rabbitmq+redis在优化秒杀商品接口中的使用实例
文章目录
- 基本配置
-
- java rabbitmq config:
- java redis config
- 实体
- 系统初始化
- 消息发送和接收者
- controller
接口优化的思路：（目的：减少数据库访问）
1.系统初始化，把商品库存加载到redis
2.收到请求，redis减库存，如果库存不足则直接返回，否则进入下一步
3.请求入队，立即返回排队中
4.请求出队，生成订单，减少库存（如果订单生成失败则不减去库存）
5.客户端轮询，判断是否秒杀成功
基本配置
#redis
redis.host=10.110.3.62
redis.port=6379
redis.timeout=10
redis.password=123456
redis.poolMaxTotal=1000
redis.poolMaxIdle=500
redis.poolMaxWait=500
#rabbitmq
spring.rabbitmq.host=10.110.3.62
spring.rabbitmq.port=5672
spring.rabbitmq.username=guest
spring.rabbitmq.password=guest
spring.rabbitmq.virtual-host=/
#\u6D88\u8D39\u8005\u6570\u91CF
spring.rabbitmq.listener.simple.concurrency= 10
spring.rabbitmq.listener.simple.max-concurrency= 10
附：Rabbitmq的一些其他配置
spring.rabbitmq.requested-heartbeat: 请求心跳超时时间，0为不指定，如果不指定时间单位默认为妙
spring.rabbitmq.publisher-confirms: 是否启用【发布确认】，默认false
spring.rabbitmq.publisher-returns: 是否启用【发布返回】，默认false
spring.rabbitmq.connection-timeout: 连接超时时间，单位毫秒，0表示永不超时
spring.rabbitmq.listener.type=simple: 容器类型.simple或direct
spring.rabbitmq.listener.simple.auto-startup=true: 是否启动时自动启动容器
spring.rabbitmq.listener.simple.acknowledge-mode: 表示消息确认方式，其有三种配置方式，分别是none、manual和auto；默认auto
spring.rabbitmq.listener.simple.concurrency: 最小的消费者数量
spring.rabbitmq.listener.simple.max-concurrency: 最大的消费者数量
spring.rabbitmq.listener.simple.prefetch: 一个消费者最多可处理的nack消息数量，如果有事务的话，必须大于等于transaction数量.
spring.rabbitmq.listener.simple.transaction-size: 当ack模式为auto时，一个事务（ack间）处理的消息数量，最好是小于等于prefetch的数量.若大于prefetch， 则prefetch将增加到这个值
spring.rabbitmq.listener.simple.default-requeue-rejected: 决定被拒绝的消息是否重新入队；默认是true（与参数acknowledge-mode有关系）
spring.rabbitmq.listener.simple.missing-queues-fatal=true 若容器声明的队列在代理上不可用，是否失败； 或者运行时一个多多个队列被删除，是否停止容器
spring.rabbitmq.listener.simple.idle-event-interval: 发布空闲容器的时间间隔，单位毫秒
spring.rabbitmq.listener.simple.retry.enabled=false: 监听重试是否可用
spring.rabbitmq.listener.simple.retry.max-attempts=3: 最大重试次数
spring.rabbitmq.listener.simple.retry.max-interval=10000ms: 最大重试时间间隔
spring.rabbitmq.listener.simple.retry.initial-interval=1000ms:第一次和第二次尝试传递消息的时间间隔
spring.rabbitmq.listener.simple.retry.multiplier=1: 应用于上一重试间隔的乘数
spring.rabbitmq.listener.simple.retry.stateless=true: 重试时有状态or无状态
spring.rabbitmq.listener.direct.acknowledge-mode= ack模式
spring.rabbitmq.listener.direct.auto-startup=true 是否在启动时自动启动容器
spring.rabbitmq.listener.direct.consumers-per-queue= 每个队列消费者数量.
spring.rabbitmq.listener.direct.default-requeue-rejected= 默认是否将拒绝传送的消息重新入队.
spring.rabbitmq.listener.direct.idle-event-interval= 空闲容器事件发布时间间隔.
spring.rabbitmq.listener.direct.missing-queues-fatal=false若容器声明的队列在代理上不可用，是否失败.
