[大数据]Disruptor并发＜二＞ _ 秒杀示例

目录

一、秒杀流程

二、代码示例

1. 依赖及表结构

2. 秒杀下单

3. 本地处理队列

4. 事件对象

5. 消费者?

6. 异常处理消费者

7. 事件生产者

8. 创建Disruptor

三、参考资料

一、秒杀流程

二、代码示例

1. 依赖及表结构

<dependency>
    <groupId>com.lmax</groupId>
    <artifactId>disruptor</artifactId>
    <version>3.4.4</version>
</dependency>

// 商品库存表
CREATE TABLE `t_goods_stock`  (
  `id` bigint(4) NOT NULL AUTO_INCREMENT COMMENT '主键ID',
  `goods_id` varchar(16) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL COMMENT '商品ID',
  `stock` bigint(255) NULL DEFAULT NULL COMMENT '库存',
  `price` decimal(8, 2) NULL DEFAULT NULL COMMENT '单价',
  PRIMARY KEY (`id`) USING BTREE
) ENGINE = InnoDB AUTO_INCREMENT = 2 CHARACTER SET = utf8 COLLATE = utf8_general_ci ROW_FORMAT = Dynamic;


// 订单表
CREATE TABLE `t_order`  (
  `id` bigint(64) NOT NULL AUTO_INCREMENT COMMENT '主键',
  `user_id` varchar(64) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL COMMENT '用户ID',
  `goods_id` bigint(20) NULL DEFAULT NULL COMMENT '商品ID',
  `number` int(11) NULL DEFAULT NULL COMMENT '购买数量',
  `price` decimal(8, 2) NULL DEFAULT NULL COMMENT '单价',
  `total` decimal(8, 2) NULL DEFAULT NULL COMMENT '总价',
  `create_by` varchar(64) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL COMMENT '创建人',
  `create_time` datetime(0) NULL DEFAULT NULL COMMENT '创建时间',
  `update_by` varchar(64) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL COMMENT '修改人',
  `update_time` datetime(0) NULL DEFAULT NULL COMMENT '修改时间',
  PRIMARY KEY (`id`) USING BTREE
) ENGINE = InnoDB AUTO_INCREMENT = 61686 CHARACTER SET = utf8 COLLATE = utf8_general_ci ROW_FORMAT = Dynamic;

2. 秒杀下单

a. Contoller层

package com.common.instance.test.controller;

import com.common.instance.test.core.Response;
import com.common.instance.test.service.SeckillService;
import io.swagger.annotations.Api;
import io.swagger.annotations.ApiOperation;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import javax.annotation.Resource;
import java.util.Random;

/**
 * @description 秒杀活动
 * @author tcm
 * @version 1.0.0
 * @date 2021/12/23 15:47
 **/
@RestController
@RequestMapping("/seckill")
@Api(tags = "秒杀活动")
public class SeckillController {

    @Resource
    private SeckillService seckillService;

    @GetMapping("/isSeckillGoods")
    @ApiOperation("用户是否抢到商品")
    public Response<Boolean> isSeckillGoods(String goodsId){
        // 返回结果
        Boolean isSeckill = false;
        try {
            // 用户是否抢到商品
            // 随机用户
            String userId = String.valueOf(System.currentTimeMillis());
            // 随机商品数量
            Random rand = new Random();
            Integer num = rand.nextInt(10) + 1;

            isSeckill = seckillService.isSeckillGoods(userId, goodsId, num);
        } catch (Exception e) {
            e.printStackTrace();
            return Response.error();
        }
        return Response.success(isSeckill);
    }

}

b. Service层

package com.common.instance.test.service.impl;

import com.common.instance.test.dao.TGoodsStockDao;
import com.common.instance.test.disruptor.event.SeckillGoodsEvent;
import com.common.instance.test.disruptor.localQueue.RedisQueue;
import com.common.instance.test.entity.TGoodsStock;
import com.common.instance.test.service.SeckillService;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.stereotype.Service;

import javax.annotation.Resource;
import java.util.Objects;
import java.util.concurrent.TimeUnit;

