Java微服务(二):服务消费者与提供者搭建
本文接着上一篇写的《Java微服务(一):dubbo-admin控制台的使用》,上篇文章介绍了docker,zookeeper环境的安装,并参考dubbo官网演示了dubbo-admin控制台的使用。上篇文章已经搭建好zookeeper服务注册中心,本片文章主要搭建服务消费者和服务提供者。按照微服务的原则,本文将demo分为3部分:服务接口、服务消费者、服务消费者。
服务接口:定义了系统所需要的全部接口。
服务提供者:主要是对接口的实现。
服务消费者:对接口的使用
1.Dubbo介绍
节点 | 角色说明 |
---|---|
Provider |
暴露服务的服务提供方 |
Consumer |
调用远程服务的服务消费方 |
Registry |
服务注册与发现的注册中心 |
Monitor |
统计服务的调用次数和调用时间的监控中心 |
Container |
服务运行容器 |
Dubbo 架构具有以下几个特点,分别是连通性、健壮性、伸缩性、以及向未来架构的升级性。
调用关系说明
- 服务容器负责启动,加载,运行服务提供者。
- 服务提供者在启动时,向注册中心注册自己提供的服务。
- 服务消费者在启动时,向注册中心订阅自己所需的服务。
- 注册中心返回服务提供者地址列表给消费者,如果有变更,注册中心将基于长连接推送变更数据给消费者。
- 服务消费者,从提供者地址列表中,基于软负载均衡算法,选一台提供者进行调用,如果调用失败,再选另一台调用。
- 服务消费者和提供者,在内存中累计调用次数和调用时间,定时每分钟发送一次统计数据到监控中心。
Dubbo 架构具有以下几个特点,分别是连通性、健壮性、伸缩性、以及向未来架构的升级性。
更详细的介绍,请参考官网:http://dubbo.apache.org/en-us/
2.服务接口
通过idea创建一个jar工程,创建工程的过程可以参考《Spring boot 入门(一):快速搭建Spring boot项目》,此工程的目的只是简单的定义接口,所以这里直接创建jar包,不是maven工程。创建好了后,新建一个接口。以下是我创建的接口:
其中UserService代码如下:
1 package com.edu.hello.dubbo.service.user.api; 2 3 public interface UserService { 4 String sayHi(); 5 }
创建完接口后,需要把接口install到本地仓库,供服务消费者和服务提供者使用
在Terminal直接指向mvn clean install或者直接在lifecycle目录下点击install进行安装,出现如下页面,表示安装成功
3.服务提供者
服务提供者主要是对接口的实现,用相同的方法创建一个maven工程,创建好后的maven工程目录如下:
其中UserServicelmpl是多接口的实现,代码如下:
1 package com.edu.hello.dubbo.service.user.provider.api.impl; 2 3 import com.alibaba.dubbo.config.annotation.Service; 4 import com.edu.hello.dubbo.service.user.api.UserService; 5 import com.netflix.hystrix.contrib.javanica.annotation.HystrixCommand; 6 import com.netflix.hystrix.contrib.javanica.annotation.HystrixProperty; 7 import org.springframework.beans.factory.annotation.Value; 8 9 /** 10 * @ClassName UserServiceImpl 11 * @Deccription TODO 12 * @Author DZ 13 * @Date 2019/8/31 11:20 14 **/ 15 @Service(version = "${user.service.version}") 16 public class UserServiceImpl implements UserService { 17 18 @Value("${dubbo.protocol.port}") 19 private String port; 20 21 /*@HystrixCommand(commandProperties = { 22 @HystrixProperty(name = "circuitBreaker.requestVolumeThreshold", value = "10"), 23 @HystrixProperty(name = "execution.isolation.thread.timeoutInMilliseconds", value = "2000") 24 })*/ 25 @Override 26 public String sayHi() { 27 return "Say Hello, i am from " + port; 28 } 29 }
其中@HystrixCommand注解在后面熔断器中会讲到,这里先注释。
yml配置如下:
1 spring: 2 application: 3 name: hello-dubbo-service-user-provider 4 5 user: 6 service: 7 version: 1.0.0 8 9 dubbo: 10 scan: 11 basePackages: com.edu.hello.dubbo.service.user.provider.api 12 application: 13 id: hello-dubbo-service-user-provider 14 name: hello-dubbo-service-user-provider 15 qos-port: 22222 16 qos-enable: true 17 protocol: 18 id: dubbo 19 name: dubbo 20 port: 12346 21 status: server 22 serialization: kryo #高速序列化 23 # optimizer: 24 25 registry: 26 id: zookeeper 27 address: zookeeper://192.168.1.12:2181?back=192.168.1.12:2182,192.168.1.12:2183 28 provider: 29 loadbalance: roundrobin #负载均衡 30 31 32 33 management: 34 endpoint: 35 dubbo: 36 enable: true 37 dubbo-shutdown: 38 enabled: true 39 dubbo-configs: 40 enabled: true 41 dubbo-services: 42 enabled: true 43 dubbo-references: 44 enabled: true 45 dubbo-peoperties: 46 enabled: true 47 health: 48 dubbo: 49 status: 50 defaults: memory 51 extras: load,threadpool
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pom文件如下:
