Add json config reader/writer

pkg/utils/config/config.go

@@ -0,0 +1,97 @@
+package config
+
+import (
+	"encoding/json"
+	"os"
+	"path"
+	"sync"
+
+	"github.com/minio-io/minio/pkg/utils/helpers"
+)
+
+type Config struct {
+	configPath string
+	configFile string
+	configLock *sync.RWMutex
+	Users      map[string]User
+}
+
+type User struct {
+	Name      string
+	AccessKey string
+	SecretKey string
+}
+
+func (c *Config) SetupConfig() error {
+	confPath := path.Join(helpers.HomeDir(), ".minio")
+	if err := os.MkdirAll(confPath, os.ModeDir); err != nil {
+		return err
+	}
+
+	c.configPath = confPath
+	c.configFile = path.Join(c.configPath, "config.json")
+	if _, err := os.Stat(c.configFile); os.IsNotExist(err) {
+		_, err = os.Create(c.configFile)
+		if err != nil {
+			return err
+		}
+	}
+
+	c.configLock = new(sync.RWMutex)
+	return nil
+}
+
+func (c *Config) GetConfigPath() string {
+	return c.configPath
+}
+
+func (c *Config) AddUser(user User) {
+	var currentUsers map[string]User
+	if len(c.Users) == 0 {
+		currentUsers = make(map[string]User)
+	} else {
+		currentUsers = c.Users
+	}
+	currentUsers[user.AccessKey] = user
+	c.Users = currentUsers
+}
+
+func (c *Config) WriteConfig() error {
+	var file *os.File
+	var err error
+
+	c.configLock.Lock()
+	defer c.configLock.Unlock()
+	file, err = os.OpenFile(c.configFile, os.O_WRONLY, 0666)
+	defer file.Close()
+	if err != nil {
+		return err
+	}
+
+	encoder := json.NewEncoder(file)
+	encoder.Encode(c.Users)
+	return nil
+}
+
+func (c *Config) ReadConfig() error {
+	var file *os.File
+	var err error
+
+	c.configLock.RLock()
+	defer c.configLock.RUnlock()
+
+	file, err = os.OpenFile(c.configFile, os.O_RDONLY, 0666)
+	defer file.Close()
+	if err != nil {
+		return err
+	}
+
+	users := make(map[string]User)
+	decoder := json.NewDecoder(file)
+	err = decoder.Decode(&users)
+	if err != nil {
+		return err
+	}
+	c.Users = users
+	return nil
+}