redis-pubsub-dict 0.0.2

RedisDict

Just like a normal dictionary, but networked. Initialisation wont take a dictionary or iterable for now as it need connection and namespace information.

rc = StrictRedisCluster(startup_nodes=[{"host": "redis", "port": "6379"}])
reddict = RedisDict(rc, 'namespace')

# you can set
reddict[1] = 1
reddict[2] = [1,2,3]
reddict['hello'] = 'world'
reddict[('complex',1)] = {'I': {'Am': {'Quite': ['a', 'complex', {'object': {} }]}}}

# get somewhere else
reddict[1]
reddict['1'] # note its the same as reddict[1]
reddict[('complex',1)]
reddict["('complex', 1)"] # the key is str(('complex',1))

# delete
del reddict[1]
# .. ect

PubSubRedisDict

Like RedisDict but will publish key update and delete events to a <namespace>/[update|delete] channel.

redpubsub = PubSubRedisDict(rc, 'namespace')
# ect as before

PubSubCacheManager

Like pylry.WriteThroughCacheManager but updates cache keys from store when it receives a message from the <namespace>/[update|delete] channel.

cache = pylru.lrucache(10) # maybe more than 10
redstore = PubSubRedisDict(rc, 'namespace')
redcache = PubSubCacheManager(redstore, cache)
# ect as before
# see the cache
print dict(redcache.cache)

Further uses

You can hook up RedisDict or PubSubRedisDict to pylru.WriteBackCacheManager to get a Redis backed dictionary which only writes to Redis on ‘flush’ or when the item pops off the lru for write intensive workloads. However a lot more work would need to be done to add the pubsub mechanism as there difficult cases to consider, such as what happens when the cache is dirty and we get notified that the store key is updated?