RabbitMQ double ack 报错_channel.basicack(deliverytag, false)-优快云博客

报错信息：

16:50:10.134 ERROR 17788 ---  o.s.a.r.c.CachingConnectionFactory       : 
Channel shutdown: channel error; protocol method: #method<channel.close>(reply-code=406, reply-text=PRECONDITION_FAILED - unknown delivery tag 1, class-id=60, method-id=80)

使用rabbitmq的时候总是报错信道关闭。网上查了原因，大多说的是因为没有配置RabbitAdmin，无法自动创建exchange的。但是我配置了RabbitAdmin，也能够自动创建exchange，还是报这个错，而且这个错居然不影响消息队列运行。
后来看到这篇文章https://www.cnblogs.com/zhjh256/p/6434093.html，其中提到double ack问题，联想到我配置了序列化为json格式，所以重新配置了rabbitmq，

@Configuration
public class RabbitMqConfig {

    @Bean
    public RabbitAdmin rabbitTemplate(ConnectionFactory connectionFactory) {
        return new RabbitAdmin(connectionFactory);
    }

    @Bean
    public RabbitTemplate rabbitTemplate(ConnectionFactory connectionFactory, MessageConverter messageConverter) {
        RabbitTemplate template = new RabbitTemplate(connectionFactory);
        template.setMessageConverter(messageConverter);
        return template;
    }

    @Bean
    public SimpleRabbitListenerContainerFactory rabbitListenerContainerFactory(ConnectionFactory connectionFactory, MessageConverter messageConverter) {
        SimpleRabbitListenerContainerFactory factory = new SimpleRabbitListenerContainerFactory();
        factory.setConnectionFactory(connectionFactory);
        factory.setMessageConverter(messageConverter);
        return factory;
    }

    @Bean
    public MessageConverter messageConverter() {
        return new ContentTypeDelegatingMessageConverter(new Jackson2JsonMessageConverter());
    }
}

在yml配置文件中设置了手动ack


spring:
  rabbitmq:
    host: localhost
    port: 5672
    username: rabbit
    password: 123456
    virtual-host: /
    #生产端
    publisher-confirms: true
    publisher-returns: true
    template:
      mandatory: true
    #消费端
    listener:
      simple:
        acknowledge-mode: manual
        #初始连接数量
        concurrency: 5
        #最大连接数量
        max-concurrency: 10
        #限流
        prefetch: 1

yml中的签收模式失效，被注解注入的SimpleRabbitListenerContainerFactory覆盖，而它默认使用了自动签收。但是消费消息的时候又手动进行channel.basicAck(deliveryTag, false)，于是导致了两次ack,所以报错。
解决方法是在rabbitmq的factory中指定ack模式。

 public SimpleRabbitListenerContainerFactory rabbitListenerContainerFactory(ConnectionFactory connectionFactory, MessageConverter messageConverter) {
      SimpleRabbitListenerContainerFactory factory = new SimpleRabbitListenerContainerFactory();
      factory.setAcknowledgeMode(AcknowledgeMode.MANUAL);
      factory.setConnectionFactory(connectionFactory);
      factory.setMessageConverter(messageConverter);
      return factory;
  }
  ```