最近需要对一个接口基于用户进行限流,简单粗暴的固定窗口限流,10s内只允许调3次
一种是直接在JAVA中做逻辑判断
另一种是 通过lua脚本进行实现,故对lua脚本小试牛刀
1. 在JAVA里直接实现
2.通过lua脚本实现
编写lua脚本,把lua脚本放在resources目录下。
add_fav_limit_rate.lua
local times = redis.call('incr',KEYS[1])
if times == 1 then
redis.call('expire',KEYS[1], tonumber(ARGV[1]))
end
if times > tonumber(ARGV[2]) then
return 0
end
return 1
JAVA实现代码
// {"limitTime": 10,"limitUnit": "SECONDS","limitCnt": 3}
String rule = PropertyConfigurer.getNSString("application", "limit.addFav.rule");
JSONObject jsonObject = JSONObject.parseObject(rule);
Integer limitTime = jsonObject.getInteger("limitTime");
Integer limitCnt = jsonObject.getInteger("limitCnt");
RedisTemplate redisTemplate =
RedisTemplateUtil.getRedisTemplateByResourceName(
RedisConstants.ORCHESTRATOR_SERVICE_RESOURCE);
String redisKey = RedisConstants.LIMIT_ADDFAV_KEY_PREFIX + userId;
DefaultRedisScript<Boolean> redisScript = new DefaultRedisScript<>();
redisScript.setResultType(Boolean.class);
redisScript.setScriptSource(
new ResourceScriptSource(new ClassPathResource("script/add_fav_limit_rate.lua")));
List<String> keys = Lists.newArrayList(redisKey);
Boolean result = (Boolean) redisTemplate.execute(redisScript, keys, limitTime, limitCnt);
return result;