本篇概览
- 本文是《dubbo实战》系列的第三篇,主要内容是使用Zookeeper作为注册中心的实战;
- 前面两篇的实战都是使用了广播模式,整个环境由服务提供者和服务消费者组成,这种简单形态只是为了方便学习,实际上多数情况都会部署注册中心,服务提供者在上面注册,服务消费者再从注册中心得到具体的服务信息;
- 下面是个典型的提供者、消费者、注册中心的典型架构图:
- 如下图所示,dubbo官方推荐的注册中心是<font color="blue">Zookeeper</font>:
关于Zookeeper
- 本次使用了单节点Zookeeper,版本<font color="red">3.4.13</font>,IP<font color="blue">192.168.50.43</font>,端口<font color="blue">2181</font>
- 关于Zookeeper的部署,我这边是通过docker快速部署的,参考文章《群晖DS218+部署kafka》
- 如果您部署好了Zookeeper,接下来开始编写服务提供者和消费者的代码;
源码下载
- 如果您不想编码,可以在GitHub下载所有源码,地址和链接信息如下表所示:
名称 | 链接 | 备注 |
---|---|---|
项目主页 | https://github.com/zq2599/blog_demos | 该项目在GitHub上的主页 |
git仓库地址(https) | https://github.com/zq2599/blog_demos.git | 该项目源码的仓库地址,https协议 |
git仓库地址(ssh) | git@github.com:zq2599/blog_demos.git | 该项目源码的仓库地址,ssh协议 |
- 这个git项目中有多个文件夹,本章的应用在<font color="blue">dubbopractice</font>文件夹下,如下图红框所示:
3. <font color="blue">dubbopractice</font>是父子结构的工程,本篇的代码在<font color="red">springbootzkprovider</font>和<font color="red">springbootzkconsumer</font>这两个子工程中,如下图:
编码(服务提供方)
- 先创建提供服务的工程<font color="blue">springbootmulticastprovider</font>,一共要创建4个文件,创建顺序和功能如下表:
创建顺序 | 文件名 | 作用 |
---|---|---|
1 | pom.xml | 工程的pom文件 |
2 | src/main/resources/application.yml | 配置文件 |
3 | DemoServiceImpl.java | 提供具体的服务 |
4 | SpringBootZKProviderApplication.java | 启动类 |
- 完整的文件位置如下图:
- 接下来逐个创建上述内容;
- 创建名为<font color="blue">springbootmulticastprovider</font>的子工程,pom.xml内容如下,要重点关注的是新增依赖<font color="blue">dubbo-spring-boot-starter</font>,这就是dubbo在SpringBoot环境的starter依赖,还有Zookeeper的依赖<font color="blue">dubbo-dependencies-zookeeper</font>:
<?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 http://maven.apache.org/xsd/maven-4.0.0.xsd"> <parent> <artifactId>dubbopractice</artifactId> <groupId>com.bolingcavalry</groupId> <version>1.0-SNAPSHOT</version> </parent> <modelVersion>4.0.0</modelVersion> <groupId>com.bolingcavalry</groupId> <artifactId>springbootzkprovider</artifactId> <version>1.0-SNAPSHOT</version> <name>springbootzkprovider</name> <description>Demo project for dubbo service provider from Spring Boot</description> <!--不用spring-boot-starter-parent作为parent时的配置--> <dependencyManagement> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-dependencies</artifactId> <version>2.3.3.RELEASE</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.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> <dependency> <groupId>com.bolingcavalry</groupId> <artifactId>practiceinterface</artifactId> <version>${project.version}</version> </dependency> <dependency> <groupId>org.apache.dubbo</groupId> <artifactId>dubbo-dependencies-zookeeper</artifactId> <type>pom</type> </dependency> <dependency> <groupId>org.projectlombok</groupId> <artifactId>lombok</artifactId> </dependency> <dependency> <groupId>org.apache.dubbo</groupId> <artifactId>dubbo-spring-boot-starter</artifactId> </dependency> </dependencies> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> <version>${springboot.version}</version> </plugin> </plugins> </build> </project>
- 配置文件<font color="blue">application.yml</font>,要注意的是registry.address的值<font color="red">zookeeper://192.168.50.43:2181</font>,这就是Zookeeper注册中心的配置:
dubbo: application: #application-name 本模块名字 name: springboot-zk-provider registry: address: zookeeper://192.168.50.43:2181 protocol: name: dubbo port: 20880
- 编写服务实现类<font color="blue">DemoServiceImpl.java</font>,注意<font color="red">@Service</font>注解将当前类的实例作为远程服务对外暴露:
package com.bolingcavalry.springbootzkprovider; import com.bolingcavalry.dubbopractice.service.DemoService; import lombok.extern.slf4j.Slf4j; import org.apache.dubbo.config.annotation.Service; import org.apache.dubbo.rpc.RpcContext; @Slf4j @Service public class DemoServiceImpl implements DemoService { @Override public String sayHello(String name) { log.info("I'm springboot-zk-provider, Hello " + name + ", request from consumer: " + RpcContext.getContext().getRemoteAddress()); try { Thread.sleep(1000); } catch (InterruptedException e) { e.printStackTrace(); } return "I'm springboot-zk-provider, Hello " + name + ", response from provider: " + RpcContext.getContext().getLocalAddress(); } }
