retry 'synccheck' if it failed (#417)

Author: RoyXiang

.github/ISSUE_TEMPLATE.md

@@ -18,6 +18,6 @@
 
 > [您的内容]
 
-[document]: https://github.com/soimort/you-get/wiki/FAQ
-[issues]: https://github.com/soimort/you-get/issues
+[document]: http://itchat.readthedocs.io/zh/latest/
+[issues]: https://github.com/littlecodersh/itchat/issues
 [itchatmp]: https://github.com/littlecodersh/itchatmp

itchat/components/login.py

@@ -293,6 +293,7 @@ def sync_check(self):
         '_'        : int(time.time() * 1000),}
     headers = { 'User-Agent' : config.USER_AGENT }
     r = self.s.get(url, params=params, headers=headers, timeout=config.TIMEOUT)
+    r.raise_for_status()
     regx = r'window.synccheck={retcode:"(\d+)",selector:"(\d+)"}'
     pm = re.search(regx, r.text)
     if pm is None or pm.group(1) != '0':