spring.rabbitmq.listener.direct.prefetch= 每个消费者可最大处理的nack消息数量.
spring.rabbitmq.listener.direct.retry.enabled=false 是否启用发布重试机制.
spring.rabbitmq.listener.direct.retry.initial-interval=1000ms # Duration between the first and second attempt to deliver a message.
spring.rabbitmq.listener.direct.retry.max-attempts=3 # Maximum number of attempts to deliver a message.
spring.rabbitmq.listener.direct.retry.max-interval=10000ms # Maximum duration between attempts.
spring.rabbitmq.listener.direct.retry.multiplier=1 # Multiplier to apply to the previous retry interval.
spring.rabbitmq.listener.direct.retry.stateless=true # Whether retries are stateless or stateful.
java rabbitmq config:
@Configuration
public class MQConfig {
public static final String MIAOSHA_QUEUE = "miaosha.queue";
public static final String QUEUE = "queue";
public static final String TOPIC_QUEUE1 = "topic.queue1";
public static final String TOPIC_QUEUE2 = "topic.queue2";
public static final String HEADER_QUEUE = "header.queue";
public static final String TOPIC_EXCHANGE = "topicExchage";
public static final String FANOUT_EXCHANGE = "fanoutxchage";
public static final String HEADERS_EXCHANGE = "headersExchage";
/**
* Direct模式 交换机Exchange
* */
@Bean
public Queue queue() {
return new Queue(QUEUE, true);
}
/**
* Topic模式 交换机Exchange
* */
@Bean
public Queue topicQueue1() {
return new Queue(TOPIC_QUEUE1, true);
}
@Bean
public Queue topicQueue2() {
return new Queue(TOPIC_QUEUE2, true);
}
@Bean
public TopicExchange topicExchage(){
return new TopicExchange(TOPIC_EXCHANGE);
}
@Bean
public Binding topicBinding1() {
return BindingBuilder.bind(topicQueue1()).to(topicExchage()).with("topic.key1");
}
@Bean
public Binding topicBinding2() {
return BindingBuilder.bind(topicQueue2()).to(topicExchage()).with("topic.#");
}
/**
* Fanout模式 交换机Exchange
* */
@Bean
public FanoutExchange fanoutExchage(){
return new FanoutExchange(FANOUT_EXCHANGE);
}
@Bean
public Binding FanoutBinding1() {
return BindingBuilder.bind(topicQueue1()).to(fanoutExchage());
}
@Bean
public Binding FanoutBinding2() {
return BindingBuilder.bind(topicQueue2()).to(fanoutExchage());
}
/**
* Header模式 交换机Exchange
* */
@Bean
public HeadersExchange headersExchage(){
return new HeadersExchange(HEADERS_EXCHANGE);
}
@Bean
public Queue headerQueue1() {
return new Queue(HEADER_QUEUE, true);
}
@Bean
public Binding headerBinding() {
Map<String, Object> map = new HashMap<String, Object>();
map.put("header1", "value1");
map.put("header2", "value2");
return BindingBuilder.bind(headerQueue1()).to(headersExchage()).whereAll(map).match();
}
}
java redis config
redis连接工厂：
@Service
public class RedisPoolFactory {
@Autowired
RedisConfig redisConfig;
@Bean
public JedisPool JedisPoolFactory() {
JedisPoolConfig poolConfig = new JedisPoolConfig();
poolConfig.setMaxIdle(redisConfig.getPoolMaxIdle());
poolConfig.setMaxTotal(redisConfig.getPoolMaxTotal());
poolConfig.setMaxWaitMillis(redisConfig.getPoolMaxWait() * 1000);
JedisPool jp = new JedisPool(poolConfig, redisConfig.getHost(), redisConfig.getPort(),
redisConfig.getTimeout()*1000, redisConfig.getPassword(), 0);
return jp;
}
}
redisservice
@Data
@Component
@ConfigurationProperties(prefix="redis")
public class RedisConfig {
private String host;
private int port;
private int timeout;//秒
