spring 雲 stream 供應商和消費者未觸發

Question

我正在使用 spring 雲 stream 的函數式編程 model 來聲明供應商和消費者。
我需要我的發布者每秒被觸發一次，然后消息由處理器處理，最后由消費者使用。 但這些功能永遠不會被觸發。 是否缺少任何配置？

這是我的代碼：-

spring 引導 App Main class

import java.util.Date;
import java.util.Properties;
import java.util.function.Consumer;
import java.util.function.Function;
import java.util.function.Supplier;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.Bean;

@SpringBootApplication
public class Example1 {

    public static void main(String[] args) {

        Properties properties = new Properties();

        properties.put("spring.cloud.stream.bindings.myPublisher-out-0.destination", "myProcessor-in");
        properties.put("spring.cloud.stream.bindings.myProcessor-in-0.destination", "myProcessor-in");
        properties.put("spring.cloud.stream.bindings.myProcessor-out-0.destination", "myProcessor-out");
        properties.put("spring.cloud.stream.bindings.mySubscriber-in-0.destination", "myProcessor-out");

        SpringApplication app = new SpringApplication(Example1.class);
        app.setDefaultProperties(properties);
        app.run(args);

    }

    @Bean
    public Supplier<String> myPublisher() {
        return () -> new Date().toString();
    }

    @Bean
    public Function<String, String> myProcessor() {
        return s -> "ML PROCESSED: " + s;
    }

    @Bean
    public Consumer<String> mySubscriber() {
        return s -> System.out.println("ML RECEIVED: " + s);
    }
}

pom.xml 文件

<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>
    <groupId>org.javaworld</groupId>
    <artifactId>code-snippet</artifactId>
    <version>0.0.1-SNAPSHOT</version>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.5.2</version>
        <relativePath /> <!-- lookup parent from repository -->
    </parent>
    
    <properties>
        <spring-cloud.version>2021.0.2</spring-cloud.version>
    </properties>
    
    <dependencies>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-webflux</artifactId>
            <!-- 
            <scope>test</scope>
             -->
        </dependency>
        
        <!-- https://mvnrepository.com/artifact/org.hibernate/hibernate-core -->
        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-core</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>
         
        <!-- C3P0 connection pool dependencies -->
        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-c3p0</artifactId>
        </dependency>

        <dependency>
            <groupId>com.mchange</groupId>
            <artifactId>c3p0</artifactId>
            <version>0.9.5.1</version>
        </dependency>

        <!-- Hikari connection pool dependencies -->
        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-hikaricp</artifactId>
        </dependency>

        <dependency>
            <groupId>com.zaxxer</groupId>
            <artifactId>HikariCP</artifactId>
        </dependency>

        <!-- actuators support -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>

        <dependency>
            <groupId>io.dropwizard.metrics</groupId>
            <artifactId>metrics-core</artifactId>
        </dependency>

        <!-- ################################ JMS using activemq support ######################################## -->
        <!--  -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-activemq</artifactId>
        </dependency>
        
        <!-- needed when running JMS without any framework..specifically the 
        examples in this package spring_boot._4_jms.no_framework  -->
        
        <dependency>
            <groupId>org.apache.activemq</groupId>
            <artifactId>activemq-kahadb-store</artifactId>
            <scope>runtime</scope>
        </dependency>
        
        <!--  the above spring-boot-starter-activemq replaces all these following dependencies -->
        
        <!-- 
        
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-configuration-processor</artifactId>
            <optional>true</optional>
        </dependency>
        
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-jms</artifactId>
        </dependency>

        <dependency>
            <groupId>org.apache.activemq</groupId>
            <artifactId>activemq-client</artifactId>
        </dependency>
        -->
        
        <!-- ################################ AMQP support ######################################## -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-amqp</artifactId>
        </dependency>

        <!-- ################################ Wiremock support #################################### -->
        <dependency>
            <groupId>com.github.tomakehurst</groupId>
            <artifactId>wiremock-jre8</artifactId>
            <version>2.32.0</version>
            <scope>test</scope>
        </dependency>
        
        <!-- ################################ Spring cloud stream ###################################### -->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-stream</artifactId>
        </dependency>
            
    </dependencies>
    
    <!-- for spring cloud stream support -->
    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>${spring-cloud.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>
</project>

Answer 1

您應該為spring-cloud-stream定義您的Function 、 Supplier和Consumer ，如下所示。

properties.put("spring.cloud.stream.function.definition", "myPublisher;myProcessor;mySubscriber");