From 5bb84013cdbde36c6010200fc292100a2ae9dca3 Mon Sep 17 00:00:00 2001
From: Katrina Verey <katrina.verey@shopify.com>
Date: Wed, 23 Mar 2022 19:17:29 -0400
Subject: [PATCH] kubectl version should include bundled kustomize version

Kubernetes-commit: 44e63e8ff8e7f98c75dc86d8c41553a5cce6a603
---
 pkg/cmd/version/version.go | 52 +++++++++++++++++++++++++-------------
 1 file changed, 35 insertions(+), 17 deletions(-)

diff --git a/pkg/cmd/version/version.go b/pkg/cmd/version/version.go
index 5d6a7f7b..413f01f1 100644
--- a/pkg/cmd/version/version.go
+++ b/pkg/cmd/version/version.go
@@ -20,6 +20,7 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
+	"runtime/debug"
 
 	"github.com/spf13/cobra"
 	"sigs.k8s.io/yaml"
@@ -34,10 +35,14 @@ import (
 	"k8s.io/kubectl/pkg/util/templates"
 )
 
+// TODO(knverey): remove this hardcoding once kubectl being built with module support makes BuildInfo available.
+const kustomizeVersion = "v4.4.1"
+
 // Version is a struct for version information
 type Version struct {
-	ClientVersion *apimachineryversion.Info `json:"clientVersion,omitempty" yaml:"clientVersion,omitempty"`
-	ServerVersion *apimachineryversion.Info `json:"serverVersion,omitempty" yaml:"serverVersion,omitempty"`
+	ClientVersion    *apimachineryversion.Info `json:"clientVersion,omitempty" yaml:"clientVersion,omitempty"`
+	KustomizeVersion string                    `json:"kustomizeVersion,omitempty" yaml:"kustomizeVersion,omitempty"`
+	ServerVersion    *apimachineryversion.Info `json:"serverVersion,omitempty" yaml:"serverVersion,omitempty"`
 }
 
 var (
@@ -116,32 +121,32 @@ func (o *Options) Validate(args []string) error {
 // Run executes version command
 func (o *Options) Run() error {
 	var (
-		serverVersion *apimachineryversion.Info
-		serverErr     error
-		versionInfo   Version
+		serverErr   error
+		versionInfo Version
 	)
 
-	clientVersion := version.Get()
-	versionInfo.ClientVersion = &clientVersion
+	versionInfo.ClientVersion = func() *apimachineryversion.Info { v := version.Get(); return &v }()
+	versionInfo.KustomizeVersion = getKustomizeVersion()
 
 	if !o.ClientOnly && o.discoveryClient != nil {
 		// Always request fresh data from the server
 		o.discoveryClient.Invalidate()
-		serverVersion, serverErr = o.discoveryClient.ServerVersion()
-		versionInfo.ServerVersion = serverVersion
+		versionInfo.ServerVersion, serverErr = o.discoveryClient.ServerVersion()
 	}
 
 	switch o.Output {
 	case "":
 		if o.Short {
-			fmt.Fprintf(o.Out, "Client Version: %s\n", clientVersion.GitVersion)
-			if serverVersion != nil {
-				fmt.Fprintf(o.Out, "Server Version: %s\n", serverVersion.GitVersion)
+			fmt.Fprintf(o.Out, "Client Version: %s\n", versionInfo.ClientVersion.GitVersion)
+			fmt.Fprintf(o.Out, "Kustomize Version: %s\n", versionInfo.KustomizeVersion)
+			if versionInfo.ServerVersion != nil {
+				fmt.Fprintf(o.Out, "Server Version: %s\n", versionInfo.ServerVersion.GitVersion)
 			}
 		} else {
-			fmt.Fprintf(o.Out, "Client Version: %#v\n", clientVersion)
-			if serverVersion != nil {
-				fmt.Fprintf(o.Out, "Server Version: %#v\n", *serverVersion)
+			fmt.Fprintf(o.Out, "Client Version: %#v\n", *versionInfo.ClientVersion)
+			fmt.Fprintf(o.Out, "Kustomize Version: %s\n", versionInfo.KustomizeVersion)
+			if versionInfo.ServerVersion != nil {
+				fmt.Fprintf(o.Out, "Server Version: %#v\n", *versionInfo.ServerVersion)
 			}
 		}
 	case "yaml":
@@ -162,11 +167,24 @@ func (o *Options) Run() error {
 		return fmt.Errorf("VersionOptions were not validated: --output=%q should have been rejected", o.Output)
 	}
 
-	if serverVersion != nil {
-		if err := printVersionSkewWarning(o.ErrOut, clientVersion, *serverVersion); err != nil {
+	if versionInfo.ServerVersion != nil {
+		if err := printVersionSkewWarning(o.ErrOut, *versionInfo.ClientVersion, *versionInfo.ServerVersion); err != nil {
 			return err
 		}
 	}
 
 	return serverErr
 }
+
+func getKustomizeVersion() string {
+	info, ok := debug.ReadBuildInfo()
+	if !ok {
+		return kustomizeVersion
+	}
+	for _, dep := range info.Deps {
+		if dep.Path == "sigs.k8s.io/kustomize/kustomize/v4" {
+			return dep.Version
+		}
+	}
+	return kustomizeVersion
+}