1 <?xml version="1.0" encoding="UTF-8"?> 2 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 3 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd"> 4 <modelVersion>4.0.0</modelVersion> 5 <parent> 6 <groupId>org.springframework.boot</groupId> 7 <artifactId>spring-boot-starter-parent</artifactId> 8 <version>2.1.7.RELEASE</version> 9 <relativePath/> <!-- lookup parent from repository --> 10 </parent> 11 <groupId>com.edu</groupId> 12 <artifactId>hello-dubbo-service-user-provider</artifactId> 13 <version>1.0.0-SNAPSHOT</version> 14 <name>hello-dubbo-service-user-provider</name> 15 <description>Demo project for Spring Boot</description> 16 17 <properties> 18 <java.version>1.8</java.version> 19 </properties> 20 21 <dependencies> 22 <dependency> 23 <groupId>org.springframework.boot</groupId> 24 <artifactId>spring-boot-starter</artifactId> 25 </dependency> 26 <dependency> 27 <groupId>org.springframework.boot</groupId> 28 <artifactId>spring-boot-starter-actuator</artifactId> 29 </dependency> 30 <dependency> 31 <groupId>org.springframework.boot</groupId> 32 <artifactId>spring-boot-starter-test</artifactId> 33 <scope>test</scope> 34 </dependency> 35 <dependency> 36 <groupId>com.alibaba.boot</groupId> 37 <artifactId>dubbo-spring-boot-starter</artifactId> 38 <version>0.2.0</version> 39 </dependency> 40 <dependency> 41 <groupId>com.edu</groupId> 42 <artifactId>hello-dubbo-service-user-api</artifactId> 43 <version>${project.version}</version> 44 </dependency> 45 <dependency> 46 <groupId>de.javakaffee</groupId> 47 <artifactId>kryo-serializers</artifactId> 48 <version>0.42</version> 49 </dependency> 50 <!-- https://mvnrepository.com/artifact/org.springframework.cloud/spring-cloud-starter-hystrix --> 51 <!-- https://mvnrepository.com/artifact/org.springframework.cloud/spring-cloud-starter-netflix-hystrix --> 52 <dependency> 53 <groupId>org.springframework.cloud</groupId> 54 <artifactId>spring-cloud-starter-netflix-hystrix</artifactId> 55 <version>2.0.1.RELEASE</version> 56 </dependency> 57 <!-- https://mvnrepository.com/artifact/org.springframework.cloud/spring-cloud-starter-netflix-hystrix-dashboard --> 58 <dependency> 59 <groupId>org.springframework.cloud</groupId> 60 <artifactId>spring-cloud-starter-netflix-hystrix-dashboard</artifactId> 61 <version>2.0.1.RELEASE</version> 62 </dependency> 63 64 65 66 </dependencies> 67 68 <build> 69 <plugins> 70 <plugin> 71 <groupId>org.springframework.boot</groupId> 72 <artifactId>spring-boot-maven-plugin</artifactId> 73 </plugin> 74 </plugins> 75 </build> 76 77 </project>
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本文pom文件和yml文件主要是根据dubbo官网中服务提供者的pom文件中的依赖而来,具体参考:https://github.com/apache/dubbo-spring-boot-project/tree/master/dubbo-spring-boot-samples/dubbo-registry-zookeeper-samples。
注意basePackages注解
4.服务提供者
按照相同的方式创建服务提供者,配置文件和服务提供者也类似,直接贴代码了
1 package com.edu.hello.dubbo.service.user.consumer.controller; 2 3 4 import com.alibaba.dubbo.config.annotation.Reference; 5 import com.edu.hello.dubbo.service.user.api.UserService; 6 import com.netflix.hystrix.contrib.javanica.annotation.HystrixCommand; 7 import org.springframework.web.bind.annotation.RequestMapping; 8 import org.springframework.web.bind.annotation.RequestMethod; 9 import org.springframework.web.bind.annotation.RestController; 10 11 /** 12 * @ClassName UserController 13 * @Deccription TODO 14 * @Author DZ 15 * @Date 2019/8/31 18:37 16 **/ 17 @RestController 18 public class UserController { 19 20 @Reference(version = "${user.service.version}") 21 private UserService userService; 22 23 @HystrixCommand(fallbackMethod = "sayHiError") 24 @RequestMapping(value = "hi", method = RequestMethod.GET) 25 public String sayHi() { 26 return userService.sayHi(); 27 } 28 29 public String sayHiError() { 30 return "Hystrix fallback"; 31 } 32 }
yml配置文件和pom配置文件和提供者基本类似;
