def next_time_range(self):
"""
Calculates next missing range of data
"""
if self.request_couter > 0 and TimeRange.table_empty(self.cur):
return None
if self.request_couter == 0:
if Track.table_empty(self.cur):
timestamp_from = 0
else:
timestamp_from = Track.latest(self.cur).timestamp
return (timestamp_from, self._utc_timestamp_now())
latest = TimeRange.latest(self.cur)
return latest.timestamp_from, latest.timestamp_to