/**
 * @description 秒杀活动
 * @author tcm
 * @version 1.0.0
 * @date 2021/12/23 15:49
 **/
@Service
public class SeckillServiceImpl implements SeckillService {

    @Resource
    private RedisTemplate<String, Object> redisTemplate;

    @Resource
    private TGoodsStockDao tGoodsStockDao;

    @Override
    public Boolean isSeckillGoods(String userId, String goodsId, Integer num) {
        // 返回结果
        Boolean result = false;

        // 商品秒杀数量
        Long count = redisTemplate.opsForValue().decrement(RedisQueue.SECKILL_KEY + goodsId, num);
        // 查询商品库存，设置值
        if (Objects.nonNull(count) && count < 0 ) {
            TGoodsStock goodsStock = tGoodsStockDao.selectByPrimaryKey(1L);
            if (Objects.nonNull(goodsStock)) {
                count = goodsStock.getStock() - num;
                redisTemplate.opsForValue().set(RedisQueue.SECKILL_KEY + goodsId, count, 1, TimeUnit.DAYS);
            }
        }
        if (Objects.nonNull(count) && count >= 0) {
            // 创建秒杀商品对象事件
            SeckillGoodsEvent seckillGoodsEvent = new SeckillGoodsEvent();
            seckillGoodsEvent.setUserId(userId);
            seckillGoodsEvent.setGoodsId(goodsId);
            seckillGoodsEvent.setNum(num);

            // 保存到等待队列
            redisTemplate.opsForList().leftPush(RedisQueue.WAIT_QUEUE, seckillGoodsEvent);
            result = true;
        }
        return result;
    }

}

3. 本地处理队列

a. 定义Redis队列

package com.common.instance.test.disruptor.localQueue;

import org.springframework.stereotype.Component;

/**
 * @description Redis队列中
 * @author tcm
 * @version 1.0.0
 * @date 2021/12/23 16:26
 **/
public class RedisQueue {

    // 商品秒伤数量前缀
    public static final String SECKILL_KEY = "SECKILL:GOODS_ID:";
    // 商品秒伤数量锁
    public static final String SECKILL_LOCK = "SECKILL:LOCK:";

    // 等待队列
    public static final String WAIT_QUEUE = "SECKILL:QUEUE:WAIT_QUEUE";
    // 正在处理队列
    public static final String PROCESSING_QUEUE = "SECKILL:QUEUE:PROCESSING_QUEUE";
    // 失败队列
    public static final String FAILED_QUEUE = "SECKILL:QUEUE:FAILED_QUEUE";
    // 镜像队列
    public static final String IMAGE_QUEUE = "SECKILL:QUEUE:IMAGE_QUEUE";

}

b. 本地处理队列

package com.common.instance.test.disruptor.localQueue;

import com.alibaba.fastjson.JSON;
import com.common.instance.test.disruptor.event.SeckillGoodsEvent;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.stereotype.Component;

import javax.annotation.PostConstruct;
import javax.annotation.Resource;
import java.util.Objects;
import java.util.concurrent.LinkedBlockingQueue;

/**
 * @description 本地事件队列
 * @author tcm
 * @version 1.0.0
 * @date 2021/12/24 17:09
 **/
@Component
public class MyEventQueue {

    @Resource
    private RedisTemplate<String, Object> redisTemplate;

    // 本地事件队列
    private LinkedBlockingQueue<SeckillGoodsEvent> myEventQueue;
    // 队列最大元素数量
    private int capacity = 100000;

