场景
用户下单后,如果30min未支付,则删除该订单,这时候就要可以用延迟队列
准备
利用rabbitmq_delayed_message_exchange插件;
首先下载该插件:https://www.rabbitmq.com/community-plugins.html
然后把该插件放到rabbitmq安装目录plugins下;
进入到sbin目录下,执行"rabbitmq-plugins.bat enable rabbitmq_delayed_message_exchange";
关闭RabbitMQ服务,然后再启动(直接重启该插件可能会不生效)。
SpringBoot RabbitMQ代码
application.properties配置文件
spring.application.name=spring-boot-rabbitmq
spring.rabbitmq.host=localhost
spring.rabbitmq.port=5672
spring.rabbitmq.username=nut
spring.rabbitmq.password=nut
配置类
注意这里的"x-delayed-type"和"x-delayed-message"
/**
* 延迟队列配置exchange
*/
@Configuration
public class DelayQueueConfig { public static final String DELAY_EXCHANGE = "DELAY_EXCHANGE";
public static final String DELAY_QUEUE = "DELAY_QUEUE";
public static final String DELAY_ROUTING_KEY = "DELAY_ROUTING_KEY"; @Bean("delayExchange")
public Exchange delayExchange() {
Map<String, Object> args = new HashMap<>(1);
// x-delayed-type 声明 延迟队列Exchange的类型
args.put("x-delayed-type", "direct");
return new CustomExchange(DELAY_EXCHANGE, "x-delayed-message",true, false,args);
} @Bean("delayQueue")
public Queue delayQueue() {
return QueueBuilder.durable(DELAY_QUEUE).build();
} /**
* 将延迟队列通过routingKey绑定到延迟交换器
*
* @return
*/
@Bean
public Binding delayQueueBindExchange() {
return new Binding(DELAY_QUEUE, Binding.DestinationType.QUEUE, DELAY_EXCHANGE, DELAY_ROUTING_KEY, null);
} }
生产者
发送消息时,指定延迟的毫秒
/**
* 延迟队列发送者
*/
@Component
@Slf4j
public class DelayQueueSender { @Autowired
private RabbitTemplate rabbitTemplate; public void sendDelayQueue(int number) {
log.warn("延迟队列发送 : {} milliseconds", number);
// 这里的Exchange可以是业务的Exchange,为了方便测试这里直接往死信Exchange里投递消息
rabbitTemplate.convertAndSend(
DelayQueueConfig.DELAY_EXCHANGE,
DelayQueueConfig.DELAY_ROUTING_KEY,
number, (message) -> {
// 设置延迟的毫秒数
message.getMessageProperties().setDelay(number);
log.info("Now : {}", ZonedDateTime.now());
return message;
});
}
}
消费者
/**
* 延迟队列消费者
*/
@Component
@Slf4j
@RabbitListener(queues = DelayQueueConfig.DELAY_QUEUE)
public class DelayQueueConsumer { @RabbitHandler
public void receiveDelayMessage(Integer milliseconds){
log.warn("DelayQueueConsumer Time : {}, and the millis : {}", ZonedDateTime.now(), milliseconds); } }
测试
先启动项目;
然后在测试类中发送消息;
@RunWith(SpringRunner.class)
@SpringBootTest
public class RabbitmqApplicationTests { @Autowired
private DelayQueueSender delayQueueSender; @Test
public void testDelayQueueSender(){
delayQueueSender.sendDelayQueue(5000);
}
}
发送消息窗口:
消费者受到消息:
时间间隔证明延迟队列发送完成!
参考:
https://blog.csdn.net/linsongbin1/article/details/80178122
https://blog.csdn.net/youjin/article/details/82586888
https://docs.spring.io/spring-amqp/docs/2.0.0.M2/reference/htmlsingle/#delayed-message-exchange
https://www.rabbitmq.com/blog/2015/04/16/scheduling-messages-with-rabbitmq/