1 spring: 2 application: 3 name: hello-dubbo-service-user-consumer 4 5 user: 6 service: 7 version: 1.0.0 8 9 dubbo: 10 scan: 11 basePackages: com.edu.hello.dubbo.service.user.consumer.controller 12 application: 13 id: hello-dubbo-service-user-consumer 14 name: hello-dubbo-service-user-consumer 15 qos-port: 22223 16 qos-enable: true 17 protocol: 18 id: dubbo 19 name: dubbo 20 port: 12345 21 #status: server 22 serialization: kryo 23 registry: 24 id: zookeeper 25 address: zookeeper://192.168.1.12:2181?back=192.168.1.12:2182,192.168.1.12:2183 26 27 28 management: 29 endpoint: 30 dubbo: 31 enable: true 32 dubbo-shutdown: 33 enabled: true 34 dubbo-configs: 35 enabled: true 36 dubbo-services: 37 enabled: true 38 dubbo-references: 39 enabled: true 40 dubbo-peoperties: 41 enabled: true 42 health: 43 dubbo: 44 status: 45 defaults: memory 46 extras: load,threadpool 47 server: 48 port: 9090
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1 <?xml version="1.0" encoding="UTF-8"?> 2 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 3 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd"> 4 <modelVersion>4.0.0</modelVersion> 5 <parent> 6 <groupId>org.springframework.boot</groupId> 7 <artifactId>spring-boot-starter-parent</artifactId> 8 <version>2.1.7.RELEASE</version> 9 <relativePath/> <!-- lookup parent from repository --> 10 </parent> 11 <groupId>com.edu</groupId> 12 <artifactId>hello-dubbo-service-user-consumer</artifactId> 13 <version>1.0.0-SNAPSHOT</version> 14 <name>hello-dubbo-service-user-consumer</name> 15 <description>Demo project for Spring Boot</description> 16 17 <properties> 18 <java.version>1.8</java.version> 19 </properties> 20 21 <dependencies> 22 <dependency> 23 <groupId>org.springframework.boot</groupId> 24 <artifactId>spring-boot-starter-web</artifactId> 25 </dependency> 26 <dependency> 27 <groupId>org.springframework.boot</groupId> 28 <artifactId>spring-boot-starter-actuator</artifactId> 29 </dependency> 30 <dependency> 31 <groupId>org.springframework.boot</groupId> 32 <artifactId>spring-boot-starter-test</artifactId> 33 <scope>test</scope> 34 </dependency> 35 <dependency> 36 <groupId>com.alibaba.boot</groupId> 37 <artifactId>dubbo-spring-boot-starter</artifactId> 38 <version>0.2.0</version> 39 </dependency> 40 <dependency> 41 <groupId>com.edu</groupId> 42 <artifactId>hello-dubbo-service-user-api</artifactId> 43 <version>${project.version}</version> 44 </dependency> 45 <dependency> 46 <groupId>de.javakaffee</groupId> 47 <artifactId>kryo-serializers</artifactId> 48 <version>0.42</version> 49 </dependency> 50 <!-- https://mvnrepository.com/artifact/org.springframework.cloud/spring-cloud-starter-hystrix --> 51 <!-- https://mvnrepository.com/artifact/org.springframework.cloud/spring-cloud-starter-netflix-hystrix --> 52 <dependency> 53 <groupId>org.springframework.cloud</groupId> 54 <artifactId>spring-cloud-starter-netflix-hystrix</artifactId> 55 <version>2.0.1.RELEASE</version> 56 </dependency> 57 <!-- https://mvnrepository.com/artifact/org.springframework.cloud/spring-cloud-starter-netflix-hystrix-dashboard --> 58 <dependency> 59 <groupId>org.springframework.cloud</groupId> 60 <artifactId>spring-cloud-starter-netflix-hystrix-dashboard</artifactId> 61 <version>2.0.1.RELEASE</version> 62 </dependency> 63 </dependencies> 64 65 <build> 66 <plugins> 67 <plugin> 68 <groupId>org.springframework.boot</groupId> 69 <artifactId>spring-boot-maven-plugin</artifactId> 70 <configuration> 71 <mainClass>com.edu.hello.dubbo.service.user.consumer.HelloDubboServiceUserConsumerApplication</mainClass> 72 </configuration> 73 </plugin> 74 </plugins> 75 </build> 76 77 </project>
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这里面关于服务熔断和负载均衡的的代码可以暂时不关注,后面会专门对熔断进行讨论。
5.结果
分别启动服务消费者和服务提供者,启动成功后,如下:
同时我们可以启动dubbo-admin控制台查看服务,注意端口的冲突: