feat: kubeconfig path flag (#329)

* feat: kubeconfig path flag

* fix: GetConfig comment

---------

Co-authored-by: Andy Suderman <andy@fairwinds.com>

cmd/root.go

@@ -97,6 +97,12 @@ func init() {
 		klog.Exitf("Failed to bind context flag: %v", err)
 	}
 
+	rootCmd.PersistentFlags().String("kubeconfig", "", "A path to a kubeconfig file.")
+	err = viper.BindPFlag("kubeconfig", rootCmd.PersistentFlags().Lookup("kubeconfig"))
+	if err != nil {
+		klog.Exitf("Failed to bind kubeconfig flag: %v", err)
+	}
+
 	rootCmd.PersistentFlags().Bool("wide", false, "Output chart name and namespace")
 	err = viper.BindPFlag("wide", rootCmd.PersistentFlags().Lookup("wide"))
 	if err != nil {
@@ -252,14 +258,15 @@ var findCmd = &cobra.Command{
 		klog.V(5).Infof("All Keys: %v", viper.AllKeys())
 
 		kubeContext := viper.GetString("context")
+		kubeConfigPath := viper.GetString("kubeconfig")
 
 		format := viper.GetString("format")
 		if !(format == output.TableFormat || format == output.JSONFormat) {
 			klog.Exitf("--format flag value is not valid. Run `nova find --help` to see flag options")
 		}
 
 		if viper.GetBool("helm") && viper.GetBool("containers") {
-			output, err := handleHelmAndContainers(kubeContext)
+			output, err := handleHelmAndContainers(kubeContext, kubeConfigPath)
 			if err != nil {
 				klog.Exit(err)
 			}
@@ -276,15 +283,15 @@ var findCmd = &cobra.Command{
 		}
 
 		if viper.GetBool("containers") {
-			output, err := handleContainers(kubeContext)
+			output, err := handleContainers(kubeContext, kubeConfigPath)
 			if err != nil {
 				klog.Exit(err)
 			}
 			output.Print(format)
 			return
 		}
 
-		output, err := handleHelm(kubeContext)
+		output, err := handleHelm(kubeContext, kubeConfigPath)
 		if err != nil {
 			klog.Exit(err)
 		}
@@ -321,7 +328,7 @@ func Execute(VERSION, COMMIT string) {
 	}
 }
 
-func handleContainers(kubeContext string) (*output.ContainersOutput, error) {
+func handleContainers(kubeContext, kubeConfigPath string) (*output.ContainersOutput, error) {
 	// Set up a context we can use to cancel all operations to external container registries if we need to
 	timeout := time.Duration(viper.GetUint16("timeout")) * time.Second
 	ctx, cancel := context.WithTimeout(context.Background(), timeout)
@@ -339,7 +346,7 @@ func handleContainers(kubeContext string) (*output.ContainersOutput, error) {
 		case <-ctx.Done():
 		}
 	}()
-	iClient := containers.NewClient(kubeContext)
+	iClient := containers.NewClient(kubeContext, kubeConfigPath)
 	namespace := viper.GetString("namespace")
 	if viper.IsSet("namespace") {
 		klog.V(3).Infof("Scanning namespace %v", namespace)
@@ -356,8 +363,8 @@ func handleContainers(kubeContext string) (*output.ContainersOutput, error) {
 	return output.NewContainersOutput(containers.Images, containers.ErrImages, showNonSemver, showErrored, includeAll), nil
 }
 
-func handleHelm(kubeContext string) (*output.Output, error) {
-	h := nova_helm.NewHelm(kubeContext)
+func handleHelm(kubeContext, kubeConfigPath string) (*output.Output, error) {
+	h := nova_helm.NewHelm(kubeContext, kubeConfigPath)
 	if viper.IsSet("desired-versions") {
 		klog.V(3).Infof("desired-versions is set - attempting to load them")
 		klog.V(8).Infof("raw desired-versions: %v", viper.Get("desired-versions"))
@@ -412,12 +419,12 @@ func handleHelm(kubeContext string) (*output.Output, error) {
 	return &out, nil
 }
 
