add auth for future https srever and cfgHandler to load configuration

cfg/cfg.go

@@ -0,0 +1,63 @@
+package cfg
+
+import (
+	"fmt"
+	"os"
+	"path"
+
+	"gopkg.in/yaml.v3"
+)
+
+type Cfg struct {
+	Name string
+	Dir  string
+}
+
+// Initializes new config handler
+// dir is config directory from working dir on
+// name is filename, file extention is automatically added '.cfg'
+// file is in yaml format
+// if file exists it will read its content in to the driver
+func NewCfgHandler(dir, name string) *Cfg {
+	return &Cfg{
+		Dir:  dir,
+		Name: name,
+	}
+}
+
+func (c *Cfg) SaveCfg(data any) error {
+	if _, err := os.Stat(c.Dir); err != nil {
+		if err := os.MkdirAll(c.Dir, 0666); err != nil {
+			return err
+		}
+	}
+	f, err := os.Create(path.Join(c.Dir, c.Name) + ".cfg")
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+
+	encoder := yaml.NewEncoder(f)
+	encoder.SetIndent(2)
+
+	if err := encoder.Encode(data); err != nil {
+		return err
+	}
+	encoder.Close()
+
+	return nil
+}
+
+func (c *Cfg) LoadCfg(data any) error {
+	p := path.Join(c.Dir, c.Name) + ".cfg"
+	if _, err := os.Stat(p); err != nil {
+		return fmt.Errorf("no configuration file: '%s' found", p)
+	}
+
+	b, err := os.ReadFile(p)
+	if err != nil {
+		return err
+	}
+
+	return yaml.Unmarshal(b, data)
+}