from datetime import datetime
def timeguard(time_interval, default=None):
"""Run decorated function not often than time_interval.
If the function is called more often than time_interval
run the default function instead if it's not None.
>>> import time
>>> from datetime import timedelta
Let's define a test class first:
>>> class TimeGuardTest(object):
...
... def dot(self):
... print ".",
...
... @timeguard(timedelta(seconds=3), default=dot)
... def plus(self):
... print "+",
...
... @timeguard(timedelta(seconds=2))
... def minus(self):
... print "-",
...
... def run(self):
... for i in range(6):
... self.plus()
... self.minus()
... time.sleep(1.1)
Now run the test and see results:
>>> test = TimeGuardTest()
>>> test.run()
+ - . . - + . - .
"""
def decorator(function):
# For first time always run the function
function.__last_run = datetime.min
def guard(*args, **kwargs):
now = datetime.now()
if now - function.__last_run >= time_interval:
function.__last_run = now
return function(*args, **kwargs)
elif default is not None:
return default(*args, **kwargs)
return guard
return decorator
if __name__ == "__main__":
import doctest
doctest.testmod()
