function cache

function_cache.py

__author__ = 'sanpingz'
__doc__ = '''Fucntion cache based on decorator, support expire and args'''
import time

cache = dict()


def cached(expire=0):
	def _deco(func):
		def __deco(*args, **kwargs):
			ch = cache.get(func.__name__) or {}
			if  ch and (
				(expire > 0 and time.time() - ch.get('time') < expire) or 
				(expire <= 0 and args == ch.get('args') and kwargs == ch.get('kwargs'))
				):
				return ch.get('return')

			ch['return'] = func(*args, **kwargs)
			ch['time'] = time.time()
			ch['args'] = args
			ch['kwargs'] = kwargs
			cache[func.__name__] = ch
			return ch.get('return')
		return __deco
	return _deco


@cached(expire=3)
def foo(*args, **kwargs):
	time.sleep(3)
	return time.time()


@cached()
def bar(a, k=1):
	time.sleep(3)
	return str(a)+str(k)


if __name__ == '__main__':
	print foo()
	print foo()
	time.sleep(3)
	print foo()

	print bar("a")
	print bar("a")
	print bar("b")