Abstract redis access to a seperate interface

[kageurufu]

class IdempotentStorageIterface(object):
    def get(self, key): pass
    def set(self, key): pass
    def atomic_set(self, key): pass
    def subscribe(self, key): pass
    def get_messages(self, timeout=None): pass
    def notify(self, key, message): pass
    def close(self): pass

atomic_set can be implemented in redis using NX {E,P}X

close should cleanly end any subscriptions, and close any sockets or connections that were created for this request. Pooling should be preferred over connect/close, and close should release the connection to the pool in that case. Redis uses StrictRedis.from_url which is a ConnectionPool instance.