ils-video-recorder:fix None exception

ils_common_video/utils/isc_client.py

@@ -135,7 +135,8 @@ class HikVisionClient(object):
         log.info('requests body: {}'.format(body))
         expired_time = datetime.now() + timedelta(minutes=5)
         res = self._request(uri, body)
-        if len(res.get('url')) == 0:
+        if not res.get('url') or len(res.get('url')) == 0:
+            log.error("get_cameras_playback_urls,camera point index:%s result :%s", camera_index_code, json.dumps(res))
             return {}
         event = {
             'stream_url': {