springboot +rabbitmq+redis实现秒杀示例
目录
- 实现说明
- 1、工具准备
- 2、数据表
- 3、pom
- 4、代码结构
- 5、配置config
- 6、订单业务层
- 7、redis实现层
- 8、mq实现层
- 9、redis模拟初始化库存量
- 10、controller控制层
- 11、测试
- 12、测试结果
实现说明
这里的核心在于如何在大并发的情况下保证数据库能扛得住压力,因为大并发的瓶颈在于数据库。如果用户的请求直接从前端传到数据库,显然,数据库是无法承受几十万上百万甚至上千万的并发量的。因此,我们能做的只能是减少对数据库的访问。例如,前端发出了100万个请求,通过我们的处理,最终只有10个会访问数据库,这样就会大大提升系统性能。再针对秒杀这种场景,因为秒杀商品的数量是有限的,因此采用上述实现方案。
假如,某个商品可秒杀的数量是10,那么在秒杀活动开始之前,把商品的ID和数量加载到Redis缓存。当服务端收到请求时,首先预减Redis中的数量,如果数量减到小于0时,那么随后的访问直接返回秒杀失败的信息。也就是说,最终只有10个请求会去访问数据库。
如果商品数量比较多,比如1万件商品参与秒杀,那么就有1万*10=10万个请求并发去访问数据库,数据库的压力还是会很大。这里就用到了另外一个非常重要的组件:消息队列。我们不是把请求直接去访问数据库,而是先把请求写到消息队列中,做一个缓存,然后再去慢慢的更新数据库。这样做之后,前端用户的请求可能不会立即得到响应是成功还是失败,很可能得到的是一个排队中的返回值,这个时候,需要客户端去服务端轮询,因为我们不能保证一定就秒杀成功了。当服务端出队,生成订单以后,把用户ID和商品ID写到缓存中,来应对客户端的轮询就可以了。这样处理以后,我们的应用是可以很简单的进行分布式横向扩展的,以应对更大的并发。当然,秒杀系统还有很多要处理的事情,比如限流防刷、分布式Session等等。
1、工具准备
rabbitmq安装:https://www.jb51.net/article/253706.htm
界面地址:http://localhost:15672/#/
用户名 guest
密码 guest
redis安装:https://www.jb51.net/article/145704.htm
jmeter安装:https://www.jb51.net/article/232152.htm
2、数据表
商品表
-- ---------------------------- -- Table structure for stock -- ---------------------------- DROP TABLE IF EXISTS `stock`; CREATE TABLE `stock` ( `id` int(11) unsigned NOT NULL AUTO_INCREMENT, `name` varchar(50) NOT NULL DEFAULT '' COMMENT '名称', `count` int(11) NOT NULL COMMENT '库存', `sale` int(11) NOT NULL COMMENT '已售', `version` int(11) NOT NULL COMMENT '乐观锁,版本号', PRIMARY KEY (`id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8;
订单表
-- ---------------------------- -- Table structure for stock_order -- ---------------------------- DROP TABLE IF EXISTS `stock_order`; CREATE TABLE `stock_order` ( `id` int(11) unsigned NOT NULL AUTO_INCREMENT, `sid` int(11) NOT NULL COMMENT '库存ID', `name` varchar(30) NOT NULL DEFAULT '' COMMENT '商品名称', `create_time` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP COMMENT '创建时间', PRIMARY KEY (`id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8;
3、pom
<dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-amqp</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-data-redis</artifactId> </dependency>
4、代码结构
5、配置config
mq配置
package com.yy.msserver.config; import org.springframework.amqp.core.Binding; import org.springframework.amqp.core.BindingBuilder; import org.springframework.amqp.core.Exchange; import org.springframework.amqp.core.ExchangeBuilder; import org.springframework.amqp.core.Queue; import org.springframework.amqp.support.converter.Jackson2JsonMessageConverter; import org.springframework.amqp.support.converter.MessageConverter; import org.springframework.context.annotation.Bean; import org.springframework.context.annotation.Configuration; /** * @author code * @Date 2022/6/27 14:03 * Description rabbitmq config * Version 1.0 */ @Configuration public class MyRabbitMQConfig { //库存交换机 public static final String STORY_EXCHANGE = "STORY_EXCHANGE"; //订单交换机 public static final String ORDER_EXCHANGE = "ORDER_EXCHANGE"; //库存队列 public static final String STORY_QUEUE = "STORY_QUEUE"; //订单队列 public static final String ORDER_QUEUE = "ORDER_QUEUE"; //库存路由键 public static final String STORY_ROUTING_KEY = "STORY_ROUTING_KEY"; //订单路由键 public static final String ORDER_ROUTING_KEY = "ORDER_ROUTING_KEY"; @Bean public MessageConverter messageConverter() { return new Jackson2JsonMessageConverter(); } //创建库存交换机 @Bean public Exchange getStoryExchange() { return ExchangeBuilder.directExchange(STORY_EXCHANGE).durable(true).build(); } //创建库存队列 @Bean public Queue getStoryQueue() { return new Queue(STORY_QUEUE); } //库存交换机和库存队列绑定 @Bean public Binding bindStory() { return BindingBuilder.bind(getStoryQueue()).to(getStoryExchange()).with(STORY_ROUTING_KEY).noargs(); } //创建订单队列 @Bean public Queue getOrderQueue() { return new Queue(ORDER_QUEUE); } //创建订单交换机 @Bean public Exchange getOrderExchange() { return ExchangeBuilder.directExchange(ORDER_EXCHANGE).durable(true).build(); } //订单队列与订单交换机进行绑定 @Bean public Binding bindOrder() { return BindingBuilder.bind(getOrderQueue()).to(getOrderExchange()).with(ORDER_ROUTING_KEY).noargs(); } }
