Invalid value for "-out"; valid values are [go-template, hcl

Error message

Invalid value for "-out"; valid values are [go-template, hcl, json, none, table]

What it means

validateOutputFlag rejects any -out value other than the supported set: go-template, hcl, json, none, table. The error enumerates the valid values (errInvalidOutFormat) so the user can correct the flag.

Source

Thrown at command/var_put.go:612

	default:
		return errors.New(errInvalidInFormat)
	}
}

func (c *VarPutCommand) validateOutputFlag() error {
	if c.outFmt != "go-template" && c.tmpl != "" {
		return errors.New(errUnexpectedTemplate)
	}
	switch c.outFmt {
	case "none", "json", "hcl", "table":
		return nil
	case "go-template":
		if c.tmpl == "" {
			return errors.New(errMissingTemplate)
		}
		return nil
	default:
		return errors.New(errInvalidOutFormat)
	}
}

func warnInvalidIdentifier(in string) error {
	invalid := invalidIdentifier.FindAllString(in, -1)
	if len(invalid) == 0 {
		return nil
	}

	// Use %s instead of %q to avoid escaping characters.
	return fmt.Errorf(
		`"%s" contains characters %s that require the 'index' function for direct access in templates`,
		in,
		formatInvalidVarKeyChars(invalid),
	)
}

func formatInvalidVarKeyChars(invalid []string) string {

View on GitHub (pinned to 482b49bf1a)

Solutions

Use one of the exact valid values: -out go-template, hcl, json, none, or table (lowercase)
Correct the typo/casing in the -out flag value
If templating is needed, use go-template together with -template

Example fix

// before
nomad var put -out yaml app/secret key=value
// after
nomad var put -out json app/secret key=value

Defensive patterns

Strategy: validation

Validate before calling

var valid = map[string]bool{"go-template":true,"hcl":true,"json":true,"none":true,"table":true}
if !valid[out] {
    return fmt.Errorf("invalid -out %q; valid: go-template, hcl, json, none, table", out)
}

Prevention

Use flag completion/whitelists in scripts generating -out values
Remember formats are lowercase and case-sensitive
Pin -out choices in wrapper scripts instead of free-form user input

When it happens

Trigger: Passing any string other than 'none', 'json', 'hcl', 'table', or 'go-template' to the -out flag of commands that call validateOutputFlag (e.g. `var put -out yaml ...`).

Common situations: Typos like `-out templte` or `-out JSON` (case-sensitive switch); carrying over formats from other tools (yaml, pretty); scripting that interpolates an unsupported value into -out.

Understand the failure class

Background: Invalid enum value errors: "Unknown type", "Invalid scope", "must be one of" — when a string is not on the library's allowed list — this error's family across 23 libraries.

Related errors

AI-assisted analysis of hashicorp/nomad@482b49bf1a (2026-09-04). Data as JSON: /api/errors/56bfe8c6b58ec38e. Report an issue: GitHub.