1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
|
from binascii import crc_hqx
from redis.typing import EncodedT
# Redis Cluster's key space is divided into 16384 slots.
# For more information see: https://github.com/redis/redis/issues/2576
REDIS_CLUSTER_HASH_SLOTS = 16384
__all__ = ["key_slot", "REDIS_CLUSTER_HASH_SLOTS"]
def key_slot(key: EncodedT, bucket: int = REDIS_CLUSTER_HASH_SLOTS) -> int:
"""Calculate key slot for a given key.
See Keys distribution model in https://redis.io/topics/cluster-spec
:param key - bytes
:param bucket - int
"""
start = key.find(b"{")
if start > -1:
end = key.find(b"}", start + 1)
if end > -1 and end != start + 1:
key = key[start + 1 : end]
return crc_hqx(key, 0) % bucket
|
