move utility method

repo/config/config.go

@@ -2,9 +2,11 @@
 package config
 
 import (
+	"bytes"
 	"encoding/base64"
 	"encoding/json"
 	"errors"
+	"fmt"
 	"os"
 	"path/filepath"
 	"strings"
@@ -205,3 +207,15 @@ func Marshal(value interface{}) ([]byte, error) {
 	// need to prettyprint, hence MarshalIndent, instead of Encoder
 	return json.MarshalIndent(value, "", "  ")
 }
+
+func FromMap(v map[string]interface{}) (*Config, error) {
+	var buf bytes.Buffer
+	if err := json.NewEncoder(&buf).Encode(v); err != nil {
+		return nil, err
+	}
+	var conf Config
+	if err := json.NewDecoder(&buf).Decode(&conf); err != nil {
+		return nil, fmt.Errorf("Failure to decode config: %s", err)
+	}
+	return &conf, nil
+}

repo/fsrepo/fsrepo.go

@@ -149,7 +149,7 @@ func (r *FSRepo) SetConfigKey(key string, value interface{}) error {
 	if err := writeConfigFile(filename, mapconf); err != nil {
 		return err
 	}
-	conf, err := convertMapToConfig(mapconf)
+	conf, err := config.FromMap(mapconf)
 	if err != nil {
 		return err
 	}

repo/fsrepo/serialize.go

@@ -1,7 +1,6 @@
 package fsrepo
 
 import (
-	"bytes"
 	"encoding/json"
 	"fmt"
 	"io"
@@ -73,18 +72,6 @@ func encode(w io.Writer, value interface{}) error {
 	return err
 }
 
-func convertMapToConfig(v map[string]interface{}) (*config.Config, error) {
-	var buf bytes.Buffer
-	if err := json.NewEncoder(&buf).Encode(v); err != nil {
-		return nil, err
-	}
-	var conf config.Config
-	if err := json.NewDecoder(&buf).Decode(&conf); err != nil {
-		return nil, fmt.Errorf("Failure to decode config: %s", err)
-	}
-	return &conf, nil
-}
-
 // load reads given file and returns the read config, or error.
 func load(filename string) (*config.Config, error) {
 	// if nothing is there, fail. User must run 'ipfs init'