利用延迟消息,解决用户下单后未支付,需要取消订单的业务流程
目前网上关于使用RabbitMQ实现延迟消息的文章,大多都是讲如何利用RabbitMQ的死信队列来实现,实现方案看起来都很繁琐复杂,并且还是使用原始的RabbitMQ Client API来实现的,更加显得啰嗦。更多springboot整合实战内容,可以在公众号持续关注springboot相关内容。
Spring Boot 已经对RabbitMQ Client API进行了包装,使用起来简洁很多,下面详细介绍一下如何利用rabbitmq_delayed_message_exchange
插件和Spring Boot来实现延迟消息。
软件准备
erlang
请参考Win10下安装erlang
https://blog.csdn.net/linsongbin1/article/details/80170487
本文使用的版本是:
-
Erlang 20.3
RabbitMQ
请参考win10下安装rabbitmq
https://blog.csdn.net/linsongbin1/article/details/80170567
本文使用的是window版本的RabbitMQ,版本号是:
-
3.7.4
rabbitmq_delayed_message_exchange插件
插件下载地址:
http://www.rabbitmq.com/community-plugins.html
集成RabbitMQ
这个就非常简单了,直接在maven工程的pom.xml文件中加入
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-amqp</artifactId>
</dependency>
Spring Boot的版本我使用的是2.0.1.RELEASE.
接下来在application.properties文件中加入redis配置:
spring.rabbitmq.host=127.0.0.1
spring.rabbitmq.port=5672
spring.rabbitmq.username=guest
spring.rabbitmq.password=guest
定义ConnectionFactory和RabbitTemplate
也很简单,代码如下:
package com.mq.rabbitmq;
import org.springframework.amqp.rabbit.connection.CachingConnectionFactory;
import org.springframework.amqp.rabbit.connection.ConnectionFactory;
import org.springframework.amqp.rabbit.core.RabbitTemplate;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
@Configuration
@ConfigurationProperties(prefix = "spring.rabbitmq")
public class RabbitMqConfig {
private String host;
private int port;
private String userName;
private String password;
@Bean
public ConnectionFactory connectionFactory() {
CachingConnectionFactory cachingConnectionFactory = new CachingConnectionFactory(host,port);
cachingConnectionFactory.setUsername(userName);
cachingConnectionFactory.setPassword(password);
cachingConnectionFactory.setVirtualHost("/");
cachingConnectionFactory.setPublisherConfirms(true);
return cachingConnectionFactory;
}
@Bean
public RabbitTemplate rabbitTemplate() {
RabbitTemplate rabbitTemplate = new RabbitTemplate(connectionFactory());
return rabbitTemplate;
}
public String getHost() {
return host;
}
public void setHost(String host) {
this.host = host;
}
public int getPort() {
return port;
}
public void setPort(int port) {
this.port = port;
}
public String getUserName() {
return userName;
}
public void setUserName(String userName) {
this.userName = userName;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
}
Exchange和Queue配置
package com.mq.rabbitmq;
import org.springframework.amqp.core.*;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import java.util.HashMap;
import java.util.Map;
@Configuration
public class QueueConfig {
@Bean
public CustomExchange delayExchange() {
Map<String, Object> args = new HashMap<>();
args.put("x-delayed-type", "direct");
return new CustomExchange("test_exchange", "x-delayed-message",true, false,args);
}
@Bean
public Queue queue() {
Queue queue = new Queue("test_queue_1", true);
return queue;
}
@Bean
public Binding binding() {
return BindingBuilder.bind(queue()).to(delayExchange()).with("test_queue_1").noargs();
}
}
这里要特别注意的是,使用的是CustomExchange,不是DirectExchange,另外CustomExchange的类型必须是x-delayed-message。
实现消息发送
package com.mq.rabbitmq;
import org.springframework.amqp.AmqpException;
import org.springframework.amqp.core.Message;
import org.springframework.amqp.core.MessagePostProcessor;
import org.springframework.amqp.rabbit.core.RabbitTemplate;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import java.text.SimpleDateFormat;
import java.util.Date;
@Service
public class MessageServiceImpl {
@Autowired
private RabbitTemplate rabbitTemplate;
public void sendMsg(String queueName,String msg) {
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
System.out.println("消息发送时间:"+sdf.format(new Date()));
rabbitTemplate.convertAndSend("test_exchange", queueName, msg, new MessagePostProcessor() {
@Override
public Message postProcessMessage(Message message) throws AmqpException {
message.getMessageProperties().setHeader("x-delay",3000);
return message;
}
});
}
}
注意在发送的时候,必须加上一个header
-
x-delay
在这里我设置的延迟时间是3秒。
消息消费者
package com.mq.rabbitmq;
import org.springframework.amqp.rabbit.annotation.RabbitHandler;
import org.springframework.amqp.rabbit.annotation.RabbitListener;
import org.springframework.stereotype.Component;
import java.text.SimpleDateFormat;
import java.util.Date;
@Component
public class MessageReceiver {
@RabbitListener(queues = "test_queue_1")
public void receive(String msg) {
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
System.out.println("消息接收时间:"+sdf.format(new Date()));
System.out.println("接收到的消息:"+msg);
}
}
运行Spring Boot程序和发送消息
直接在main方法里运行Spring Boot程序,Spring Boot会自动解析MessageReceiver类的。
接下来只需要用Junit运行一下发送消息的接口即可。
package com.mq.rabbitmq;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;
@RunWith(SpringRunner.class)
@SpringBootTest
public class RabbitmqApplicationTests {
@Autowired
private MessageServiceImpl messageService;
@Test
public void send() {
messageService.sendMsg("test_queue_1","hello i am delay msg,happy 61");
}
}
运行完后,可以看到如下信息:
消息发送时间:2020-06-01 8:44:53
3秒钟后,Spring Boot控制台会输出:
消息接收时间:2020-06-01 8::44:56
接收到的消息:hello i am delay msg,happy 61
注:文章代码可以引用,出错不要恨我,嘿嘿!!!