kubernetes/kops · error

error launching editor: %v

Error message

error launching editor: %v

What it means

RunEditInstanceGroup wraps any failure from editor.LaunchTempFile, which creates a temp file and spawns $KOPS_EDITOR/$EDITOR (default vi) to edit the serialized InstanceGroup. If the editor binary is missing, not executable, or the temp file cannot be created/written, the error is wrapped as "error launching editor" and returned, with the original file preserved on disk for recovery.

Source

Thrown at cmd/kops/edit_instancegroup.go:198

	containsError := false

	for {
		buf := &bytes.Buffer{}
		results.header.writeTo(buf)
		results.header.flush()

		if !containsError {
			buf.Write(raw)
		} else {
			buf.Write(stripComments(edited))
		}

		// launch the editor
		editedDiff := edited
		edited, file, err = editor.LaunchTempFile(fmt.Sprintf("%s-edit-", filepath.Base(os.Args[0])), ext, buf)
		if err != nil {
			return preservedFile(fmt.Errorf("error launching editor: %v", err), results.file, out)
		}

		if containsError {
			if bytes.Equal(stripComments(editedDiff), stripComments(edited)) {
				return preservedFile(fmt.Errorf("%s", "Edit cancelled: no valid changes were saved."), file, out)
			}
		}

		if len(results.file) > 0 {
			try.RemoveFile(results.file)
		}

		if bytes.Equal(stripComments(raw), stripComments(edited)) {
			try.RemoveFile(file)
			fmt.Fprintln(out, "Edit cancelled: no changes made.")
			return nil
		}

View on GitHub (pinned to 4c8573c808)

Solutions

1. Set a working editor: export KOPS_EDITOR=vim (or EDITOR=nano) before running the command
2. Verify the editor binary exists in PATH (which $EDITOR) and is executable
3. Check TMPDIR is writable and has free space (df -h /tmp)
4. Skip the editor entirely: write the desired YAML to a file and use `kops replace -f` or `kops edit` with the file-based workflow

Example fix

// before
kops edit instancegroup nodes  # EDITOR=code (GUI, fails headless)
// after
KOPS_EDITOR=vim kops edit instancegroup nodes

editor := os.Getenv("KOPS_EDITOR"); if editor == "" { editor = os.Getenv("EDITOR") }
if editor == "" { editor = "vi" }
if _, err := exec.LookPath(editor); err != nil {
    return fmt.Errorf("editor %q not found in PATH: %w", editor, err)
}

if err := runEdit(); err != nil {
    if strings.Contains(err.Error(), "error launching editor") {
        // fall back to non-interactive workflow: kops get -o yaml > ig.yaml; edit; kops replace -f ig.yaml
    }
}

When it happens

Trigger: Running `kops edit instancegroup <name>` when no EDITOR/KOPS_EDITOR is set or points to a nonexistent binary; the temp directory is unwritable/full; the resolved ext/format has no registered temp-file writer.

Common situations: Running kops in a minimal Docker container or CI job with no editor installed; EDITOR set to a GUI app that fails to launch headless; read-only TMPDIR or full disk.

Related errors

• error launching editor: %v
• Edit cancelled: no valid changes were saved.
• error creating temp dir: %v
• Error too many '=' (%d) in %s
• at least one channel URL is required

AI-assisted analysis of kubernetes/kops@4c8573c808 (2026-09-05). Data as JSON: /api/errors/c08709bf06462fd7. Report an issue: GitHub.