-func handleHelmAndContainers(kubeContext string) (*output.HelmAndContainersOutput, error) {
-	helmOutput, err := handleHelm(kubeContext)
+func handleHelmAndContainers(kubeContext, kubeConfigPath string) (*output.HelmAndContainersOutput, error) {
+	helmOutput, err := handleHelm(kubeContext, kubeConfigPath)
 	if err != nil {
 		return nil, err
 	}
-	containersOutput, err := handleContainers(kubeContext)
+	containersOutput, err := handleContainers(kubeContext, kubeConfigPath)
 	if err != nil {
 		return nil, err
 	}

pkg/containers/images.go

@@ -93,9 +93,9 @@ type Tag struct {
 }
 
 // NewClient is a constructor to create a new Client
-func NewClient(kubeContext string) *Client {
+func NewClient(kubeContext, kubeConfigPath string) *Client {
 	return &Client{
-		Kube: kube.GetConfigInstance(kubeContext),
+		Kube: kube.GetConfigInstance(kubeContext, kubeConfigPath),
 	}
 }
 

pkg/helm/cluster.go

@@ -39,9 +39,9 @@ type DesiredVersion struct {
 }
 
 // NewHelm returns a basic helm struct with the version of helm requested
-func NewHelm(kubeContext string) *Helm {
+func NewHelm(kubeContext, kubeConfigPath string) *Helm {
 	return &Helm{
-		Kube: kube.GetConfigInstance(kubeContext),
+		Kube: kube.GetConfigInstance(kubeContext, kubeConfigPath),
 	}
 }
 

pkg/kube/kube.go

@@ -15,6 +15,7 @@
 package kube
 
 import (
+	"flag"
 	"sync"
 
 	"k8s.io/apimachinery/pkg/api/meta"
@@ -45,19 +46,38 @@ var (
 )
 
 // GetConfigInstance returns a Kubernetes interface based on the current configuration
-func GetConfigInstance(context string) *Connection {
+func GetConfigInstance(context, kubeConfigPath string) *Connection {
 	once.Do(func() {
 		kubeClient = &Connection{
-			Client:        getKubeClient(context),
-			DynamicClient: getDynamicKubeClient(context),
-			RESTMapper:    getRESTMapper(context),
+			Client:        getKubeClient(context, kubeConfigPath),
+			DynamicClient: getDynamicKubeClient(context, kubeConfigPath),
+			RESTMapper:    getRESTMapper(context, kubeConfigPath),
 		}
 	})
 	return kubeClient
 }
 
-func getKubeClient(context string) kubernetes.Interface {
-	kubeConf, err := config.GetConfigWithContext(context)
+// GetConfig returns a *rest.Config based on the current configuration
+func GetConfig(context, kubeConfigPath string) (*rest.Config, error) {
+
+	if context != "" {
+		klog.V(3).Infof("using kube context: %s", context)
+	}
+
+	fs := flag.NewFlagSet("fs", flag.ContinueOnError)
+	fs.String("kubeconfig", kubeConfigPath, "")
+	config.RegisterFlags(fs)
+
+	kubeConfig, err := config.GetConfigWithContext(context)
+	if err != nil {
+		return nil, err
+	}
+
+	return kubeConfig, nil
+}
+
+func getKubeClient(context, kubeConfigPath string) kubernetes.Interface {
+	kubeConf, err := GetConfig(context, kubeConfigPath)
 	if err != nil {
 		klog.Fatalf("error getting config with context %s: %v", context, err)
 	}
@@ -69,8 +89,8 @@ func getKubeClient(context string) kubernetes.Interface {
 	return clientset
 }
 
-func getDynamicKubeClient(context string) dynamic.Interface {
-	kubeConf, err := config.GetConfigWithContext(context)
+func getDynamicKubeClient(context, kubeConfigPath string) dynamic.Interface {
+	kubeConf, err := GetConfig(context, kubeConfigPath)
 	if err != nil {
 		klog.Fatalf("error getting config with context %s: %v", context, err)
 	}
@@ -81,8 +101,8 @@ func getDynamicKubeClient(context string) dynamic.Interface {
 	return dynamicClient
 }
 
-func getRESTMapper(context string) meta.RESTMapper {
-	kubeConf, err := config.GetConfigWithContext(context)
+func getRESTMapper(context, kubeConfigPath string) meta.RESTMapper {
+	kubeConf, err := GetConfig(context, kubeConfigPath)
 	if err != nil {
 		klog.Fatalf("error getting config with context %s: %v", context, err)
 	}