redis+lua实现分布式锁

lock脚本:lock.lua

-- Set a lock
--  若是获取锁成功，则返回 1
local key     = KEYS[1]
local content = KEYS[2]
local ttl     = ARGV[1]
local lockSet = redis.call('setnx', key, content)
if lockSet == 1 then
  redis.call('pexpire', key, ttl) 
else 
  -- 若是value相同，则认为是同一个线程的请求，则认为重入锁
  local value = redis.call('get', key)
  if(value == content) then
    lockSet = 1;
    redis.call('pexpire', key, ttl)
  end
end
return lockSet

•  

unlock脚本: unlock.lua

-- unlock key
local key     = KEYS[1]
local content = KEYS[2]
local value = redis.call('get', key)
if value == content then( 
  return redis.call('del', key);
end
return 0