Redis Lua指令碼實現ip限流範例

local key = KEYS[1] --限流KEY（一秒一個）
local limit = tonumber(ARGV[1]) --限流大小
local current = tonumber(redis.call('get', key) or "0")
if current + 1 > limit then --如果超出限流大小
    return 0
else --請求數+1，並設定2秒過期
    redis.call("INCRBY", key,"1")
    redis.call("expire", key,"2")
end
return 1

import org.apache.commons.io.FileUtils;
import redis.clients.jedis.Jedis;
import java.io.File;
import java.io.IOException;
import java.net.URISyntaxException;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.CountDownLatch;
public class RedisLimitRateWithLUA {
    public static void main(String[] args) {
        final CountDownLatch latch = new CountDownLatch(1);
        for (int i = 0; i < 7; i++) {
            new Thread(new Runnable() {
                public void run() {
                    try {
                        latch.await();
                        System.out.println("請求是否被執行："+accquire());
                    } catch (Exception e) {
                        e.printStackTrace();
                    }
                }
            }).start();
        }
        latch.countDown();
    }
    public static boolean accquire() throws IOException, URISyntaxException {
        Jedis jedis = new Jedis("127.0.0.1");
        File luaFile = new File(RedisLimitRateWithLUA.class.getResource("/").toURI().getPath() + "limit.lua");
        String luaScript = FileUtils.readFileToString(luaFile);
        String key = "ip:" + System.currentTimeMillis()/1000; // 當前秒
        String limit = "5"; // 最大限制
        List<String> keys = new ArrayList<String>();
        keys.add(key);
        List<String> args = new ArrayList<String>();
        args.add(limit);
        Long result = (Long)(jedis.eval(luaScript, keys, args)); // 執行lua指令碼，傳入引數
        return result == 1;
    }
}

local key = "rate.limit:" .. KEYS[1]
local limit = tonumber(ARGV[1])
local expire_time = ARGV[2]
local is_exists = redis.call("EXISTS", key)
if is_exists == 1 then
    if redis.call("INCR", key) > limit then
        return 0
    else
        return 1
    end
else
    redis.call("SET", key, 1)
    redis.call("EXPIRE", key, expire_time)
    return 1
end