From 563a368ab09b3b0c317ebbc0dca74c510463f124 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E4=BE=9D=E7=91=AA=E8=B2=93?= <imacat@mail.imacat.idv.tw>
Date: Tue, 7 Jul 2020 21:06:11 +0800
Subject: [PATCH] Fixed UrlBuilder on its string output.

---
 mia_core/utils.py | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/mia_core/utils.py b/mia_core/utils.py
index 0c5387d..20e4e0f 100644
--- a/mia_core/utils.py
+++ b/mia_core/utils.py
@@ -92,7 +92,10 @@ class UrlBuilder:
         return self.del_param(name).add_param(name, value)
 
     def __str__(self):
-        return self.base_path + "&".join([str(x) for x in self.params])
+        if len(self.params) == 0:
+            return self.base_path
+        return self.base_path + "?" + "&".join([
+            str(x) for x in self.params])
 
     class Param:
         """A query parameter.