RabbitMQ-Java-08-备份交换机

• 跟发布确认高级差不多，也是为了解决防止消息丢失问题
• 无法投递的消息将转发给备份交换机

• 新建配置类
  • 新建一个普通交换机（direct），通过附加参数声明备份交换机

    return ExchangeBuilder.directExchange(EXCHANGE_NORMAL).withArgument(
        "alternate-exchange", EXCHANGE_BACKUP // 指定备份交换机
    ).build();
    

  • 新建一个普通队列
  • 绑定普通队列、交换机、路由key
  • 新建一个备份交换机（fanout）
  • 新建一个备份队列
  • 绑定备份队列、交换机
• 新建消费者组件
  • 正常队列消费者
  • 备份队列消费者
• 控制器
  • 生产者

spring.rabbitmq.host=192.168.3.202
spring.rabbitmq.port=5672
spring.rabbitmq.username=admin
spring.rabbitmq.password=123456
spring.rabbitmq.publisher-/confirm/i-type=correlated
spring.rabbitmq.publisher-returns=true

package cn.cnyasin.rabbit.config;

import org.springframework.amqp.core.*;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

@Configuration
public class MyBackupConfig {
    // 交换机
    public static final String EXCHANGE_NORMAL = "exchange_normal";
    public static final String EXCHANGE_BACKUP = "exchange_backup";

    // 队列
    public static final String QUEUE_NORMAL = "queue_normal";
    public static final String QUEUE_BACKUP = "queue_backup";

    // 路由key
    public static final String ROUTING_NORMAL = "routing_normal";

    // 声明交换机
    @Bean
    public DirectExchange exchangeNormal() {
        return ExchangeBuilder.directExchange(EXCHANGE_NORMAL).withArgument(
                "alternate-exchange", EXCHANGE_BACKUP // 指定备份交换机
        ).build();
    }

    @Bean
    public FanoutExchange exchangeBackup() {
        return new FanoutExchange(EXCHANGE_BACKUP);
    }

    // 声明队列
    @Bean
    public Queue queueNormal() {
        return QueueBuilder.durable(QUEUE_NORMAL).build();
    }

    @Bean
    public Queue queueBackup() {
        return QueueBuilder.durable(QUEUE_BACKUP).build();
    }

    // 绑定队列、交换机、路由key
    @Bean
    public Binding queueNormalBindExchangeNormal(
            @Qualifier("queueNormal") Queue queue,
            @Qualifier("exchangeNormal") Exchange exchange
    ) {
        return BindingBuilder.bind(queue).to(exchange).with(ROUTING_NORMAL).noargs();
    }

    @Bean
    public Binding queueBackupBindExchangeBackup(
            @Qualifier("queueBackup") Queue queue,
            @Qualifier("exchangeBackup") Exchange exchange
    ) {
        return BindingBuilder.bind(queue).to(exchange).with("").noargs();
    }

}

package cn.cnyasin.rabbit.consumer;

import cn.cnyasin.rabbit.config.MyBackupConfig;
import lombok.extern.slf4j.Slf4j;
import org.springframework.amqp.rabbit.annotation.RabbitListener;
import org.springframework.stereotype.Component;

import java.util.Date;

@Slf4j
@Component
public class MyBackupConsumer {
    
    @RabbitListener(queues = MyBackupConfig.QUEUE_NORMAL)
    public void queueNormalConsumer(String message) {
        log.info("[*] [{}] 正常队列收到消息：{}", new Date().toString(), message);
    }

    
    @RabbitListener(queues = MyBackupConfig.QUEUE_BACKUP)
    public void queueBackupConsumer(String message) {
        log.info("[*] [{}] 备份队列收到消息：{}", new Date().toString(), message);
    }

}

package cn.cnyasin.rabbit.controller;

import cn.cnyasin.rabbit.config.MyBackupConfig;
import lombok.extern.slf4j.Slf4j;
import org.springframework.amqp.rabbit.core.RabbitTemplate;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import java.util.Date;

@Slf4j
@RestController
@RequestMapping("/backup")
public class MyBackupController {

    @Autowired
    private RabbitTemplate rabbitTemplate;

    
    @RequestMapping("/send/{msg}")
    public String send(@PathVariable String msg) {
        log.info("[*] [{}] 准备发送消息：{}", new Date().toString(), msg);

        // 发送到存在的路由key
        rabbitTemplate.convertAndSend(MyBackupConfig.EXCHANGE_NORMAL, MyBackupConfig.ROUTING_NORMAL, msg);
        // 发送到不存在的路由key
        rabbitTemplate.convertAndSend(MyBackupConfig.EXCHANGE_NORMAL, "qwe", msg);

        return "ok";
    }

}