    @PostConstruct
    public void create(){
        createEventQueue();
        getWaitQueue();
    }

    private void createEventQueue(){
        myEventQueue = new LinkedBlockingQueue<>();
    }

    private void getWaitQueue(){
        new Thread(new MyThread()).start();
    }

    public LinkedBlockingQueue<SeckillGoodsEvent> getMyEventQueue() {
        return myEventQueue;
    }

    public void setMyEventQueue(LinkedBlockingQueue<SeckillGoodsEvent> myEventQueue) {
        this.myEventQueue = myEventQueue;
    }

    class MyThread implements Runnable {

        @Override
        public void run() {
            while (true) {
                try {
                    // 判定元素数量是否大于容积
                    if (myEventQueue.size() < capacity) {
                        // 等待队列获取秒杀事件
                        Object o = redisTemplate.opsForList().rightPop(RedisQueue.WAIT_QUEUE);
                        if (Objects.nonNull(o)) {
                            String event = JSON.toJSONString(o);
                            SeckillGoodsEvent seckillGoodsEvent = JSON.parseObject(event, SeckillGoodsEvent.class);

                            // 添加到本地队列中
                            myEventQueue.offer(seckillGoodsEvent);
                            // 添加到正在处理队列中
                            redisTemplate.opsForList().leftPush(RedisQueue.PROCESSING_QUEUE, seckillGoodsEvent);
                            // 添加到镜像队列
                            redisTemplate.opsForList().leftPush(RedisQueue.IMAGE_QUEUE, seckillGoodsEvent);
                        } else {
                            Thread.sleep(1 * 1000);
                        }
                    } else {
                        Thread.sleep(1 * 1000);
                    }
//                    LogUtil.info("myEventQueue size: " + myEventQueue.size());
                } catch (InterruptedException e) {
                    e.printStackTrace();
                    continue;
                }
            }
        }
    }

}

4. 事件对象

package com.common.instance.test.disruptor.event;

import lombok.Data;

/**
 * @description 秒杀商品事件信息
 * @author tcm
 * @version 1.0.0
 * @date 2021/12/23 15:34
 **/
@Data
public class SeckillGoodsEvent {

    // 用户ID
    private String userId;
    // 商品ID
    private String goodsId;
    // 购买商品数量
    private Integer num;
    // 订单ID
    private Long orderId;

}

5. 消费者?

a. 创建订单消费者

package com.common.instance.test.disruptor.consumer;

import com.common.instance.test.dao.TGoodsStockDao;
import com.common.instance.test.dao.TOrderDao;
import com.common.instance.test.disruptor.event.SeckillGoodsEvent;
import com.common.instance.test.entity.TGoodsStock;
import com.common.instance.test.entity.TOrder;
import com.lmax.disruptor.EventHandler;
import org.springframework.stereotype.Component;

import javax.annotation.Resource;
import java.math.BigDecimal;
import java.util.Date;

/**
 * @description 生成订单
 * @author tcm
 * @version 1.0.0
 * @date 2021/12/24 9:49
 **/
@Component
public class CreateOrderHandler implements EventHandler<SeckillGoodsEvent> {

    @Resource
    private TOrderDao tOrderDao;
    @Resource
    private TGoodsStockDao tGoodsStockDao;

    @Override
    public void onEvent(SeckillGoodsEvent seckillGoodsEvent, long sequence, boolean endOfBatch) throws Exception {
        // 获取商品信息
        TGoodsStock tGoodsStock = tGoodsStockDao.selectByPrimaryKey(1L);

        // 组装订单对象
        TOrder order = createOrder(seckillGoodsEvent, tGoodsStock);

        // 保存订单
        tOrderDao.insert(order);

        // 秒杀活动获取订单ID
        seckillGoodsEvent.setOrderId(order.getId());
    }

    // 组装订单对象
    private TOrder createOrder(SeckillGoodsEvent seckillGoodsEvent, TGoodsStock tGoodsStock){
        TOrder order = new TOrder();

        order.setUserId(seckillGoodsEvent.getUserId());
        order.setGoodsId(Long.valueOf(seckillGoodsEvent.getGoodsId()));
        order.setNumber(seckillGoodsEvent.getNum());
        order.setPrice(tGoodsStock.getPrice());
        // 计算总价
        BigDecimal total = new BigDecimal("0");
        total = total.add(order.getPrice().multiply(new BigDecimal(order.getNumber())));
        order.setTotal(total);
        Date date = new Date();
        order.setCreateBy("admin");
        order.setCreateTime(date);
        order.setUpdateBy("admin");
        order.setUpdateTime(date);

