1.为什么会用到延时队列?
场景: 最近在开发一款系统中遇到这样一个场景,A系统开通套餐需要把套餐信息以邮件的形式发送给相关工作人员,经过人工审核通过后,在B系统里面开通,A系统会调B系统套餐列表接口查询套餐是否开通成功,开通成功则从A系统去完成订单,假如超过设定时间未开通成功,则关闭订单并退费.
(这东西俗称"套娃")
这时候用RabbitMQ的延时队列就可以完美的解决这个问题
2.为什么会提到多策略?
场景: 假如A系统还有别的功能添加需要经过人工审核之后在B系统中添加成功之后,A系统才会显示添加成功,但是又不想写很多队列啊消费者等代码.就可以用到这种策略模式,换句话说 就是类似 if… else …能明白了吧.
3.进入今天主题
整体流程图:
生产者生产一条延时消息，根据需要延时时间的不同，利用routingkey将消息路由到延时队列，队列都设置了TTL属性，并绑定到死信交换机中，消息过期后，根据routingkey又会被路由到死信队列中，消费者只需要监听死信队列,拿到消息去具体的策略实现类进行后续业务处理即可。
有了这个图写代码就简单了.
mq配置类 声明队列,路由键,交换机之间的关系;以及生产者消费者 rabbitmq等Bean
RabbitMqConfig
注意 监听我也写在配置类里面SimpleMessageListenerContainer用的这个类去设置的队列
simpleMessageListenerContainer.setQueueNames(DEAD_LETTER_QUEUE_NAME);
package com.king.alice.rabbitmq.config;
import com.king.alice.rabbitmq.delay.consumer.MessageConsumer;
import com.king.alice.rabbitmq.delay.consumer.Strategy;
import com.king.alice.rabbitmq.delay.provider.MessageProvider;
import org.springframework.amqp.core.*;
import org.springframework.amqp.rabbit.connection.ConnectionFactory;
import org.springframework.amqp.rabbit.core.RabbitTemplate;
import org.springframework.amqp.rabbit.listener.SimpleMessageListenerContainer;
import org.springframework.amqp.support.converter.Jackson2JsonMessageConverter;
import org.springframework.beans.factory.ObjectProvider;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
/**
* @Author wlt
* @Description rabbitmq配置类
* @Date 2022/9/4
* @Param
* @return
**/
@Configuration
public class RabbitMqConfig {
public static final String DELAY_EXCHANGE_NAME = "delay.alice.exchange";
public static final String DELAY_QUEUE_NAME = "delay.alice.queue";
public static final String DELAY_QUEUE_ROUTING_KEY = "delay.alice.queue.routing.key";
public static final String DEAD_LETTER_EXCHANGE = "ttl.alice.exchange";
public static final String DEAD_LETTER_QUEUE_ROUTING_KEY = "ttl.alice.queue.routing.key";
public static final String DEAD_LETTER_QUEUE_NAME = "ttl.alice.queue";
/**
* 声明延时Exchange
* @return
*/
@Bean("delayExchange")
public DirectExchange delayExchange(){
return new DirectExchange(DELAY_EXCHANGE_NAME);
}
/**
* 功能描述: <br>
* <声明死信Exchange>
*/
@Bean("deadLetterExchange")
public DirectExchange deadLetterExchange(){
return new DirectExchange(DEAD_LETTER_EXCHANGE);
}
/**
* 声明延时队列 并绑定到对应的死信交换机
* @return
*/
@Bean("delayQueue")
public Queue delayQueue(){
Map<String, Object> args = new HashMap<>(2);
// x-dead-letter-exchange 这里声明当前队列绑定的死信交换机
args.put("x-dead-letter-exchange", DEAD_LETTER_EXCHANGE);
// x-dead-letter-routing-key 这里声明当前队列的死信路由key
args.put("x-dead-letter-routing-key", DEAD_LETTER_QUEUE_ROUTING_KEY);
// x-message-ttl 声明队列的TTL
// args.put("x-message-ttl", 6000);
return QueueBuilder.durable(DELAY_QUEUE_NAME).withArguments(args).build();
}
/**
* 功能描述: <br>
* <声明死信队列用于接收延时处理的消息>
*/
@Bean("deadLetterQueue")
public Queue deadLetterQueue(){
return new Queue(DEAD_LETTER_QUEUE_NAME);
}
/**
* 功能描述: <br>
* <声明延时队列绑定关系>
* @Param:
* @Return:
* @Author: 大魔王
* @Date: 2023/8/15 20:00
*/
@Bean
public Binding delayBinding(@Qualifier("delayQueue") Queue queue,
@Qualifier("delayExchange") DirectExchange exchange){
return BindingBuilder.bind(queue).to(exchange).with(DELAY_QUEUE_ROUTING_KEY);
}
/**
* 功能描述: <br>
* <声明死信队列A绑定关系>
* @Param:
* @Return:
* @Author: 大魔王
* @Date: 2023/8/15 20:01
