rabbitMQ解决消息丢失-消费者手工确认ack

素颜马尾好姑娘i 2022-10-13 01:48 208阅读 0赞

maven配置

<?xml version="1.0" encoding="UTF-8"?>
    <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
             xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
        <modelVersion>4.0.0</modelVersion>
        <parent>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-parent</artifactId>
            <version>2.5.0</version>
            <relativePath/> 
        </parent>
        <groupId>com.example</groupId>
        <artifactId>SpringbootTest</artifactId>
        <version>0.0.1-SNAPSHOT</version>
        <name>SpringbootTest</name>
        <description>Demo project for Spring Boot</description>
        <properties>
            <java.version>1.8</java.version>
        </properties>
        <dependencies>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter</artifactId>
            </dependency>
            <dependency>
                <groupId>com.rabbitmq</groupId>
                <artifactId>amqp-client</artifactId>
                <version>5.10.0</version>
            </dependency>
    
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-devtools</artifactId>
                <scope>runtime</scope>
                <optional>true</optional>
            </dependency>
            <dependency>
                <groupId>org.projectlombok</groupId>
                <artifactId>lombok</artifactId>
                <optional>true</optional>
            </dependency>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-test</artifactId>
                <scope>test</scope>
            </dependency>
        </dependencies>
    
        <build>
            <plugins>
                <plugin>
                    <groupId>org.springframework.boot</groupId>
                    <artifactId>spring-boot-maven-plugin</artifactId>
                    <configuration>
                        <excludes>
                            <exclude>
                                <groupId>org.projectlombok</groupId>
                                <artifactId>lombok</artifactId>
                            </exclude>
                        </excludes>
                    </configuration>
                </plugin>
            </plugins>
        </build>
    
    </project>

工具类

import com.rabbitmq.client.Channel;
    import com.rabbitmq.client.Connection;
    import com.rabbitmq.client.ConnectionFactory;
    
    public class MqChanneUtils {
        public static Channel getChannel() throws Exception{
            ConnectionFactory factory = new ConnectionFactory();
            factory.setHost("127.0.0.1");
            factory.setPort(5672);
            factory.setUsername("guest");
            factory.setPassword("guest");
            factory.setVirtualHost("/");
            factory.setConnectionTimeout(20000);
            Connection connection = factory.newConnection();
            Channel channel = connection.createChannel();
            return channel;
        }
    }

public class SleepUtils {
    
        public static void sleeper(int i){
            try {
                Thread.sleep(i*1000);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
    }

生产者

public class MessProductor {
        public static void main(String[] args) throws Exception{
            Channel channel = MqChanneUtils.getChannel();
    
            for(int i = 0; i < 10; i++){
                System.out.println("生产消息:" + i);
                String msg = "Hello RabbitMQ" + i;
                channel.basicPublish("", "test01", null, msg.getBytes());
            }
            //5.记得关闭相关的连接
            channel.close();
    
        }
    }

创建消费者01和02。代码逻辑都是一样的。只不过一个睡眠30s，一个睡眠2秒。这样做为了更好的看到应答效果。在一个消息没应答之前，是无法继续消费消息的。当一个消费者出现问题，比如我停掉01消费者。这时候消费会被02去消费。这样就保证了消息是在被消费后才能从生产者移除。

public class ConsumeConfirm {
        @SneakyThrows
        public static void main(String[] args) {
            Channel channel = MqChanneUtils.getChannel();
            DeliverCallback deliverCallback =(a, delivery)->{
                String receivedMessage = new String(delivery.getBody());
                SleepUtils.sleeper(30); //这里改下时间
                System.out.println(" 接收到消息:"+receivedMessage);
                //应答一个消息，最后false代表只应答当前消息。
                channel.basicAck(delivery.getEnvelope().getDeliveryTag(),false);
            };
            //将通道的应答机制设置手动应答
            boolean autoAck = false;
            channel.basicConsume("test01",autoAck,deliverCallback,consumer->{});
        }
    }

整个效果，01我消费第一条消息后就停掉服务，发现剩下的消息都被02消费了。![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80Mjc0MDU0MA_size_16_color_FFFFFF_t_70][]

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80Mjc0MDU0MA_size_16_color_FFFFFF_t_70]: /images/20221005/5be4c4943b494d0d879e160eca97ecb8.png