- 编写SpringBoot启动类<font color="blue">SpringBootZKProviderApplication.java</font>,注意要添加<font color="red">@EnableDubbo注解</font>:
package com.bolingcavalry.springbootzkprovider; import org.apache.dubbo.config.spring.context.annotation.EnableDubbo; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; @SpringBootApplication @EnableDubbo public class SpringBootZKProviderApplication { public static void main(String[] args) { SpringApplication.run(SpringBootZKProviderApplication.class, args); } }
- 至此服务提供方编码完成,直接在IDEA上运行<font color="blue">SpringBootZKProviderApplication</font>类即可启动服务,启动成功后的日志输出如下图,如红框所示,已连上了Zookeeper:
编码(服务消费方)
- 现在网络上已经有了服务,咱们再来编写服用消费方的代码,一共要创建6个文件,创建顺序和功能如下表:
创建顺序 | 文件名 | 作用 |
---|---|---|
1 | pom.xml | 工程的pom文件 |
2 | src/main/resources/application.yml | 配置文件 |
3 | RemoteInvokeServiceImpl.java | service层,在这里远程调用服务提供方的服务 |
4 | DemoController.java | web接口类,对外提供web服务 |
5 | SwaggerConfig.java | swagger配置类,便于通过页面测试接口 |
6 | SpringBootZKConsumerApplication.java | 启动类 |
- 完整的文件位置如下图:
- 接下来逐个创建上述文件;
- 创建名为<font color="blue">springbootzkconsumer</font>的子工程,pom.xml内容如下,同样需要依赖<font color="blue">dubbo-spring-boot-starter</font>和<font color="blue">dubbo-dependencies-zookeeper</font>:
<?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 http://maven.apache.org/xsd/maven-4.0.0.xsd"> <parent> <artifactId>dubbopractice</artifactId> <groupId>com.bolingcavalry</groupId> <version>1.0-SNAPSHOT</version> </parent> <modelVersion>4.0.0</modelVersion> <groupId>com.bolingcavalry</groupId> <artifactId>springbootzkconsumer</artifactId> <version>1.0-SNAPSHOT</version> <name>springbootzkconsumer</name> <description>Demo project for dubbo service consumer from Spring Boot</description> <!--不用spring-boot-starter-parent作为parent时的配置--> <dependencyManagement> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-dependencies</artifactId> <version>2.3.3.RELEASE</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.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> <!-- swagger依赖 --> <dependency> <groupId>io.springfox</groupId> <artifactId>springfox-swagger2</artifactId> </dependency> <!-- swagger-ui --> <dependency> <groupId>io.springfox</groupId> <artifactId>springfox-swagger-ui</artifactId> </dependency> <dependency> <groupId>com.bolingcavalry</groupId> <artifactId>practiceinterface</artifactId> <version>${project.version}</version> </dependency> <dependency> <groupId>org.apache.dubbo</groupId> <artifactId>dubbo-dependencies-zookeeper</artifactId> <type>pom</type> </dependency> <dependency> <groupId>org.projectlombok</groupId> <artifactId>lombok</artifactId> </dependency> <dependency> <groupId>org.apache.dubbo</groupId> <artifactId>dubbo-spring-boot-starter</artifactId> </dependency> </dependencies> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> <version>${springboot.version}</version> </plugin> </plugins> </build> </project>
- 编写配置文件<font color="blue">application.yml</font>,注意dubbo.registry.address的值:
dubbo: application: #application-name 本模块名字 name: springboot-zk-consumer registry: address: zookeeper://192.168.50.43:2181 server: port: 8081
- 编写调用远程服务的代码,如下,可见如果想调用远程服务,只要对接口做<font color="blue">@Reference</font>注释即可,另外还通过<font color="red">timeout</font>属性增加了超时配置:
package com.bolingcavalry.springbootzkconsumer.service; import com.bolingcavalry.dubbopractice.service.DemoService; import org.apache.dubbo.config.annotation.Reference; import org.springframework.stereotype.Service; @Service public class RemoteInvokeServiceImpl { @Reference(timeout = 2000) private DemoService demoService; public String sayHello(String name) { return "from dubbo remote (zk registry center mode) : " + demoService.sayHello(name); } }
- 再编写对外提供web服务的Controller类:
