python redis客户端使用lua脚本

#!/usr/bin/python
# -*- coding: utf-8 -*-
import redis

r = redis.Redis("127.0.0.1")

lua = """
local key = KEYS[1]
local field = ARGV[1]
local timestamp_new = ARGV[2]

-- get timestamp of the key in redis
local timestamp_old = redis.call(‘hget‘, key, field)

-- if timestamp_old == nil, it means the key is not exist
if timestamp_old == nil or timestamp_new > timestamp_old then
    redis.call(‘hset‘, key, field, timestamp_new)
end
"""

cmd = r.register_script(lua)
res = cmd(keys=[‘meterdata_36118_plab_current‘], args=[‘time‘, 1533299183])  # 关键字参数client可以设置执行lua脚本的client instance, 也可以指定其为pipeline
print res