        return order;
    }

}

b. 发送订单kafka消息

package com.common.instance.test.disruptor.consumer;

import com.alibaba.fastjson.JSONObject;
import com.common.instance.test.disruptor.event.SeckillGoodsEvent;
import com.lmax.disruptor.EventHandler;
import com.log.util.LogUtil;
import org.springframework.kafka.core.KafkaTemplate;
import org.springframework.kafka.support.SendResult;
import org.springframework.stereotype.Component;
import org.springframework.util.concurrent.ListenableFuture;
import org.springframework.util.concurrent.ListenableFutureCallback;

import javax.annotation.Resource;

/**
 * @description 发送kafka消息
 * @author tcm
 * @version 1.0.0
 * @date 2021/12/24 11:05
 **/
@Component
public class KafkaHandler implements EventHandler<SeckillGoodsEvent> {

    @Resource
    private KafkaTemplate<String, String> kafkaTemplate;

    public static final String TOPIC_TEST = "SeckillGoodsEvent";

    @Override
    public void onEvent(SeckillGoodsEvent seckillGoodsEvent, long sequence, boolean endOfBatch) throws Exception {
        send(seckillGoodsEvent);
    }

    // 发送kafka消息
    public void send(SeckillGoodsEvent seckillGoodsEvent) {
        String obj2String = JSONObject.toJSONString(seckillGoodsEvent);

        // 发送消息
        ListenableFuture<SendResult<String, String>> future = kafkaTemplate.send(TOPIC_TEST, obj2String);
        future.addCallback(new ListenableFutureCallback<SendResult<String, String>>() {
            @Override
            public void onFailure(Throwable throwable) {
                //发送失败的处理
                LogUtil.info(TOPIC_TEST + " - 生产者 发送消息失败：" + throwable.getMessage());
            }

            @Override
            public void onSuccess(SendResult<String, String> stringObjectSendResult) {
                //成功的处理
                LogUtil.info(TOPIC_TEST + " - 生产者 发送消息成功：" + stringObjectSendResult.toString());
            }
        });
    }

}

c. 扣减库存

package com.common.instance.test.disruptor.consumer;

import com.common.instance.test.dao.TGoodsStockDao;
import com.common.instance.test.dao.TOrderDao;
import com.common.instance.test.disruptor.event.SeckillGoodsEvent;
import com.common.instance.test.entity.TGoodsStock;
import com.common.instance.test.entity.TOrder;
import com.lmax.disruptor.EventHandler;
import org.springframework.stereotype.Component;

import javax.annotation.Resource;
import java.util.Objects;

/**
 * @description 扣减库存
 * @author tcm
 * @version 1.0.0
 * @date 2021/12/24 11:08
 **/
@Component
public class ReduceStockHandler implements EventHandler<SeckillGoodsEvent> {

    @Resource
    private TOrderDao tOrderDao;
    @Resource
    private TGoodsStockDao tGoodsStockDao;

    @Override
    public void onEvent(SeckillGoodsEvent event, long sequence, boolean endOfBatch) throws Exception {
        // 获取秒杀订单
        TOrder order = tOrderDao.selectByPrimaryKey(event.getOrderId());
        // 获取商品库存
        TGoodsStock goodsStock = tGoodsStockDao.selectByPrimaryKey(1L);

        if (Objects.nonNull(order) && Objects.nonNull(goodsStock)){
            // 计算库存
            Long stock = goodsStock.getStock() - order.getNumber();
            goodsStock.setStock(stock);
            // 更新库存
            tGoodsStockDao.updateByPrimaryKey(goodsStock);
        }
    }

}

d. 移除正处理队列元素

package com.common.instance.test.disruptor.consumer;

import com.alibaba.fastjson.JSON;
import com.common.instance.test.disruptor.event.SeckillGoodsEvent;
import com.common.instance.test.disruptor.localQueue.RedisQueue;
import com.lmax.disruptor.*;
import com.log.util.LogUtil;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.stereotype.Component;

import javax.annotation.Resource;

