fix space check

src/user.py

@@ -319,7 +319,10 @@ def doc_upload(id):
             )
             db.commit()
         except pymysql.Error as _e:
-            error = "未知错误 %s" % (_e)
+            if 'ck_usedspace' in str(_e):
+                error = "空间不够用了，请向管理员申请扩容"
+            else:
+                error = "未知错误 %s" % (_e)
             db.rollback()
     else:
         error = "未收到有效的文件"