feat: install kubectx and kubens

plugins/common/io.go

@@ -154,8 +154,8 @@ func ReadFirstLine(filename string) (text string) {
 // SetPermissionsInput is the input struct for SetPermissions
 type SetPermissionInput struct {
 	Filename  string
-	Mode      os.FileMode
 	GroupName string
+	Mode      os.FileMode
 	Username  string
 }
 
@@ -214,9 +214,11 @@ func TouchFile(filename string) error {
 }
 
 type WriteSliceToFileInput struct {
-	Filename string
-	Lines    []string
-	Mode     os.FileMode
+	Filename  string
+	GroupName string
+	Lines     []string
+	Mode      os.FileMode
+	Username  string
 }
 
 // WriteSliceToFile writes a slice of strings to a file
@@ -239,8 +241,17 @@ func WriteSliceToFile(input WriteSliceToFileInput) error {
 		return err
 	}
 
-	return SetPermissions(SetPermissionInput{
+	permissionsInput := SetPermissionInput{
 		Filename: input.Filename,
 		Mode:     input.Mode,
-	})
+	}
+
+	if input.GroupName != "" {
+		permissionsInput.GroupName = input.GroupName
+	}
+	if input.Username != "" {
+		permissionsInput.Username = input.Username
+	}
+
+	return SetPermissions(permissionsInput)
 }

plugins/scheduler-k3s/functions.go

@@ -14,6 +14,8 @@ import (
 
 	appjson "github.com/dokku/dokku/plugins/app-json"
 	"github.com/dokku/dokku/plugins/common"
+	resty "github.com/go-resty/resty/v2"
+	"golang.org/x/sync/errgroup"
 	"gopkg.in/yaml.v3"
 	corev1 "k8s.io/api/core/v1"
 	v1 "k8s.io/api/core/v1"
@@ -722,6 +724,61 @@ func installHelmCharts(ctx context.Context, clientset KubernetesClient) error {
 	return nil
 }
 
+func installHelperCommands(ctx context.Context) error {
+	urls := map[string]string{
+		"kubectx": "https://github.com/ahmetb/kubectx/releases/latest/download/kubectx",
+		"kubens":  "https://github.com/ahmetb/kubectx/releases/latest/download/kubens",
+	}
+
+	client := resty.New()
+	for binaryName, url := range urls {
+		resp, err := client.R().
+			SetContext(ctx).
+			Get(url)
+		if err != nil {
+			return fmt.Errorf("Unable to download %s: %w", binaryName, err)
+		}
+		if resp == nil {
+			return fmt.Errorf("Missing response from %s download: %w", binaryName, err)
+		}
+
+		if resp.StatusCode() != 200 {
+			return fmt.Errorf("Invalid status code for %s: %d", binaryName, resp.StatusCode())
+		}
+
+		f, err := os.Create(filepath.Join("/usr/local/bin", binaryName))
+		if err != nil {
+			return fmt.Errorf("Unable to create %s: %w", binaryName, err)
+		}
+
+		if err := f.Close(); err != nil {
+			return fmt.Errorf("Unable to close %s file: %w", binaryName, err)
+		}
+
+		err = common.WriteSliceToFile(common.WriteSliceToFileInput{
+			Filename:  f.Name(),
+			GroupName: "root",
+			Lines:     strings.Split(resp.String(), "\n"),
+			Mode:      os.FileMode(0755),
+			Username:  "root",
+		})
+		if err != nil {
+			return fmt.Errorf("Unable to write %s to file: %w", binaryName, err)
+		}
+
+		fi, err := os.Stat(f.Name())
+		if err != nil {
+			return fmt.Errorf("Unable to get %s file size: %w", binaryName, err)
+		}
+
+		if fi.Size() == 0 {
+			return fmt.Errorf("Invalid %s filesize", binaryName)
+		}
+	}
+
+	return nil
+}
+
 func isK3sInstalled() error {
 	if !common.FileExists("/usr/local/bin/k3s") {
 		return fmt.Errorf("k3s binary is not available")
@@ -797,6 +854,17 @@ func kubernetesNodeToNode(node v1.Node) Node {
 	}
 }
 
+func uninstallHelperCommands(ctx context.Context) error {
+	errs, _ := errgroup.WithContext(ctx)
+	errs.Go(func() error {
+		return os.RemoveAll("/usr/local/bin/kubectx")
+	})
+	errs.Go(func() error {
+		return os.RemoveAll("/usr/local/bin/kubens")
+	})
+	return errs.Wait()
+}
+
 func waitForPodBySelectorRunning(ctx context.Context, input WaitForPodBySelectorRunningInput) error {
 	pods, err := waitForPodToExist(ctx, WaitForPodToExistInput{
 		Clientset:     input.Clientset,

plugins/scheduler-k3s/subcommands.go

@@ -84,6 +84,7 @@ func CommandInitialize(serverIP string, taintScheduling bool) error {
 	common.LogInfo2Quiet("Downloading k3s installer")
 	client := resty.New()
 	resp, err := client.R().
+		SetContext(ctx).
 		Get("https://get.k3s.io")
 	if err != nil {
 		return fmt.Errorf("Unable to download k3s installer: %w", err)
@@ -247,6 +248,12 @@ func CommandInitialize(serverIP string, taintScheduling bool) error {
 		return fmt.Errorf("Unable to install helm charts: %w", err)
 	}
 
+	common.LogInfo2Quiet("Installing helper commands")
+	err = installHelperCommands(ctx)
+	if err != nil {
+		return fmt.Errorf("Unable to install helper commands: %w", err)
+	}
+
 	common.LogVerboseQuiet("Done")
 
 	return nil
@@ -709,5 +716,6 @@ func CommandUninstall() error {
 		return fmt.Errorf("Invalid exit code from k3s uninstaller command: %d", uninstallerCmd.ExitCode)
 	}
 
-	return nil
+	common.LogInfo2Quiet("Removing k3s dependencies")
+	return uninstallHelperCommands(context.Background())
 }