go(utils): add helper function to get config file handler

go/utils/config.go

@@ -0,0 +1,24 @@
+package utils
+
+import (
+	"errors"
+	"fmt"
+	"os"
+)
+
+func GetConfigFile(name string) (*os.File, error) {
+	_, err := os.Stat(name)
+	if err != nil {
+		if errors.Is(err, os.ErrNotExist) {
+			//create file
+			file, err := os.Create(name)
+			if err != nil {
+				return nil, fmt.Errorf("fail to create config file: %w", err)
+			}
+			return file, err
+		} else {
+			return nil, err
+		}
+	}
+	return os.OpenFile(name, os.O_RDWR, 0644)
+}