公司网站建设模板免费,一个完整的网站 技术,成都装修设计公司排名,引擎seo优2019独角兽企业重金招聘Python工程师标准 通过Publisher Confirms and Returns机制#xff0c;生产者可以判断消息是否发送到了exchange及queue#xff0c;而通过消费者确认机制#xff0c;Rabbitmq可以决定是否重发消息给消费者#xff0c;以保证消息被处理… 2019独角兽企业重金招聘Python工程师标准 通过Publisher Confirms and Returns机制生产者可以判断消息是否发送到了exchange及queue而通过消费者确认机制Rabbitmq可以决定是否重发消息给消费者以保证消息被处理。 1.什么是Publisher Confirms and Returns Delivery processing acknowledgements from consumers to RabbitMQ are known as acknowledgements in AMQP 0-9-1 parlance; broker acknowledgements to publishers are a protocol extension called publisher confirms. 地址http://www.rabbitmq.com/confirms.html 根据RabbitMq官网定义rabbitmq代理(broker)对发布者(publishers)的确认被称作发布者确认(publisher confirms)这种机制是Rabbitmq对标准Amqp协议的扩展。因此通过这种机制可以确认消息是否发送给了目标。 2.如何通过Spring amqp来使用Publisher Confirms and Returns机制 Confirmed and returned messages are supported by setting the CachingConnectionFactory’s publisherConfirms and publisherReturns properties to ‘true’ respectively.When these options are set, Channel s created by the factory are wrapped in an PublisherCallbackChannel, which is used to facilitate the callbacks. When such a channel is obtained, the client can register a PublisherCallbackChannel.Listener with the Channel. The PublisherCallbackChannel implementation contains logic to route a confirm/return to the appropriate listener. These features are explained further in the following sections. http://docs.spring.io/spring-amqp/docs/1.6.3.RELEASE/reference/html/_reference.html#cf-pub-conf-ret 通过Spring amqp文档可以看到要使用这种机制需要将Template模版的设publisherConfirms 或publisherReturns 属性设置为true此外ConnectionFactory要配置为CachingConnectionFactory。 bean idconnectionFactoryclassorg.springframework.amqp.rabbit.connection.CachingConnectionFactoryproperty namehost value192.168.2.133 /property nameport value5672 /property nameusername valuesun /property namepassword value123456 /property namepublisherConfirms valuetrue /property namepublisherReturns valuetrue //bean 2.1 ConfirmCallback的使用及触发的一种场景 import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.amqp.rabbit.core.RabbitTemplate;
import org.springframework.amqp.rabbit.support.CorrelationData;
import org.springframework.stereotype.Service;/*** author wangzhongqiu* Created on 2017/10/31.* description:继承RabbitTemplate.ConfirmCallback,消息确认监听器*/
Service
public class ConfirmCallBackListener implements RabbitTemplate.ConfirmCallback {private Logger log LoggerFactory.getLogger(CommonProducer.class);Overridepublic void confirm(CorrelationData correlationData, boolean ack, String cause) {log.info(收到回调成功发送到broker);}
} 2.2 ReturnCallback的使用及触发的一种场景 import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.amqp.core.Message;
import org.springframework.amqp.rabbit.core.RabbitTemplate;
import org.springframework.stereotype.Service;/*** author wangzhongqiu* Created on 2017/10/31.* description:继承RabbitTemplate.ReturnCallback,消息发送失败返回监听器*/
Service
public class ReturnCallBackListener implements RabbitTemplate.ReturnCallback {private Logger log LoggerFactory.getLogger(CommonProducer.class);Overridepublic void returnedMessage(Message message, int replyCode, String replyText, String exchange, String routingKey) {log.info(收到回调);log.info(return--message: new String(message.getBody()) ,replyCode: replyCode ,replyText: replyText ,exchange: exchange ,routingKey: routingKey);}
} 使用场景 如果消息没有到exchange,则confirm回调,ackfalse 如果消息到达exchange,则confirm回调,acktrue exchange到queue成功,则不回调return exchange到queue失败,则回调return(需设置mandatorytrue,否则不回回调,消息就丢了) 转载于:https://my.oschina.net/xiaominmin/blog/1811701