/**
 * @description 所有消费处理完，正在处理的秒杀事件移除
 * @author TCM
 * @version 1.0
 * @date 2021/12/25 17:14
 **/
@Component
public class RemoveProcessingQueueHandler implements EventHandler<SeckillGoodsEvent> {

    @Resource
    private RedisTemplate<String, Object> redisTemplate;

    @Override
    public void onEvent(SeckillGoodsEvent seckillGoodsEvent, long l, boolean b) throws Exception {
        // 事件处理完成后，从正在处理队列中移除
        Object event = redisTemplate.opsForList().rightPop(RedisQueue.PROCESSING_QUEUE);
        LogUtil.info( l +  "removeProcessing: " + JSON.toJSONString(event));
    }

}

6. 异常处理消费者

package com.common.instance.test.disruptor.consumer;

import com.alibaba.fastjson.JSON;
import com.common.instance.test.disruptor.event.SeckillGoodsEvent;
import com.common.instance.test.disruptor.localQueue.RedisQueue;
import com.lmax.disruptor.ExceptionHandler;
import com.log.util.LogUtil;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.stereotype.Component;

import javax.annotation.Resource;

/**
 * @description Disruptor异常捕捉
 * @author TCM
 * @version 1.0
 * @date 2021/12/25 19:39
 **/
@Component
public class MyExceptionHandler implements ExceptionHandler<SeckillGoodsEvent> {

    @Resource
    private RedisTemplate<String, Object> redisTemplate;

    @Override
    public void handleEventException(Throwable ex, long sequence, SeckillGoodsEvent seckillGoodsEvent) {
        try {
            // 移除正在处理队列事件
            redisTemplate.opsForList().rightPop(RedisQueue.PROCESSING_QUEUE);
            // 添加到失败队列事件
            redisTemplate.opsForList().leftPush(RedisQueue.FAILED_QUEUE, seckillGoodsEvent);
            // 记录处理异常
            LogUtil.error("MyExceptionHandler.handleEventException()", (Exception) ex);
        } catch (Exception e) {
            LogUtil.error("MyExceptionHandler.handleEventException()",
                    "PROCESSING_QUEUE into FAILED_QUEUE failed: " + JSON.toJSONString(seckillGoodsEvent),
                    e);
        }

    }

    @Override
    public void handleOnStartException(Throwable ex) {
        LogUtil.error("MyExceptionHandler.handleOnStartException()", (Exception) ex);
    }

    @Override
    public void handleOnShutdownException(Throwable ex) {
        LogUtil.error("MyExceptionHandler.handleOnShutdownException()", (Exception) ex);
    }

}

7. 事件生产者

package com.common.instance.test.disruptor.publisher;

import com.alibaba.fastjson.JSON;
import com.common.instance.test.disruptor.event.SeckillGoodsEvent;
import com.common.instance.test.disruptor.localQueue.MyEventQueue;
import com.lmax.disruptor.EventTranslator;
import com.log.util.LogUtil;

import java.util.Objects;

/**
 * @description 将事件发送到RingBuffer
 * @author TCM
 * @version 1.0
 * @date 2021/12/24 22:51
 **/
public class MyEventTranslator implements EventTranslator<SeckillGoodsEvent> {

    // 本地事件队列
    private MyEventQueue myEventQueue;

    public MyEventTranslator(MyEventQueue myEventQueue){
        this.myEventQueue = myEventQueue;
    }

    @Override
    public void translateTo(SeckillGoodsEvent seckillGoodsEvent, long l) {
        // 从本地队列获取事件
        SeckillGoodsEvent event = myEventQueue.getMyEventQueue().poll();
        // 事件属性值赋值
        if (Objects.nonNull(event)){
            seckillGoodsEvent.setUserId(event.getUserId());
            seckillGoodsEvent.setGoodsId(event.getGoodsId());
            seckillGoodsEvent.setNum(event.getNum());
        }

        LogUtil.info(l + " seckillGoodsEvent: " + JSON.toJSONString(seckillGoodsEvent));
    }

