関数をRedisでキャッシュするためのデコレータ

redis_cache_decorator.py

# coding: utf-8

from __future__ import absolute_import, division, print_function

import pickle

import functools
import redis


def cache(expire_time=1200):
    """
    @param expire_time キャッシュ時間 sec
    """
    def decorator(function):
        @functools.wraps(function)
        def wrapper(*args, **kwargs):
            key = 'c:%s:%s:%s' % (function.__name__, str(args), str(kwargs))
            slave = redis.Redis(host=REDIS_SLAVES_HOST)
            saved_value = slave.get(key)
            if saved_value:
                return pickle.loads(saved_value)
            else:
                value = function(*args, **kwargs)
                if value is not None:
                    master = redis.Redis(host=REDIS_MASTER_HOST)
                    master.setex(key, pickle.dumps(value), expire_time)
            return value
        return wrapper
    return decorator