private String password;
private int poolMaxTotal;
private int poolMaxIdle;
private int poolMaxWait;//秒
}
@Service
public class RedisService {
@Autowired
JedisPool jedisPool;
/**
* 获取当个对象
* */
public <T> T get(KeyPrefix prefix, String key, Class<T> clazz) {
Jedis jedis = null;
try {
jedis = jedisPool.getResource();
//生成真正的key
String realKey = prefix.getPrefix() + key;
String str = jedis.get(realKey);
T t = stringToBean(str, clazz);
return t;
}finally {
returnToPool(jedis);
}
}
/**
* 设置对象
* */
public <T> boolean set(KeyPrefix prefix, String key, T value) {
Jedis jedis = null;
try {
jedis = jedisPool.getResource();
String str = beanToString(value);
if(str == null || str.length() <= 0) {
return false;
}
//生成真正的key
String realKey = prefix.getPrefix() + key;
int seconds = prefix.expireSeconds();
if(seconds <= 0) {
jedis.set(realKey, str);
}else {
jedis.setex(realKey, seconds, str);
}
return true;
}finally {
returnToPool(jedis);
}
}
/**
* 判断key是否存在
* */
public <T> boolean exists(KeyPrefix prefix, String key) {
Jedis jedis = null;
try {
jedis = jedisPool.getResource();
//生成真正的key
String realKey = prefix.getPrefix() + key;
return jedis.exists(realKey);
}finally {
returnToPool(jedis);
}
}
/**
* 删除
* */
public boolean delete(KeyPrefix prefix, String key) {
Jedis jedis = null;
try {
jedis = jedisPool.getResource();
//生成真正的key
String realKey = prefix.getPrefix() + key;
long ret = jedis.del(realKey);
return ret > 0;
}finally {
returnToPool(jedis);
}
}
/**
* 增加值
* */
public <T> Long incr(KeyPrefix prefix, String key) {
Jedis jedis = null;
try {
jedis = jedisPool.getResource();
//生成真正的key
String realKey = prefix.getPrefix() + key;
return jedis.incr(realKey);
}finally {
returnToPool(jedis);
}
}
/**
* 减少值
* */
public <T> Long decr(KeyPrefix prefix, String key) {
Jedis jedis = null;
try {
jedis = jedisPool.getResource();
//生成真正的key
String realKey = prefix.getPrefix() + key;
return jedis.decr(realKey);
}finally {
returnToPool(jedis);
}
}
public boolean delete(KeyPrefix prefix) {
if(prefix == null) {
return false;
}
List<String> keys = scanKeys(prefix.getPrefix());
if(keys==null || keys.size() <= 0) {
return true;
}
Jedis jedis = null;
try {
jedis = jedisPool.getResource();
jedis.del(keys.toArray(new String[0]));
return true;
} catch (final Exception e) {
e.printStackTrace();
return false;
} finally {
if(jedis != null) {
jedis.close();
}
}
}
public List<String> scanKeys(String key) {
Jedis jedis = null;
try {
jedis = jedisPool.getResource();
List<String> keys = new ArrayList<String>();
String cursor = "0";
ScanParams sp = new ScanParams();
sp.match("*"+key+"*");
sp.count(100);
do{
ScanResult<String> ret = jedis.scan(cursor, sp);
List<String> result = ret.getResult();
if(result!=null && result.size() > 0){
keys.addAll(result);
}
//再处理cursor
cursor = ret.getStringCursor();
}while(!cursor.equals("0"));
return keys;
} finally {
if (jedis != null) {
jedis.close();
}
}
}
public static <T> String beanToString(T value) {
if(value == null) {
return null;
}
Class<?> clazz = value.getClass();
if(clazz == int.class || clazz == Integer.class) {
return ""+value;
}else if(clazz == String.class) {
return (String)value;
}else if(clazz == long.class || clazz == Long.class) {
return ""+value;
}else {
return JSON.toJSONString(value);
}
}
@SuppressWarnings("unchecked")
