SpringCloud Stream消息驱动
消息驱动概述
屏蔽底层消息中间件的差异,降低切换版本,统一消息的编程模型
![1597388512890]()
![1597388531508]()
Spring Cloud Stream中文指导手册
https://m.wang1314.com/doc/webapp/topic/20971999.html
设计思想
标准MQ
![1597828873174]()
生产者/消费者之间靠消息媒介传递信息内容:\
Message
消息必须走特定的通道
消息通道MessageChannel
消息通道里的消息如何被消费呢,谁负责收发处理:
消息通道MessageChannel的子接口SubscribableChannel,由MessageHandler消息处理器订阅
为什么用Cloud Stream
![1598076856767]()
![1598076876160]()
![1598076887339]()
stream凭什么可以统一底层差异
![1597828959376]()
![1597828966885]()
Binder
![1597828986684]()
![1597828994579]()
![1597829004031]()
INPUT对应于消费者
OUTPUT对应于生产者
Stream中的消息通信方式遵循了发布-订阅模式
Topic主题进行广播
在RabbitMQ就是Exchange
在kafka中就是Topic
Spring Cloud Stream标准流程套路
![1597829077773]()
![1597829087752]()
Binder
很方便的连接中间件,屏蔽差异
Channel
通道,是队列Queue的一种抽象,在消息通讯系统中就是实现存储和转发的媒介,通过对Channel对队列进行配置
Source和Sink
简单的可理解为参照对象是Spring Cloud Stream自身,从Stream发布消息就是输出,接受消息就是输入
编码API和常用注解
![1597829175675]()
案例说明
RabbitMQ环境已经OK
工程中新建三个子模块
cloud-stream-rabbitmq-provider8801,作为生产者进行发消息模块
cloud-stream-rabbitmq-consumer8802,作为消息接收模块
cloud-stream-rabbitmq-consumer8803,作为消息接收模块
消息驱动之生产者
新建Module
cloud-stream-rabbitmq-provider8801
pom
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54
| <dependencies> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-stream-rabbit</artifactId> </dependency>
<dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId> </dependency>
<dependency> <groupId>com.kayleh.springcloud</groupId> <artifactId>cloud-api-commons</artifactId> <version>${project.version}</version> </dependency>
<dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency>
<dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-actuator</artifactId> </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>
|
yaml
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| server: port: 8801
spring: application: name: cloud-stream-provider cloud: stream: binders: defaultRabbit: type: rabbit environment: spring: rabbitmq: host: localhost port: 5672 username: guest password: guest bindings: output: destination: studyExchange content-type: application/json binder: defaultRabbit
eureka: client: service-url: defaultZone: http://localhost:7001/eureka instance: lease-renewal-interval-in-seconds: 2 lease-expiration-duration-in-seconds: 5 instance-id: send-8801.com prefer-ip-address: true
|
主启动类StreamMQMain8801
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| package com.kayleh.springcloud;
import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication;
@SpringBootApplication public class StreamMQMain8801 { public static void main(String[] args) { SpringApplication.run(StreamMQMain8801.class, args); } }
|
业务类
发送消息接口
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| package com.kayleh.springcloud.service;
public interface IMessageProvider { public String send(); }
|
发送消息接口实现类
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| package com.kayleh.springcloud.service.impl;
@EnableBinding(Source.class) public class MessageProviderImpl implements IMessageProvider { @Resource private MessageChannel output;
@Override public String send() { String serial = UUID.randomUUID().toString(); output.send(MessageBuilder.withPayload(serial).build()); System.out.println("*****serial: "+serial); return null; } }
|
Controller
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| package com.kayleh.springcloud.controller;
import com.kayleh.springcloud.service.IMessageProvider; import org.springframework.web.bind.annotation.GetMapping; import org.springframework.web.bind.annotation.RestController;
import javax.annotation.Resource;
@RestController public class SendMessageController { @Resource private IMessageProvider messageProvider;
@GetMapping(value = "/sendMessage") public String sendMessage() { return messageProvider.send(); } }
|
测试
启动7001eureka
启动rabbitmq:
rabbitmq-plugins enable rabbitmq_management
http://localhost:15672/
启动8801
访问http://localhost:8801/sendMessage
消息驱动之消费者
新建Module
cloud-stream-rabbitmq-consumer8802
pom
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54
| <dependencies> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-stream-rabbit</artifactId> </dependency>
<dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId> </dependency>
<dependency> <groupId>com.kayleh.springcloud</groupId> <artifactId>cloud-api-commons</artifactId> <version>${project.version}</version> </dependency>
<dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency>
<dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-actuator</artifactId> </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>
