Spring cloud stream packet message []

  The last article we briefly introduced the use of stream and found still pretty easy to use, but in the last case, if there are multiple recipient of the message, then the message is the message sent by the producer will be more consumers are received this situation in some practical scenarios there is a big problem, as in the following scenario, we do cluster deployment order system will obtain order information from the RabbitMQ, that if an order to simultaneously obtain two services, then it will cause data errors, we have to avoid this. Then we can use Stream in the message packet to solve!

Stream message packet

  The role of message packet we have introduced. Note that in the Stream in the same group of consumers is more competition. It can ensure the message will be one of the first consumer applications. Different groups that can be consumed, competition will occur within the same group, only one of which can be consumed. To demonstrate through case we see, where we will create three services are as follows
| Services | Introduction |
| - |: - |
| Stream-Group-SENDER | message sender service |
| Stream-Group-receiverA | message recipients services |
| Stream-Group-receiverB | recipient of the message service |

1. Create a stream-group-sender service

1.1 Creating project

1.2 pom file

<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 http://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>1.5.13.RELEASE</version>
    </parent>
    <groupId>com.bobo</groupId>
    <artifactId>stream-group-sender</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>Dalston.SR5</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-eureka</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-stream-rabbit</artifactId>
        </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>
            </plugin>
        </plugins>
    </build>
</project>

1.3 configuration files

  Configuration "outputProduct" can be customized, but so will we in the message interface to be used.

spring.application.name=stream-sender
server.port=9060
#设置服务注册中心地址，指向另一个注册中心
eureka.client.serviceUrl.defaultZone=http://dpb:123456@eureka1:8761/eureka/,http://dpb:123456@eureka2:8761/eureka/

#rebbitmq 链接信息
spring.rabbitmq.host=192.168.88.150
spring.rabbitmq.port=5672
spring.rabbitmq.username=dpb
spring.rabbitmq.password=123
spring.rabbitmq.virtualHost=/

# 对应 MQ 是 exchange  outputProduct自定义的信息
spring.cloud.stream.bindings.outputProduct.destination=exchangeProduct

1.4 transmission interface

/**
 * 发送消息的接口
 * @author dengp
 *
 */
public interface ISendeService {
    
    String OUTPUT="outputProduct";
    

    /**
     * 指定输出的交换器名称
     * @return
     */
    @Output(OUTPUT)
    SubscribableChannel send();
}

1.5 startup class

@SpringBootApplication
@EnableEurekaClient
// 绑定我们刚刚创建的发送消息的接口类型
@EnableBinding(value={ISendeService.class})
public class StreamSenderStart {

    public static void main(String[] args) {
        SpringApplication.run(StreamSenderStart.class, args);
    }
}

1.6 Creating pojo

  Objects In this case the message we are sending is customizable

package com.bobo.stream.pojo;

import java.io.Serializable;

public class Product implements Serializable{

    private Integer id;
    
    private String name;

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public Product(Integer id, String name) {
        super();
        this.id = id;
        this.name = name;
    }

    public Product() {
        super();
    }

    @Override
    public String toString() {
        return "Product [id=" + id + ", name=" + name + "]";
    }
    
}

2. Create stream-group-receiverA Service

2.1 Creating project

2.2 pom file

<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 http://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>1.5.13.RELEASE</version>
    </parent>
    <groupId>com.bobo</groupId>
    <artifactId>stream-group-receiverA</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>Dalston.SR5</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-eureka</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-stream-rabbit</artifactId>
        </dependency>
    </dependencies>
    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>
</project>

2.3 configuration files

  Profile configuration packets "groupProduct"

spring.application.name=stream-group-receiverA
server.port=9070
#设置服务注册中心地址，指向另一个注册中心
eureka.client.serviceUrl.defaultZone=http://dpb:123456@eureka1:8761/eureka/,http://dpb:123456@eureka2:8761/eureka/

#rebbitmq 链接信息
spring.rabbitmq.host=192.168.88.150
spring.rabbitmq.port=5672
spring.rabbitmq.username=dpb
spring.rabbitmq.password=123
spring.rabbitmq.virtualHost=/

# 对应 MQ 是 exchange  和消息发送者的 交换器是同一个
spring.cloud.stream.bindings.inputProduct.destination=exchangeProduct
# 具体分组 对应 MQ 是 队列名称 并且持久化队列  inputProduct 自定义
spring.cloud.stream.bindings.inputProduct.group=groupProduct

An interface to receive messages 2.4

/**
 * 接收消息的接口
 * @author dengp
 *
 */
public interface IReceiverService {

    String INPUT = "inputProduct";
    /**
     * 指定接收的交换器名称
     * @return
     */
    @Input(INPUT)
    SubscribableChannel receiver();
}

DETAILED message handler class 2.5

/**
 * 具体接收消息的处理类
 * @author dengp
 *
 */
@Service
@EnableBinding(IReceiverService.class)
public class ReceiverService {

    @StreamListener(IReceiverService.INPUT)
    public void onReceiver(Product p){
        System.out.println("消费者A:"+p);
    }
}

Note also need to add a Product categories

package com.bobo.stream.pojo;

import java.io.Serializable;

public class Product implements Serializable{

    private Integer id;
    
    private String name;

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public Product(Integer id, String name) {
        super();
        this.id = id;
        this.name = name;
    }

    public Product() {
        super();
    }

    @Override
    public String toString() {
        return "Product [id=" + id + ", name=" + name + "]";
    }
    
}

2.6 startup class

@SpringBootApplication
@EnableEurekaClient
@EnableBinding(value={IReceiverService.class})
public class StreamReceiverStart {

    public static void main(String[] args) {
        SpringApplication.run(StreamReceiverStart.class, args);
    }
}

3. Create a stream-group-receiverB Service

  This service and stream-group-receiverA as a copy application.properties simply modify the service name, port. We do not set the same first group, we test to see

spring.application.name=stream-group-receiverB
server.port=9071
#设置服务注册中心地址，指向另一个注册中心
eureka.client.serviceUrl.defaultZone=http://dpb:123456@eureka1:8761/eureka/,http://dpb:123456@eureka2:8761/eureka/

#rebbitmq 链接信息
spring.rabbitmq.host=192.168.88.150
spring.rabbitmq.port=5672
spring.rabbitmq.username=dpb
spring.rabbitmq.password=123
spring.rabbitmq.virtualHost=/

# 对应 MQ 是 exchange  和消息发送者的 交换器是同一个
spring.cloud.stream.bindings.inputProduct.destination=exchangeProduct
# 具体分组 对应 MQ 是 队列名称 并且持久化队列  inputProduct 自定义
spring.cloud.stream.bindings.inputProduct.group=groupProduct1

4. Test Code

@RunWith(SpringRunner.class)
@SpringBootTest(classes=StreamSenderStart.class)
public class StreamTest {
    
    @Autowired
    private ISendeService sendService;

    @Test
    public void testStream(){
        Product p = new Product(666, "stream test ...");
        // 将需要发送的消息封装为Message对象
        Message message = MessageBuilder
                                .withPayload(p)
                                .build();
        sendService.send().send(message );
    }
}

In the case of inconsistencies group stream-group-receiverA and stream-group-receiverB services

The case was changed to the same group

Start the service, to send data

The results can be seen only by being one of the message. Avoiding duplicate messages consumption .

Case Code github: https: //github.com/q279583842q/springcloud-e-book