*/
@Bean
public Binding deadLetterBinding(@Qualifier("deadLetterQueue") Queue queue,
@Qualifier("deadLetterExchange") DirectExchange exchange){
return BindingBuilder.bind(queue).to(exchange).with(DEAD_LETTER_QUEUE_ROUTING_KEY);
}
@Bean
@ConditionalOnMissingBean
public MessageProvider messageProvider(@Qualifier("delayRabbitTemplate") RabbitTemplate template) {
return new MessageProvider(template);
}
@Bean
@ConditionalOnMissingBean
public MessageConsumer messageConsumer(ObjectProvider<List<Strategy>> provider) {
return new MessageConsumer(provider);
}
@Bean
@ConditionalOnMissingBean
public RabbitTemplate delayRabbitTemplate(ConnectionFactory connectionFactory) {
RabbitTemplate template = new RabbitTemplate(connectionFactory);
template.setMessageConverter(new Jackson2JsonMessageConverter());
return template;
}
@Bean
SimpleMessageListenerContainer simpleMessageListenerContainer(MessageConsumer messageConsumer, ConnectionFactory factory) {
SimpleMessageListenerContainer simpleMessageListenerContainer = new SimpleMessageListenerContainer(factory);
simpleMessageListenerContainer.setQueueNames(DEAD_LETTER_QUEUE_NAME);
simpleMessageListenerContainer.setExposeListenerChannel(true);
simpleMessageListenerContainer.setMessageListener(messageConsumer);
return simpleMessageListenerContainer;
}
public static final String EXCHANGE_NAME = "alice_topic_exchange";
public static final String QUEUE_NAME = "alice_queue";
@Bean("aliceExchange")
public Exchange aliceExchange() {
return ExchangeBuilder.topicExchange(EXCHANGE_NAME).durable(true).build();
}
@Bean("aliceQueue")
public Queue aliceQueue() {
return QueueBuilder.durable(QUEUE_NAME).build();
}
@Bean
public Binding bindQueueExchange(@Qualifier("aliceQueue") Queue queue, @Qualifier("aliceExchange") Exchange exchange) {
return BindingBuilder.bind(queue).to(exchange).with("alice.#").noargs();
}
}
生产者:
MessageProvider
package com.king.alice.rabbitmq.delay.provider;
import cn.hutool.core.date.DateUtil;
import com.king.alice.common.json.JSON;
import com.king.alice.rabbitmq.config.RabbitMqConfig;
import com.king.alice.rabbitmq.delay.bean.DelayMessage;
import lombok.extern.slf4j.Slf4j;
import org.junit.Assert;
import org.springframework.amqp.rabbit.core.RabbitTemplate;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;
import java.util.Date;
/**
* @author 大魔王
*/
@Slf4j
@Component
public class MessageProvider {
@Autowired
private final RabbitTemplate rabbitTemplate;
public MessageProvider(RabbitTemplate rabbitTemplate) {
this.rabbitTemplate = rabbitTemplate;
}
/**
* send delay message
*/
public void sendMessage(DelayMessage delayMessage) {
Assert.assertNotNull(delayMessage);
log.info(" now date {},delay {} seconds to write to the message queue", DateUtil.format(new Date(), "yyyy-MM-dd HH:mm:ss"), delayMessage.getDelay());
rabbitTemplate.convertAndSend(RabbitMqConfig.DELAY_EXCHANGE_NAME, RabbitMqConfig.DELAY_QUEUE_ROUTING_KEY, delayMessage,
message -> {
message.getMessageProperties().setExpiration(String.valueOf(delayMessage.getDelay() * 1000));
return message;
});
}
}
消费者:
package com.king.alice.rabbitmq.delay.consumer;
import cn.hutool.core.util.ObjectUtil;
import com.king.alice.common.json.JSONObject;
import com.king.alice.rabbitmq.delay.bean.AliceMessage;
