timer_queue.py 文件源码

def add_timer(self, callback, when, interval, ident=None):
        ''' Add timer to the queue.

        :param callback: Arbitrary callable object.
        :type callback: ``callable object``
        :param when: The first expiration time, seconds since epoch.
        :type when: ``integer``
        :param interval: Timer interval, if equals 0, one time timer, otherwise
            the timer will be periodically executed
        :type interval: ``integer``
        :param ident: (optional) Timer identity.
        :type ident:  ``integer``
        :returns: A timer object which should not be manipulated directly by
            clients. Used to delete/update the timer
        '''

        with self._lock:
            timer = self._timers.add_timer(callback, when, interval, ident)
        self._wakeup()
        return timer