public static <T> T stringToBean(String str, Class<T> clazz) {
if(str == null || str.length() <= 0 || clazz == null) {
return null;
}
if(clazz == int.class || clazz == Integer.class) {
return (T)Integer.valueOf(str);
}else if(clazz == String.class) {
return (T)str;
}else if(clazz == long.class || clazz == Long.class) {
return (T)Long.valueOf(str);
}else {
return JSON.toJavaObject(JSON.parseObject(str), clazz);
}
}
private void returnToPool(Jedis jedis) {
if(jedis != null) {
jedis.close();
}
}
}
实体
消息实体：
@Data
public class MiaoshaMessage {
private MiaoshaUser user;
private long goodsId;
}
用户实体：
@Data
public class MiaoshaUser {
private Long id;
private String nickname;
private String password;
private String salt;
private String head;
private Date registerDate;
private Date lastLoginDate;
private Integer loginCount;
}
系统初始化
关于InitializingBean 接口的介绍：
由需要在BeanFactory设置所有属性后做出反应的 bean 实现的接口：例如，执行自定义初始化，或仅检查是否已设置所有必需属性。
实现InitializingBean的另一种方法是指定自定义 init 方法，例如在 XML bean 定义中。 有关所有 bean 生命周期方法的列表
在初始化方法中使用了一个本地HashMap
@Controller
@RequestMapping("/miaosha")
public class MiaoshaController implements InitializingBean {
@Autowired
MiaoshaUserService userService;
@Autowired
RedisService redisService;
@Autowired
GoodsService goodsService;
@Autowired
OrderService orderService;
@Autowired
MiaoshaService miaoshaService;
@Autowired
MQSender sender;
private HashMap<Long, Boolean> localOverMap = new HashMap<Long, Boolean>();
/**
* 系统初始化
* */
@Override
public void afterPropertiesSet() throws Exception {
List<GoodsVo> goodsList = goodsService.listGoodsVo();
if(goodsList == null) {
return;
}
for(GoodsVo goods : goodsList) {
redisService.set(GoodsKey.getMiaoshaGoodsStock, ""+goods.getId(), goods.getStockCount());
localOverMap.put(goods.getId(), false);
}
}//初始化时将库存全部加载到redis中
消息发送和接收者
@Service
public class MQSender {
private static Logger log = LoggerFactory.getLogger(MQSender.class);
@Autowired
AmqpTemplate amqpTemplate ;
public void sendMiaoshaMessage(MiaoshaMessage mm) {
String msg = RedisService.beanToString(mm);
log.info("send message:"+msg);
amqpTemplate.convertAndSend(MQConfig.MIAOSHA_QUEUE, msg);
}
@Service
public class MQReceiver {
private static Logger log = LoggerFactory.getLogger(MQReceiver.class);
@Autowired
RedisService redisService;
@Autowired
GoodsService goodsService;
@Autowired
OrderService orderService;
@Autowired
MiaoshaService miaoshaService;
@RabbitListener(queues=MQConfig.MIAOSHA_QUEUE)
public void receive(String message) {
log.info("receive message:"+message);
MiaoshaMessage mm = RedisService.stringToBean(message, MiaoshaMessage.class);
MiaoshaUser user = mm.getUser();
long goodsId = mm.getGoodsId();
GoodsVo goods = goodsService.getGoodsVoByGoodsId(goodsId);
int stock = goods.getStockCount();
if(stock <= 0) {
return;
}
//判断是否已经秒杀到了
MiaoshaOrder order = orderService.getMiaoshaOrderByUserIdGoodsId(user.getId(), goodsId);//从Redis中取订单
if(order != null)
{
return;//如果已经下过单，直接返回
}
//减库存 下订单 写入秒杀订单
miaoshaService.miaosha(user, goods);//写入到redis中
}
}
其中getMiaoshaOrderByUserIdGoodsId方法：
public MiaoshaOrder getMiaoshaOrderByUserIdGoodsId(long userId, long goodsId) {
//return orderDao.getMiaoshaOrderByUserIdGoodsId(userId, goodsId);
return redisService.get(OrderKey.getMiaoshaOrderByUidGid, ""+userId+"_"+goodsId, MiaoshaOrder.class);