import com.king.alice.rabbitmq.delay.bean.DelayMessage;
import lombok.extern.slf4j.Slf4j;
import org.springframework.amqp.core.AcknowledgeMode;
import org.springframework.amqp.core.Message;
import org.springframework.amqp.core.MessageListener;
import org.springframework.amqp.support.converter.Jackson2JsonMessageConverter;
import org.springframework.amqp.support.converter.MessageConverter;
import org.springframework.beans.factory.ObjectProvider;
import org.springframework.stereotype.Component;
import org.springframework.util.CollectionUtils;
import java.lang.reflect.ParameterizedType;
import java.lang.reflect.Type;
import java.util.List;
import java.util.Map;
import java.util.Optional;
import java.util.concurrent.ConcurrentHashMap;
import java.util.stream.Collectors;
/**
* @author 大魔王
*/
@Slf4j
public class MessageConsumer implements MessageListener {
private final Map<Type, List<Strategy>> strategyMap = new ConcurrentHashMap<>();
public MessageConsumer(ObjectProvider<List<Strategy>> stategyProvider) {
List<Strategy> handleList = stategyProvider.getIfAvailable();
Optional<? extends List<Strategy>> optionalStrategies = Optional.ofNullable(handleList);
optionalStrategies.ifPresent(strategies -> strategies.stream().filter(strategy -> {
Type genericInterface = strategy.getClass().getGenericInterfaces()[0];
return genericInterface instanceof ParameterizedType;
}).map(strategy -> ((ParameterizedType) strategy.getClass().getGenericInterfaces()[0]).getActualTypeArguments()[0])
.collect(Collectors.toSet()).forEach(delayMessages -> {
List<Strategy> collect = strategies.stream().filter(strategy -> {
Type genericInterface = strategy.getClass().getGenericInterfaces()[0];
if (genericInterface instanceof ParameterizedType) {
Type actualTypeArgument = ((ParameterizedType) genericInterface).getActualTypeArguments()[0];
return delayMessages.getTypeName().equals(actualTypeArgument.getTypeName());
}
return false;
}).collect(Collectors.toList());
strategyMap.put(delayMessages, collect);
}));
}
@Override
public void onMessage(Message message) {
MessageConverter messageConverter = new Jackson2JsonMessageConverter();
DelayMessage delayMessage = (DelayMessage) messageConverter.fromMessage(message);
List<Strategy> strategyList = strategyMap.get(delayMessage.getClass());
if (!CollectionUtils.isEmpty(strategyList)) {
strategyList.forEach(strategy -> strategy.handle(delayMessage));
} else {
log.info("Missing message processing class");
}
}
}
策略相关Bean,接口以及实现类
DelayMessage
package com.king.alice.rabbitmq.delay.bean;
/**
* @author 大魔王
*/
public interface DelayMessage{
/**
* 获得延迟时间（单位秒）
*
* @return 延迟时间单位秒
*/
int getDelay();
}
AliceMessage
package com.king.alice.rabbitmq.delay.bean;
import lombok.Getter;
import lombok.Setter;
/**
* @author 大魔王
*/
@Getter
@Setter
public class AliceMessage implements DelayMessage {
/**
* 用户邮箱
*/
String email;
/**
* 订单类型
*/
String orderType;
/**
* 执行次数
*/
Integer dealCount;
/**
* 延时秒数
*/
int delay;
@Override
public int getDelay() {
return this.delay;
}
public void setDelay(int delay) {
this.delay = delay;
}
}
UserMessage
package com.king.alice.rabbitmq.delay.bean;
import lombok.Getter;
import lombok.Setter;
/**
* @author 大魔王
*/
@Getter
@Setter
public class UserMessage implements DelayMessage{