package com.bolingcavalry.springbootzkconsumer.controller; import com.bolingcavalry.springbootzkconsumer.service.RemoteInvokeServiceImpl; import io.swagger.annotations.Api; import io.swagger.annotations.ApiImplicitParam; import io.swagger.annotations.ApiOperation; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.web.bind.annotation.PathVariable; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RequestMethod; import org.springframework.web.bind.annotation.RestController; @RestController @RequestMapping("/demo") @Api(tags = {"DemoController"}) public class DemoController { @Autowired private RemoteInvokeServiceImpl remoteInvokeService; @ApiOperation(value = "获取dubbo service provider的响应", notes="\"获取dubbo service provider的响应") @ApiImplicitParam(name = "name", value = "昵称", paramType = "path", required = true, dataType = "String") @RequestMapping(value = "/{name}", method = RequestMethod.GET) public String sayHello(@PathVariable String name){ return remoteInvokeService.sayHello(name); } }
- 还要添加swagger配置类:
package com.bolingcavalry.springbootzkconsumer; import org.springframework.context.annotation.Bean; import org.springframework.context.annotation.Configuration; import springfox.documentation.builders.ApiInfoBuilder; import springfox.documentation.builders.PathSelectors; import springfox.documentation.builders.RequestHandlerSelectors; import springfox.documentation.service.ApiInfo; import springfox.documentation.service.Contact; import springfox.documentation.service.Tag; import springfox.documentation.spi.DocumentationType; import springfox.documentation.spring.web.plugins.Docket; import springfox.documentation.swagger2.annotations.EnableSwagger2; @Configuration @EnableSwagger2 public class SwaggerConfig { @Bean public Docket createRestApi() { return new Docket(DocumentationType.SWAGGER_2) .apiInfo(apiInfo()) .tags(new Tag("DemoController", "演示服务")) .select() // 当前包路径 .apis(RequestHandlerSelectors.basePackage("com.bolingcavalry.springbootzkconsumer.controller")) .paths(PathSelectors.any()) .build(); } //构建 api文档的详细信息函数,注意这里的注解引用的是哪个 private ApiInfo apiInfo() { return new ApiInfoBuilder() //页面标题 .title("dubbo远程调用服务的操作(zk注册中心)") //创建人 .contact(new Contact("程序员欣宸", "https://github.com/zq2599/blog_demos", "zq2599@gmail.com")) //版本号 .version("1.0") //描述 .description("API 描述") .build(); } }
- 最后是启动类<font color="blue">SpringBootZKConsumerApplication.java</font>:
package com.bolingcavalry.springbootzkconsumer; import org.apache.dubbo.config.spring.context.annotation.EnableDubbo; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; @SpringBootApplication @EnableDubbo public class SpringBootZKConsumerApplication { public static void main(String[] args) { SpringApplication.run(SpringBootZKConsumerApplication.class, args); } }
- 至此,服务消费方编码完成,直接在IDEA上运行<font color="blue">SpringBootZKConsumerApplication</font>类即可启动,如下图,可见服务消费方也连接Zookeeper成功:
8. 通过浏览器访问swagger,地址是:http://localhost:8081/swagger-ui.html ,如下图,点击红框位置展开接口详情:
- 如下图,输入web接口参数发起请求:
10. 下图红框中就是响应的数据,内容是<font color="blue">springbootzkconsumer</font>远程调用<font color="red">springbootzkprovider</font>的服务得到的:
查看Zookeeper上的数据
- 再回顾一下官方的有关Zookeeper注册中心中数据的描述,如下图:
- 按照上述信息,咱们去Zookeeper看看数据,验证和上图是否一致,登录Zookeeper后执行<font color="blue">zkCli.sh</font>进度交互模式;
- 查看根目录,果然有名为dubbo的子目录:
[zk: localhost:2181(CONNECTED) 18] ls / [dubbo, log_dir_event_notification, isr_change_notification, zookeeper, admin, consumers, cluster, config, latest_producer_id_block, controller, brokers, controller_epoch]
- 再看dubbo目录下,有远程服务的子目录:
[zk: localhost:2181(CONNECTED) 19] ls /dubbo [com.bolingcavalry.dubbopractice.service.DemoService, config, metadata]
- 查看远程服务的providers节点,果然有服务提供者的信息:
[zk: localhost:2181(CONNECTED) 16] get /dubbo/com.bolingcavalry.dubbopractice.service.DemoService/providers 169.254.38.208 cZxid = 0x552 ctime = Sat Oct 17 04:05:52 UTC 2020 mZxid = 0x552 mtime = Sat Oct 17 04:05:52 UTC 2020 pZxid = 0x5ec cversion = 27 dataVersion = 0 aclVersion = 0 ephemeralOwner = 0x0 dataLength = 14 numChildren = 1
- 再看看consumer节点的内容:
[zk: localhost:2181(CONNECTED) 17] get /dubbo/com.bolingcavalry.dubbopractice.service.DemoService/consumers 169.254.38.208 cZxid = 0x55f ctime = Sat Oct 17 04:22:58 UTC 2020 mZxid = 0x55f mtime = Sat Oct 17 04:22:58 UTC 2020 pZxid = 0x5f0 cversion = 33 dataVersion = 0 aclVersion = 0 ephemeralOwner = 0x0 dataLength = 14 numChildren = 1
- 可见Zookeeper上记录的数据与官方文档描述的一致;
- 至此,dubbo与springboot集成的实战就完成了,希望能给您提供一些参考,助您快速开发dubbo应用;