Merge aa295b144a into 7538d73b4e

util.go

@@ -21,12 +21,14 @@ import (
 	"strings"
 	"unicode"
 
+	yaml "gopkg.in/yaml.v2"
+
 	"github.com/hashicorp/hcl"
 	"github.com/magiconair/properties"
 	toml "github.com/pelletier/go-toml"
+	"github.com/spf13/afero"
 	"github.com/spf13/cast"
 	jww "github.com/spf13/jwalterweatherman"
-	"gopkg.in/yaml.v2"
 )
 
 // ConfigParseError denotes failing to parse configuration file.
@@ -39,6 +41,16 @@ func (pe ConfigParseError) Error() string {
 	return fmt.Sprintf("While parsing config: %s", pe.err.Error())
 }
 
+// ConfigMarshalError happens when failing to marshal the configuration.
+type ConfigMarshalError struct {
+	err error
+}
+
+// Error returns the formatted configuration error.
+func (e ConfigMarshalError) Error() string {
+	return fmt.Sprintf("While marshaling config: %s", e.err.Error())
+}
+
 // toCaseInsensitiveValue checks if the value is a  map;
 // if so, create a copy and lower-case the keys recursively.
 func toCaseInsensitiveValue(value interface{}) interface{} {
@@ -152,6 +164,45 @@ func userHomeDir() string {
 	return os.Getenv("HOME")
 }
 
+func marshalConfigWriter(f afero.File, c map[string]interface{}, configType string) error {
+	switch configType {
+	case "json":
+		b, err := json.MarshalIndent(v.AllSettings(), "", "    ")
+		if err != nil {
+			return ConfigMarshalError{err}
+		}
+		_, err = f.WriteString(string(b))
+		if err != nil {
+			return ConfigMarshalError{err}
+		}
+
+	case "hcl":
+		// TODO: How to convert map to hcl???
+
+	case "prop", "props", "properties":
+
+	case "toml":
+		t := toml.TreeFromMap(v.AllSettings())
+		s := t.String()
+		_, err := f.WriteString(s)
+		if err != nil {
+			return ConfigMarshalError{err}
+		}
+
+	case "yaml", "yml":
+		b, err := yaml.Marshal(v.AllSettings())
+		if err != nil {
+			return ConfigMarshalError{err}
+		}
+		_, err = f.WriteString(string(b))
+		if err != nil {
+			return ConfigMarshalError{err}
+		}
+	}
+
+	return nil
+}
+
 func unmarshallConfigReader(in io.Reader, c map[string]interface{}, configType string) error {
 	buf := new(bytes.Buffer)
 	buf.ReadFrom(in)

viper.go

@@ -30,12 +30,12 @@ import (
 	"strings"
 	"time"
 
-	"github.com/fsnotify/fsnotify"
 	"github.com/mitchellh/mapstructure"
 	"github.com/spf13/afero"
 	"github.com/spf13/cast"
 	jww "github.com/spf13/jwalterweatherman"
 	"github.com/spf13/pflag"
+	"gopkg.in/fsnotify.v1"
 )
 
 var v *Viper
@@ -1147,6 +1147,73 @@ func (v *Viper) MergeConfig(in io.Reader) error {
 	return nil
 }
 
+func writeConfig(filename string, force bool) error { return v.writeConfig(filename, force) }
+func (v *Viper) writeConfig(filename string, force bool) error {
+	jww.INFO.Println("Attempting to write configuration to file.")
+	ext := filepath.Ext(filename)
+	if len(ext) <= 1 {
+		return fmt.Errorf("Filename: %s requires valid extension.", filename)
+	}
+	configType := ext[1:]
+	if !stringInSlice(configType, SupportedExts) {
+		return UnsupportedConfigError(configType)
+	}
+	if v.config == nil {
+		v.config = make(map[string]interface{})
+	}
+	var flags int
+	if force == true {
+		flags = os.O_CREATE | os.O_WRONLY
+	} else {
+		if _, err := os.Stat(filename); os.IsNotExist(err) {
+			flags = os.O_WRONLY
+		} else {
+			return fmt.Errorf("File: %s exists. Use WriteConfig to overwrite.", filename)
+		}
+	}
+	f, err := v.fs.OpenFile(filename, flags, os.FileMode(0644))
+	if err != nil {
+		return err
+	}
+	return v.marshalWriter(f, v.config, configType)
+}
+
+// WriteConfig writes the current configuration to a file.
+func WriteConfig() error { return v.WriteConfig() }
+func (v *Viper) WriteConfig() error {
+	filename, err := v.getConfigFile()
+	if err != nil {
+		return err
+	}
+	return v.writeConfig(filename, true)
+}
+
+// SafeWriteConfig writes current configuration to file only if the file does not exist.
+func SafeWriteConfig() error { return v.SafeWriteConfig() }
+func (v *Viper) SafeWriteConfig() error {
+	filename, err := v.getConfigFile()
+	if err != nil {
+		return err
+	}
+	return v.writeConfig(filename, false)
+}
+
+// WriteConfigAs writes current configuration to a given filename.
+func WriteConfigAs(filename string) error { return v.WriteConfigAs(filename) }
+func (v *Viper) WriteConfigAs(filename string) error {
+	return v.writeConfig(filename, true)
+}
+
+// SafeWriteConfigAs writes current configuration to a given filename is it does not exist.
+func SafeWriteConfigAs(filename string) error { return v.SafeWriteConfigAs(filename) }
+func (v *Viper) SafeWriteConfigAs(filename string) error {
+	return v.writeConfig(filename, false)
+}
+
+// WriteConfigKey writes given key and value to file.
+
+// WriteConfigKeyAs writes given key and value to a given filename.
+
 func keyExists(k string, m map[string]interface{}) string {
 	lk := strings.ToLower(k)
 	for mk := range m {
@@ -1265,6 +1332,15 @@ func (v *Viper) unmarshalReader(in io.Reader, c map[string]interface{}) error {
 	return unmarshallConfigReader(in, c, v.getConfigType())
 }
 
+// Marshal a map into Writer.
+func marshalWriter(out afero.File, c map[string]interface{}, configType string) error {
+	return v.marshalWriter(out, c, configType)
+}
+
+func (v *Viper) marshalWriter(out afero.File, c map[string]interface{}, configType string) error {
+	return marshalConfigWriter(out, c, configType)
+}
+
 func (v *Viper) insensitiviseMaps() {
 	insensitiviseMap(v.config)
 	insensitiviseMap(v.defaults)