/**
* 用户
*/
String username;
/**
* token
*/
String token;
/**
* 执行次数
*/
Integer dealCount;
/**
* 延时秒数
*/
int delay;
@Override
public int getDelay() {
return this.delay;
}
public void setDelay(int delay) {
this.delay = delay;
}
}
Strategy
package com.king.alice.rabbitmq.delay.consumer;
import com.king.alice.rabbitmq.delay.bean.DelayMessage;
/**
* @author 大魔王
*/
public interface Strategy<T extends DelayMessage> {
/**
* 处理消息的方法
*
* @param delayMessage 收到的消息
*/
void handle(T delayMessage);
}
AliceMessageHandler
package com.king.alice.rabbitmq;
import com.king.alice.common.json.JSON;
import com.king.alice.common.json.JSONObject;
import com.king.alice.rabbitmq.delay.bean.AliceMessage;
import com.king.alice.rabbitmq.delay.consumer.Strategy;
import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Component;
/**
* @author 大魔王
*/
@Component
@Slf4j
public class AliceMessageHandler implements Strategy<AliceMessage> {
@Override
public void handle(AliceMessage delayMessage) {
log.info("AliceMessage响应体{}", JSONObject.parseObject(JSON.toJSONString(delayMessage)));
}
}
UserMessageHandler
package com.king.alice.rabbitmq;
import com.king.alice.common.json.JSON;
import com.king.alice.common.json.JSONObject;
import com.king.alice.rabbitmq.delay.bean.UserMessage;
import com.king.alice.rabbitmq.delay.consumer.Strategy;
import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Component;
/**
* @author 大魔王
*/
@Slf4j
@Component
public class UserMessageHandler implements Strategy<UserMessage> {
@Override
public void handle(UserMessage delayMessage) {
log.info("UserMessage响应体{}", JSONObject.parseObject(JSON.toJSONString(delayMessage)));
}
}
接下来 我们写个controller测试一下
SysAccountController
package com.king.alice.manage.sys.controller;
import cn.hutool.core.date.DateUtil;
import com.king.alice.manage.sys.entity.SysAccount;
import com.king.alice.manage.sys.service.SysAccountService;
import com.king.alice.rabbitmq.delay.bean.AliceMessage;
import com.king.alice.rabbitmq.delay.bean.UserMessage;
import com.king.alice.rabbitmq.delay.provider.MessageProvider;
import lombok.extern.slf4j.Slf4j;
import org.springframework.amqp.rabbit.core.RabbitTemplate;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.domain.Page;
import org.springframework.data.domain.PageRequest;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.*;
import javax.annotation.Resource;
import java.util.Date;
/**
* 账号表(SysAccount)表控制层
*
* @author makejava
* @since 2023-08-09 11:40:16
*/
@RestController
@Slf4j
public class SysAccountController {
/**
* 服务对象
*/
@Resource
private SysAccountService sysAccountService;
@Autowired
private MessageProvider messageProvider;
@PostMapping("/send-alice-message")
public String sendMsg(@RequestBody AliceMessage aliceMessage) {
messageProvider.sendMessage(aliceMessage);
log.info("当前时间：{},收到aliceMessage请求，msg:{}", DateUtil.format(new Date(), "yyyy-MM-dd HH:mm:ss"), aliceMessage);
return "success";
}
@PostMapping("/send-user-message")
public String sendMsg(@RequestBody UserMessage userMessage) {
messageProvider.sendMessage(userMessage);
log.info("当前时间：{},收到userMessage请求，msg:{}", DateUtil.format(new Date(), "yyyy-MM-dd HH:mm:ss"), userMessage);
return "success";
}
}
调接口
第一个策略:
控制台打印
第二个策略:
延时12秒成功接收到消息
