Repeating Timer in Python

While working on Scheduler [1], I've encountered an inconvenience caused by lack of auto-repeat timer in standard Python API.
In this post I will present RepeatTimer class that features:

• RepeatTimer (as its threading.Timer ancestor) is being executed in a separate thread
• RepeatTimer executes function on its triggering
• Interface provides ability to trigger RepeatTimer immediately, and start new countdown
• Interface provides ability to set new interval that will be applied after upcoming triggering
• cancel method disengage RepeatTimer and kills its thread

Gist below presents the code:

	"""
	Created on 2011-02-10
	@author: Bohdan Mushkevych
	@author: Brian Curtin
	http://code.activestate.com/lists/python-ideas/8982/
	"""
	from datetime import datetime
	import threading
	class RepeatTimer(threading.Thread):
	def __init__(self, interval, callable, args=[], kwargs={}):
	threading.Thread.__init__(self)
	# interval_current shows number of milliseconds in currently triggered <tick>
	self.interval_current = interval
	# interval_new shows number of milliseconds for next <tick>
	self.interval_new = interval
	self.callable = callable
	self.args = args
	self.kwargs = kwargs
	self.event = threading.Event()
	self.event.set()
	self.activation_dt = None
	self.__timer = None
	def run(self):
	while self.event.is_set():
	self.activation_dt = datetime.utcnow()
	self.__timer = threading.Timer(self.interval_new,
	self.callable,
	self.args,
	self.kwargs)
	self.interval_current = self.interval_new
	self.__timer.start()
	self.__timer.join()
	def cancel(self):
	self.event.clear()
	if self.__timer is not None:
	self.__timer.cancel()
	def trigger(self):
	self.callable(*self.args, **self.kwargs)
	if self.__timer is not None:
	self.__timer.cancel()
	def change_interval(self, value):
	self.interval_new = value

view raw repeat_timer.py hosted with ❤ by GitHub

[1] Scheduler at Github
https://github.com/mushkevych/scheduler