Initial commit

vendor/sigs.k8s.io/controller-runtime/pkg/client/config/config.go

@@ -0,0 +1,94 @@
+/*
+Copyright 2017 The Kubernetes 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 config
+
+import (
+	"flag"
+	"fmt"
+	"os"
+	"os/user"
+	"path/filepath"
+
+	"k8s.io/client-go/rest"
+	"k8s.io/client-go/tools/clientcmd"
+	logf "sigs.k8s.io/controller-runtime/pkg/runtime/log"
+)
+
+var (
+	kubeconfig, masterURL string
+	log                   = logf.KBLog.WithName("client").WithName("config")
+)
+
+func init() {
+	// TODO: Fix this to allow double vendoring this library but still register flags on behalf of users
+	flag.StringVar(&kubeconfig, "kubeconfig", "",
+		"Paths to a kubeconfig. Only required if out-of-cluster.")
+
+	flag.StringVar(&masterURL, "master", "",
+		"The address of the Kubernetes API server. Overrides any value in kubeconfig. "+
+			"Only required if out-of-cluster.")
+}
+
+// GetConfig creates a *rest.Config for talking to a Kubernetes apiserver.
+// If --kubeconfig is set, will use the kubeconfig file at that location.  Otherwise will assume running
+// in cluster and use the cluster provided kubeconfig.
+//
+// Config precedence
+//
+// * --kubeconfig flag pointing at a file
+//
+// * KUBECONFIG environment variable pointing at a file
+//
+// * In-cluster config if running in cluster
+//
+// * $HOME/.kube/config if exists
+func GetConfig() (*rest.Config, error) {
+	// If a flag is specified with the config location, use that
+	if len(kubeconfig) > 0 {
+		return clientcmd.BuildConfigFromFlags(masterURL, kubeconfig)
+	}
+	// If an env variable is specified with the config locaiton, use that
+	if len(os.Getenv("KUBECONFIG")) > 0 {
+		return clientcmd.BuildConfigFromFlags(masterURL, os.Getenv("KUBECONFIG"))
+	}
+	// If no explicit location, try the in-cluster config
+	if c, err := rest.InClusterConfig(); err == nil {
+		return c, nil
+	}
+	// If no in-cluster config, try the default location in the user's home directory
+	if usr, err := user.Current(); err == nil {
+		if c, err := clientcmd.BuildConfigFromFlags(
+			"", filepath.Join(usr.HomeDir, ".kube", "config")); err == nil {
+			return c, nil
+		}
+	}
+
+	return nil, fmt.Errorf("could not locate a kubeconfig")
+}
+
+// GetConfigOrDie creates a *rest.Config for talking to a Kubernetes apiserver.
+// If --kubeconfig is set, will use the kubeconfig file at that location.  Otherwise will assume running
+// in cluster and use the cluster provided kubeconfig.
+//
+// Will log an error and exit if there is an error creating the rest.Config.
+func GetConfigOrDie() *rest.Config {
+	config, err := GetConfig()
+	if err != nil {
+		log.Error(err, "unable to get kubeconfig")
+	}
+	return config
+}