Function redis_keyslot 

pub fn redis_keyslot(key: &[u8]) -> u16

Map a Redis key to its cluster key slot.

$ redis-cli -p 30001 cluster keyslot "8xjx7vWrfPq54mKfFD3Y1CcjjofpnAcQ"
(integer) 5458

assert_eq!(redis_keyslot("8xjx7vWrfPq54mKfFD3Y1CcjjofpnAcQ".as_bytes()), 5458);