NewForConfigOrDie(config)
+
+		KubeConfig = config
+	})
+
+	return k8sClient
+}
+
+func Config() (kubeConfig *rest.Config, err error) {
+
+	if kubeConfigFile == "" {
+		if env := os.Getenv("KUBECONFIG"); env != "" {
+			kubeConfigFile = env
+		} else {
+			if home, err := homedir.Dir(); err == nil {
+				kubeConfigFile = fmt.Sprintf("%s/.kube/config", home)
+			}
+		}
+	}
+
+	if _, err = os.Stat(kubeConfigFile); err == nil {
+		kubeConfig, err = clientcmd.BuildConfigFromFlags("", kubeConfigFile)
+	} else {
+		kubeConfig, err = rest.InClusterConfig()
+	}
+
+	if err != nil {
+		return nil, err
+	}
+
+	kubeConfig.QPS = 1e6
+	kubeConfig.Burst = 1e6
+
+	return kubeConfig, nil
+}