// ConfigAndEnvProcessing uses spf13/viper for overriding CLI parameters
func ConfigAndEnvProcessing() error {
	configPath := filepath.Dir(root.IstioConfig)
	baseName := filepath.Base(root.IstioConfig)
	configType := filepath.Ext(root.IstioConfig)
	configName := baseName[0 : len(baseName)-len(configType)]
	if configType != "" {
		configType = configType[1:]
	}

	// Allow users to override some variables through $HOME/.istioctl/config.yaml