Redis Cluster Router

This page gives you introductions on redis router for cluster.

CRC32Hash Router

Router that just routes commands to redis node based on crc32 % node_num. For more details check out RedisCRC32HashRouter.

ConsistentHash Router

Router that routes to redis based on consistent hashing algorithm. For more details check out RedisConsistentHashRouter.

Build Your Own Router

Subclass BaseRedisRouter, implement get_host_for_key().

Here is the builtin CRC32 router:

from binascii import crc32

class RedisCRC32HashRouter(BaseRedisRouter):
    """Use crc32 for hash partitioning."""

    def __init__(self, hosts):
        BaseRedisRouter.__init__(self, hosts)
        self._sorted_host_names = sorted(hosts.keys())

    def get_host_for_key(self, key):
        if isinstance(key, unicode):
            key = key.encode('utf-8')
            key = str(key)
        pos = crc32(key) % len(self._sorted_host_names)
        return self._sorted_host_names[pos]