fmt.Fprintf(w, "%s\t%s\t%v\n", flag, viper.GetString(flag), configSource(flag, v))
	}
	return w.Flush()
}

func configSource(flag string, v env.VariableInfo) string {
	// Environment variables have high precedence in Viper
	if v.IsSet() {
		return "$" + v.GetName()
	}

	if viper.InConfig(flag) {
		return root.IstioConfig
	}

	return "default"

	ValueSourceCfg
	ValueSourceEnv
)

// ResolveConfigParam returns the effective value of a configuration parameter,
// within a subsystem and subsystem target. The effective value is, in order of
// decreasing precedence:
//
// 1. the value of the corresponding environment variable if set,
// 2. the value of the parameter in the config store if set,
// 3. the default value,
//