LRU cache that invalidates every minute

lru_cache_by_minute.py

from functools import lru_cache, wraps
from datetime import datetime


def lru_cache_by_minute(size):
    """ Decorator that caches the result of `f` during the current minute """

    def real_decorator(f):
        # create a cached function that wraps f but adds a minute argument
        # the size is the number of entries in the cache
        @lru_cache(size)
        @wraps(f)
        def inner(minute, *args, **kwargs):
            return f(*args, **kwargs)

        # calls the cached function with the current minute
        # everytime the current minute changes, the cache is automagically invalidated
        @wraps(inner)
        def outer(*args, **kwargs):
            now_minute = datetime.now().replace(second=0, microsecond=0)
            return inner(now_minute, *args, **kwargs)
        return outer
    return real_decorator