dkim010/ring

Generic cache decorator with built-in memcache & redis + asyncio support.

Ring - The ultimate cache interface.

asyncio support!

Take an explicit but fully automated cache. Ring decorators convert your functions to cached version of them, with extra control methods.

Function cache

import ring
import memcache
import requests

mc = memcache.Client(['127.0.0.1:11211'])

# working for mc, expire in 60sec
@ring.func.memcache(mc, time=60)
def get_url(url):
    return requests.get(url).content

# normal way - it is cached
data = get_url('http://example.com')
# delete the cache
get_url.delete('http://example.com')
# get cached data or None
data_or_none = get_url.get('http://example.com')

# get internal cache key
key = get_url.key('http://example.com')
# and access directly to the backend
direct_data = mc.get(key)

Method cache

import ring
import redis

rc = redis.StrictRedis()

class User(dict):
    def __ring_key__(self):
        return self['id']

    # working for rc, no expiration
    # using json coder for non-bytes cache data
    @ring.func.redis(rc, coder='json')
    def data(self):
        return self.copy()

    # parameters are also ok!
    @ring.func.redis(rc, coder='json')
    def child(self, child_id):
        return {'user_id': self['id'], 'child_id': child_id}

user = User(id=42, name='Ring')

# create and get cache
user_data = user.data()  # cached
user['name'] = 'Ding'
# still cached
cached_data = user.data()
assert user_data == cached_data
# refresh
updated_data = user.data.update()
assert user_data != updated_data

# id is the cache key so...
user2 = User(id=42)
# still hitting the same cache
assert user_data == user2.data()