如何在Python中实现watchdog定时器？

How to implement a watchdog timer in Python?

我想在Python中实现一个简单的看门狗计时器，它有两个用例：

看门狗确保函数的执行时间不超过x秒。
看门狗确保某些定期执行的函数确实至少每y秒执行一次。

我该怎么做？

只需发布我自己的解决方案：

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from threading import Timer

class Watchdog:
def __init__(self, timeout, userHandler=None): # timeout in seconds
self.timeout = timeout
self.handler = userHandler if userHandler is not None else self.defaultHandler
self.timer = Timer(self.timeout, self.handler)
self.timer.start()

def reset(self):
self.timer.cancel()
self.timer = Timer(self.timeout, self.handler)
self.timer.start()

def stop(self):
self.timer.cancel()

def defaultHandler(self):
raise self

如果要确保函数在不到x秒内完成，请使用：

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watchdog = Watchdog(x)
try:
# do something that might take too long
except Watchdog:
# handle watchdog error
watchdog.stop()

用法：如果您经常执行某项操作，并且希望确保至少每隔y秒执行一次：

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import sys

def myHandler():
print"Whoa! Watchdog expired. Holy heavens!"
sys.exit()

watchdog = Watchdog(y, myHandler)

def doSomethingRegularly():
# make sure you do not return in here or call watchdog.reset() before returning
watchdog.reset()