ing

config.go

@@ -81,6 +81,7 @@ type Configurator interface {
 	UnmarshalKey(key string, rawVal interface{}) error
 	Unmarshal(rawVal interface{}) error
 	UnmarshalExact(rawVal interface{}) error
+	Marshal(configType string) ([]byte, error)
 	BindPFlags(flags *pflag.FlagSet) error
 	BindPFlag(key string, flag *pflag.Flag) error
 	BindFlagValues(flags FlagValueSet) (err error)
@@ -594,6 +595,13 @@ func (c *configurator) searchMap(source map[string]interface{}, path []string) i
 	return nil
 }
 
+// Marshal marshals the config to []byte.
+func Marshal(configType string) ([]byte, error) { return _c.Marshal(configType) }
+func (c *configurator) Marshal(configType string) ([]byte, error) {
+
+	return marshallConfig(c.config, configType)
+}
+
 // UnmarshalKey takes a single key and unmarshals it into a Struct.
 func UnmarshalKey(key string, rawVal interface{}) error { return _c.UnmarshalKey(key, rawVal) }
 func (c *configurator) UnmarshalKey(key string, rawVal interface{}) error {

util.go

@@ -28,6 +28,16 @@ func (pe ConfigParseError) Error() string {
 	return fmt.Sprintf("While parsing config: %s", pe.err.Error())
 }
 
+// ConfigMarshalError denotes failing to marshal configuration.
+type ConfigMarshalError struct {
+	err error
+}
+
+// Error returns the formatted marshal error.
+func (me ConfigMarshalError) Error() string {
+	return fmt.Sprintf("While marshaling config: %s", me.err.Error())
+}
+
 func absPathify(inPath string) (string, error) {
 	if strings.HasPrefix(inPath, "$HOME") {
 		inPath = userHomeDir() + inPath[5:]
@@ -81,6 +91,33 @@ func exists(path string) (bool, error) {
 	return false, err
 }
 
+func marshallConfig(c map[string]interface{}, configType string) ([]byte, error) {
+	var (
+		buf []byte
+		err error
+	)
+
+	switch strings.ToLower(configType) {
+	case "yaml", "yml":
+		if buf, err = yaml.Marshal(c); err != nil {
+			return nil, ConfigMarshalError{err}
+		}
+
+	case "json":
+		if buf, err = json.Marshal(c); err != nil {
+			return nil, ConfigMarshalError{err}
+		}
+
+	case "toml":
+		if buf, err = toml.Marshal(c); err != nil {
+			return nil, ConfigMarshalError{err}
+		}
+
+	}
+
+	return buf, nil
+}
+
 func unmarshallConfigReader(in io.Reader, c map[string]interface{}, configType string) error {
 	buf := new(bytes.Buffer)
 	buf.ReadFrom(in)