}
方法 miaosha（(MiaoshaUser user, GoodsVo goods) ：
@Transactional
public OrderInfo miaosha(MiaoshaUser user, GoodsVo goods) {
//减库存 下订单 写入秒杀订单
boolean success = goodsService.reduceStock(goods);
if(success) {
//order_info maiosha_order
return orderService.createOrder(user, goods);
}else {
setGoodsOver(goods.getId());
return null;
}
}
controller
@RequestMapping(value="/do_miaosha", method=RequestMethod.POST)
@ResponseBody
public Result<Integer> miaosha(Model model,MiaoshaUser user,
@RequestParam("goodsId")long goodsId) {
model.addAttribute("user", user);//渲染前端的变量
if(user == null) {
return Result.error(CodeMsg.SESSION_ERROR);
}
//内存标记，减少redis访问
boolean over = localOverMap.get(goodsId);
if(over) {
return Result.error(CodeMsg.MIAO_SHA_OVER);
}
//预减库存
long stock = redisService.decr(GoodsKey.getMiaoshaGoodsStock, ""+goodsId);//从redis中获得库存量然后减库存，减少对数据库的访问
if(stock < 0) {
localOverMap.put(goodsId, true);
return Result.error(CodeMsg.MIAO_SHA_OVER);
}
//判断是否已经秒杀到了
MiaoshaOrder order = orderService.getMiaoshaOrderByUserIdGoodsId(user.getId(), goodsId);
if(order != null) {
return Result.error(CodeMsg.REPEATE_MIAOSHA);
}
//入队
MiaoshaMessage mm = new MiaoshaMessage();
mm.setUser(user);
mm.setGoodsId(goodsId);
sender.sendMiaoshaMessage(mm);//在这里进行 MiaoshaMessage消息的发送，消息进入队列中
return Result.success(0);//排队中
}
//用于重置的方法
@RequestMapping(value="/reset", method=RequestMethod.GET)
@ResponseBody
public Result<Boolean> reset() {
List<GoodsVo> goodsList = goodsService.listGoodsVo();
for(GoodsVo goods : goodsList) {
goods.setStockCount(10);
redisService.set(GoodsKey.getMiaoshaGoodsStock, ""+goods.getId(), 10);
localOverMap.put(goods.getId(), false);
}
redisService.delete(OrderKey.getMiaoshaOrderByUidGid);
redisService.delete(MiaoshaKey.isGoodsOver);
miaoshaService.reset(goodsList);
return Result.success(true);
}
//取得秒杀结果的接口
/**
* orderId：成功
* -1：秒杀失败
* 0： 排队中
* */
@RequestMapping(value="/result", method=RequestMethod.GET)
@ResponseBody
public Result<Long> miaoshaResult(Model model,MiaoshaUser user,
@RequestParam("goodsId")long goodsId) {
model.addAttribute("user", user);
if(user == null) {
return Result.error(CodeMsg.SESSION_ERROR);
}
long result =miaoshaService.getMiaoshaResult(user.getId(), goodsId);
return Result.success(result);//从redis中判断商品库存是否足够
}
}
//miaoshaService.getMiaoshaResult的方法
public long getMiaoshaResult(Long userId, long goodsId) {
MiaoshaOrder order = orderService.getMiaoshaOrderByUserIdGoodsId(userId, goodsId);
if(order != null) {
//秒杀成功
return order.getOrderId();
}else {
boolean isOver = getGoodsOver(goodsId);
if(isOver) {
return -1;
}else {
return 0;
}
}
}
private void setGoodsOver(Long goodsId) {
redisService.set(MiaoshaKey.isGoodsOver, ""+goodsId, true);
}
private boolean getGoodsOver(long goodsId) {
return redisService.exists(MiaoshaKey.isGoodsOver, ""+goodsId);
}
public void reset(List<GoodsVo> goodsList) {
goodsService.resetStock(goodsList);
orderService.deleteOrders();
}
//其中orderService的getMiaoshaOrderByUserIdGoodsId(long userId, long goodsId) 方法
public MiaoshaOrder getMiaoshaOrderByUserIdGoodsId(long userId, long goodsId) {
//return orderDao.getMiaoshaOrderByUserIdGoodsId(userId, goodsId);
return redisService.get(OrderKey.getMiaoshaOrderByUidGid, ""+userId+"_"+goodsId, MiaoshaOrder.class);
}//从相应的键中得到值并转化为MiaoshaOrder对象