redis配置
package com.yy.msserver.config; /** * @author code * @Date 2022/6/27 14:06 * Description redis config * Version 1.0 */ import org.springframework.context.annotation.Bean; import org.springframework.context.annotation.Configuration; import org.springframework.data.redis.connection.RedisConnectionFactory; import org.springframework.data.redis.core.RedisTemplate; import org.springframework.data.redis.serializer.GenericJackson2JsonRedisSerializer; import org.springframework.data.redis.serializer.StringRedisSerializer; /** * @author code *@Date 2022/6/27 14:05 *Description redis config *Version 1.0 */ @Configuration public class RedisConfig { // 配置redis得配置详解 @Bean public RedisTemplate<String, Object> redisTemplate(RedisConnectionFactory redisConnectionFactory) { RedisTemplate<String, Object> template = new RedisTemplate<String, Object>(); template.setConnectionFactory(redisConnectionFactory); template.setKeySerializer(new StringRedisSerializer()); template.setValueSerializer(new GenericJackson2JsonRedisSerializer()); template.setHashKeySerializer(new GenericJackson2JsonRedisSerializer()); template.setHashValueSerializer(new GenericJackson2JsonRedisSerializer()); template.afterPropertiesSet(); return template; } }
6、订单业务层
接口层
package com.yy.msserver.service; import com.yy.msserver.model.vo.Stock; /** * @author code * @Date 2022/6/24 9:25 * Description 订单接口 * Version 1.0 */ public interface StockOrderService { public Integer createOrder(Integer id); public void decrByStock(Integer id); }
实现层
package com.yy.msserver.service.impl; import com.yy.msserver.dao.StockMapper; import com.yy.msserver.dao.StockOrderMapper; import com.yy.msserver.model.vo.Stock; import com.yy.msserver.model.vo.StockOrder; import com.yy.msserver.service.StockOrderService; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Service; import org.springframework.transaction.annotation.Transactional; import java.util.Date; /** * @author code * @Date 2022/6/24 9:25 * Description 订单实现 * Version 1.0 */ @Service public class StockOrderServiceImpl implements StockOrderService { @Autowired private StockOrderMapper stockOrderMapper; @Autowired private StockMapper stockMapper; @Override @Transactional(rollbackFor = Exception.class) public Integer createOrder(Integer id) { //校验库存 Stock stock = checkStock(id); // if(stock.getCount()>0){ // System.out.println("当前库存:" + stock.getCount()); // //扣库存 // if(updateSale(stock) == 1){ // // }else { // return 0; // } // } // return 0; return createOrder(stock); } @Override public void decrByStock(Integer id){ //校验库存 Stock stock = checkStock(id); if(stock.getCount()>0){ System.out.println("当前库存:" + stock.getCount()); //扣库存 updateSale(stock); } } //校验库存 private Stock checkStock(Integer id) { return stockMapper.checkStock(id); } //扣库存 private int updateSale(Stock stock){ return stockMapper.updateSale(stock); } //下订单 private Integer createOrder(Stock stock){ StockOrder order = new StockOrder(); order.setSid(stock.getId()); order.setCreateTime(new Date()); order.setName(stock.getName()); stockOrderMapper.createOrder(order); return order.getId(); } }
7、redis实现层