|
yml
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| server: port: 8802
spring: application: name: cloud-stream-consumer cloud: stream: binders: defaultRabbit: type: rabbit environment: spring: rabbitmq: host: localhost port: 5672 username: guest password: guest bindings: input: destination: studyExchange content-type: application/json binder: defaultRabbit
eureka: client: service-url: defaultZone: http://localhost:7001/eureka instance: lease-renewal-interval-in-seconds: 2 lease-expiration-duration-in-seconds: 5 instance-id: receive-8802.com prefer-ip-address: true
|
主启动类StreamMQMain8802
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| package com.kayleh.springcloud;
import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication;
@SpringBootApplication public class StreamMQMain8802 {
public static void main(String[] args) { SpringApplication.run(StreamMQMain8802.class, args); } }
|
controller
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| package com.kayleh.springcloud.controller;
import org.springframework.cloud.stream.annotation.StreamListener; import org.springframework.messaging.Message; import org.springframework.beans.factory.annotation.Value; import org.springframework.cloud.stream.annotation.EnableBinding; import org.springframework.cloud.stream.messaging.Sink; import org.springframework.stereotype.Component;
@Component @EnableBinding(Sink.class) public class ReceiveMessageListenerController { @Value("${server.port}") private String serverPort;
@StreamListener(Sink.INPUT) public void input(Message<String> message) { System.out.println("消费者1号,接受:"+message.getPayload()+"\t port:"+serverPort); } }
|
测试8801发送8802接收消息
http://localhost:8801/sendMessage
分组消费与持久化
依照8802,clone出来一份运行8803
cloud-stream-rabbitmq-consumer8803
pom
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36
| <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-netflix-eureka-client</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-actuator</artifactId> </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>
|
yaml
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| server: port: 8803
spring: application: name: cloud-stream-consumer cloud: stream: binders: defaultRabbit: type: rabbit environment: spring: rabbitmq: host: localhost port: 5672 username: guest password: guest bindings: input: destination: studyExchange content-type: application/json binder: defaultRabbit group: kaylehA
eureka: client: service-url: defaultZone: http://localhost:7001/eureka instance: lease-renewal-interval-in-seconds: 2 lease-expiration-duration-in-seconds: 5 instance-id: receive-8803.com prefer-ip-address: true
|
主启动类
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| package com.kayleh.springcloud;
import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication;
@SpringBootApplication public class StreamMQMain8803 { public static void main(String[] args) { SpringApplication.run(StreamMQMain8803.class,args); } }
|
业务类
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| package com.kayleh.springcloud.controller;
import org.springframework.beans.factory.annotation.Value; import org.springframework.cloud.stream.annotation.EnableBinding; import org.springframework.cloud.stream.annotation.StreamListener; import org.springframework.cloud.stream.messaging.Sink; import org.springframework.messaging.Message; import org.springframework.stereotype.Component; @Component @EnableBinding(Sink.class) public class ReceiveMessageListenerController { @Value("${server.port}") private String serverPort;
@StreamListener(Sink.INPUT) public void input(Message<String> message) { System.out.println("消费者2号,----->接受到的消息: "+message.getPayload()+"\t port: "+serverPort); } }
|
启动
7001服务注册
8801消息生产
8802消息消费
8803消息消费
运行后两个问题
有重复消费问题
消息持久化问题
消费
目前是8802/8803同时都收到了,存在重复消费问题
http://localhost:8801/sendMessage
如何解决?
分组和持久化属性group
重要
生产实际案例
![1597830160806]()
![1597830172304]()
分组
原理
微服务应用放置于
同一个group中,就能够保证消息只会被其中一个应用消费一次。
不同的组是可以消费的,同一个组内会发生竞争关系,只有其中一个可以消费。
8802/8803都变成不同组,group两个不同
group: kaylehA、kaylehB
8802修改YML
在binder下面添加
8803修改YML
我们自己配置
![1597830340659]()
结论
还是重复消费
8802/8803实现了轮询分组,每次只有一个消费者 8801模块的发的消息只能被8802或8803其中一个接收到,这样避免了重复消费
8802/8803都变成相同组,group两个相同
group: kaylehA
8802修改YML
8803修改YML
结论
同一个组的多个微服务实例,每次只会有一个拿到
持久化
通过上述,解决了重复消费问题,再看看持久化
停止8802/8803并去除掉8802的分组group:kaylehA
8803的分组group:kaylehA没有去掉
8801先发送4条信息到rabbitmq
先启动8802,无分组属性配置,后台没有打出来消息
先启动8803,有分组属性配置,后台打出来了MQ上的消息