}

8. 创建Disruptor

package com.common.instance.test.disruptor;

import com.common.instance.test.disruptor.consumer.*;
import com.common.instance.test.disruptor.event.SeckillGoodsEvent;
import com.common.instance.test.disruptor.localQueue.MyEventQueue;
import com.common.instance.test.disruptor.publisher.MyEventTranslator;
import com.lmax.disruptor.BlockingWaitStrategy;
import com.lmax.disruptor.EventFactory;
import com.lmax.disruptor.dsl.Disruptor;
import com.lmax.disruptor.dsl.EventHandlerGroup;
import com.lmax.disruptor.dsl.ProducerType;
import com.log.util.LogUtil;
import org.springframework.stereotype.Component;

import javax.annotation.PostConstruct;
import javax.annotation.Resource;
import java.util.concurrent.Executors;

/**
 * @description 创建Disruptor并启动
 * @author TCM
 * @version 1.0
 * @date 2021/12/24 21:20
 **/
@Component
public class SeckillDisruptor {

    // 消费者：所有Handler处理异常记录
    @Resource
    private MyExceptionHandler myExceptionHandler;
    // 消费者：创建订单
    @Resource
    private CreateOrderHandler createOrderHandler;
    // 消费者：发送kafka
    @Resource
    private KafkaHandler kafkaHandler;
    // 消费者：扣减库存
    @Resource
    private ReduceStockHandler reduceStockHandler;
    // 消费者：移除正在处理的秒杀事件
    @Resource
    private RemoveProcessingQueueHandler removeProcessingQueueHandler;

    @Resource
    private MyEventQueue myEventQueue;

    private Disruptor<SeckillGoodsEvent> disruptor;

    @PostConstruct
    public void init(){
        LogUtil.info("SeckillDisruptor init");
        // 创建Disruptor
        disruptor = createDisruptor();
        // 启动
        new Thread(new StartDisruptorThread()).start();
    }

    // 创建Disruptor
    public Disruptor<SeckillGoodsEvent> createDisruptor(){
        // 创建Disruptor
        Disruptor<SeckillGoodsEvent> disruptor = new Disruptor<SeckillGoodsEvent>(
                // 预填充RingBuffer
                new EventFactory(){
                    @Override
                    public Object newInstance() {
                        return new SeckillGoodsEvent();
                    }
                },
                // RingBuffer的大小（必须为2的N次方）
                4096,
                // 线程池处理
                Executors.newWorkStealingPool(256),
                // 生成类型：SINGLE（单生产者）、MULTI（多生产者）
                ProducerType.SINGLE,
                // 等待策略
                new BlockingWaitStrategy());

        // 消费异常处理
        disruptor.setDefaultExceptionHandler(myExceptionHandler);
        // 消费者
        EventHandlerGroup<SeckillGoodsEvent> handlerGroup = disruptor.handleEventsWith(createOrderHandler);
        handlerGroup.then(kafkaHandler, reduceStockHandler);
        handlerGroup.then(removeProcessingQueueHandler);

        return disruptor;
    }

    class StartDisruptorThread implements Runnable {

        @Override
        public void run() {
            disruptor.start();
            while (true) {
                try {
                    // 本地队列没有秒杀事件，休眠50ms
                    if (myEventQueue.getMyEventQueue().isEmpty()) {
//                        LogUtil.info("本地事件队列没有可处理秒杀事件" + Thread.currentThread().getName());
                        Thread.sleep(1 * 50);
                        continue;
                    }

                    // 生产者
                    MyEventTranslator myEventTranslator = new MyEventTranslator(myEventQueue);
                    disruptor.publishEvent(myEventTranslator);
                } catch (Exception e) {
                    e.printStackTrace();
                    continue;
                }
            }
        }

    }

}

三、参考资料

Disruptor 系列（二）使用场景 - 走看看

disruptor模拟高速处理大规模订单类业务场景_congge-CSDN博客

SpringBoot - 并发框架Disruptor使用详解2（多生产者、多消费者、消费者依赖关系）

使用Disruptor完成多个消费者不重复消费消息_tianyaleixiaowu的专栏-CSDN博客_disruptor 多消费者