package com.yy.msserver.service; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.data.redis.core.RedisTemplate; import org.springframework.stereotype.Service; import java.util.Date; import java.util.concurrent.TimeUnit; /** * @author code * @Date 2022/6/27 17:25 * Description redis * Version 1.0 */ @Service public class RedisService { @Autowired private RedisTemplate<String, Object> redisTemplate; /** * 设置String键值对 * @param key * @param value * @param millis */ public void put(String key, Object value, long millis) { redisTemplate.opsForValue().set(key, value, millis, TimeUnit.MINUTES); } public void putForHash(String objectKey, String hkey, String value) { redisTemplate.opsForHash().put(objectKey, hkey, value); } public <T> T get(String key, Class<T> type) { return (T) redisTemplate.boundValueOps(key).get(); } public void remove(String key) { redisTemplate.delete(key); } public boolean expire(String key, long millis) { return redisTemplate.expire(key, millis, TimeUnit.MILLISECONDS); } public boolean persist(String key) { return redisTemplate.hasKey(key); } public String getString(String key) { return (String) redisTemplate.opsForValue().get(key); } public Integer getInteger(String key) { return (Integer) redisTemplate.opsForValue().get(key); } public Long getLong(String key) { return (Long) redisTemplate.opsForValue().get(key); } public Date getDate(String key) { return (Date) redisTemplate.opsForValue().get(key); } /** * 对指定key的键值减一 * @param key * @return */ public Long decrBy(String key) { return redisTemplate.opsForValue().decrement(key); } }
8、mq实现层
减库存
package com.yy.msserver.service; import com.yy.msserver.config.MyRabbitMQConfig; import lombok.extern.slf4j.Slf4j; import org.springframework.amqp.rabbit.annotation.RabbitListener; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Service; /** * @author code * @Date 2022/6/27 15:22 * Description mq商品信息 * Version 1.0 */ @Slf4j @Service public class MQStockService { @Autowired private StockOrderService stockService; /** * 监听库存消息队列,并消费 * @param id */ @RabbitListener(queues = MyRabbitMQConfig.STORY_QUEUE) public void decrByStock(Integer id) { /** * 调用数据库service给数据库对应商品库存减一 */ log.info("减库存"); stockService.decrByStock(id); } }
下订单
package com.yy.msserver.service; import com.yy.msserver.config.MyRabbitMQConfig; import lombok.extern.slf4j.Slf4j; import org.springframework.amqp.rabbit.annotation.RabbitListener; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Service; /** * @author code * @Date 2022/6/27 15:19 * Description mq 订单队列 * Version 1.0 */ @Service @Slf4j public class MQOrderService { @Autowired private StockOrderService orderService; /** * 监听订单消息队列,并消费 * * @param id */ @RabbitListener(queues = MyRabbitMQConfig.ORDER_QUEUE) public void createOrder(Integer id) { log.info("收到订单消息"); orderService.createOrder(id); } }
9、redis模拟初始化库存量
package com.yy.msserver.config; import com.yy.msserver.service.RedisService; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.boot.ApplicationArguments; import org.springframework.stereotype.Component; import javax.annotation.PostConstruct; /** * @author code * @Date 2022/6/29 14:08 * Description 初始化 * Version 1.0 */ @Component public class InitConfig { @Autowired private RedisService redisService; /** * redis初始化商品的库存量和信息 * @param * @throws Exception */ @PostConstruct public void init() { redisService.put("1", 10, 20); } }
10、controller控制层
/** * 使用redis+消息队列进行秒杀实现 * * @param id 商品id * @return */ @GetMapping( value = "/sec",produces = "application/json;charset=utf-8") @ResponseBody public String sec(@RequestParam(value = "id") int id) { String message = null; //调用redis给相应商品库存量减一 Long decrByResult = redisService.decrBy(id+""); if (decrByResult >= 0) { /** * 说明该商品的库存量有剩余,可以进行下订单操作 */ //发消息给库存消息队列,将库存数据减一 rabbitTemplate.convertAndSend(MyRabbitMQConfig.STORY_EXCHANGE, MyRabbitMQConfig.STORY_ROUTING_KEY, id); //发消息给订单消息队列,创建订单 rabbitTemplate.convertAndSend(MyRabbitMQConfig.ORDER_EXCHANGE, MyRabbitMQConfig.ORDER_ROUTING_KEY, id); message = "商品" + id + "秒杀成功"; } else { /** * 说明该商品的库存量没有剩余,直接返回秒杀失败的消息给用户 */ message ="商品" + id + "秒杀商品的库存量没有剩余,秒杀结束"; } return message; }
11、测试
新建线程组——新建取样器(http请求)——新建查看结果树
12、测试结果
到此这篇关于springboot +rabbitmq+redis实现秒杀的文章就介绍到这了,更多相关springboot rabbitmq redis秒杀内容请搜索我们以前的文章或继续浏览下面的相关文章希望大家以后多多支持我们!