版本描述:dubbo 2.7.2
Dubbo是阿里开源的一款RPC框架,最近在学习微服务的时候有提及到。因此对Dubbo进行了入门级体验,这里主要体验体验Dubbo的几种配置方式,如XML配置、API配置、注解配置,以及Springboot里整合Dubbo,同时体验几种注册中心,如simple、zk、redis、multicast。
Dubbo官网内容还是很丰富的,支持中文。地址:http://dubbo.apache.org/zh-cn/docs/user/quick-start.html
1 Dubbo配置使用
1.1 基于原生API的配置
官网文档:http://dubbo.apache.org/zh-cn/docs/user/configuration/api.html
怎么说呢,参考官网这个文档实现时踩了不少坑,因为官网提供的注册中心没法使用,又是初次接触,走了不少弯路,而自己又是直肠子一根,非要自己实现一个注册中心,然后参考官网给的Simple注册中心的例子,有两点逼得我强迫症犯了,首先使用的是XML配置的方式创建注册中心服务,而我这里只想通过原生API实现,另一个
<!-- 简单注册中心实现,可自行扩展实现集群和状态同步 -->
<bean id="registryService" class="org.apache.dubbo.registry.simple.SimpleRegistryService" />
这里面提到的org.apache.dubbo.registry.simple.SimpleRegistryService这个类,我死活找不到。就这俩问题纠结了一天。后来终于解决了,在github上dubbo源码的测试文件里找到了。心里一万匹cnm在奔腾。回归正题,使用原生API的方式配置其实就是自己创建实例,传入配置参数,启动服务。下面将一步步讲解。
1.1.1 项目准备
首先创建一个名为dubbo-demo-api的模块,然后再该模块下创建三个子模块
dubbo-demo-api/
├── dubbo-demo-api-api
├── dubbo-demo-api-consumer
├── dubbo-demo-api-provider
└── pom.xml
- dubbo-demo-api-api:提供演示接口
- dubbo-demo-api-consumer:服务消费者
- dubbo-demo-api-provider:服务提供者
1.1.2 dubbo-demo-api-api 模块
该模块主要提供用来演示的接口,在learn.demo.dubbo.api.api包下创建DemoService接口,如下所示
package learn.demo.dubbo.api.api;
/**
* Created by shirukai on 2019-06-20 09:23
* DemoService 接口
*/
public interface DemoService {
String sayHello(String name);
}
1.1.3 dubbo-demo-api-provider模块
该模块是创建dubbo提供者服务。首先要引入dubbo相关依赖
<!-- dubbo -->
<dependency>
<groupId>org.apache.dubbo</groupId>
<artifactId>dubbo</artifactId>
<version>2.7.2</version>
</dependency>
然后引入api模块
<dependency>
<groupId>learn.demo</groupId>
<artifactId>dubbo-demo-api-api</artifactId>
<version>1.0</version>
<scope>compile</scope>
</dependency>
1.1.3.1 实现DemoService接口
上面我们在api模块中定义的DemoService接口,这里我们在learn.demo.dubbo.api.provider这个包下实现该接口。创建名为DemoServiceImpl的类,内容如下:
package learn.demo.dubbo.api.provider;
import learn.demo.dubbo.api.api.DemoService;
/**
* Created by shirukai on 2019-06-20 09:25
* DemoService接口实现
*/
public class DemoServiceImpl implements DemoService {
@Override
public String sayHello(String name) {
return "This service base in API.\nHello " + name;
}
}
1.1.3.2 实现Simple注册中心
这里在实现Provider之前,先实现以下Simple注册中心,之前也有讲到官网在讲Simple注册中心的时候,是使用Spring的XML配置去生成Bean然后创建服务的,而且里面的提到的SimpleRegistryService类也找不到,经过九九八十一难这里使用API去实现一个Simple注册中心。这里需要几个类:AbstractRegistryService,SimpleRegistryExporter,SimpleRegistryService。这几个类可以从dubbo的github上找到,https://github.com/apache/dubbo/tree/master/dubbo-registry/dubbo-registry-default/src/test/java/org/apache/dubbo/registry/dubbo。
我们可以在自己的项目里,创建 org.apache.dubbo.registry包,然后将这三个类复制进去。
在learn.demo.dubbo.api.provider包下创建SimpleRegistryServiceProvider类用来提供注册中心服务,代码如下:
package learn.demo.dubbo.api.provider;
import org.apache.dubbo.registry.SimpleRegistryExporter;
/**
* Created by shirukai on 2019-06-20 09:32
* <p>
* 简单注册中心服务提供者
* 基于RegistryService接口实现的简单注册中心
* 代码位置:
* https://github.com/apache/dubbo/tree/master/dubbo-registry/dubbo-registry-default/src/test/java/org/apache/dubbo/registry/dubbo
*/
public class SimpleRegistryServiceProvider {
public static void main(String[] args) throws Exception {
// 暴露注册中心服务,端口为9090
SimpleRegistryExporter.export(9090);
// 任意输入退出
System.in.read();
}
}
1.1.3.3 实现DemoServiceProvider
使用Dubbo的原生API实现生产者,大体流程:
- 创建应用配置ApplicationConfig,我们可以设置应用名称、设置qos端口等等。
- 创建注册中心配置RegistryConfig,可以设置注册中心类型,地址,端口,用户名,密码等。
- 创建服务配置ServiceConfig,此实例很重要,有与注册中心的连接
- 暴露服务export
内容如下:
package learn.demo.dubbo.api.provider;
import learn.demo.dubbo.api.api.DemoService;
import org.apache.dubbo.config.ApplicationConfig;
import org.apache.dubbo.config.RegistryConfig;
import org.apache.dubbo.config.ServiceConfig;
/**
* Created by shirukai on 2019-06-20 09:30
* <p>
* DemoService 生产者
* 该Demo注册中心使用自定义注册中心,SimpleRegistryService
* 所以在启动该服务之前,需要先启动注册中心
*/
public class DemoServiceProvider {
public static void main(String[] args) throws Exception {
// 应用配置
ApplicationConfig applicationConfig = new ApplicationConfig("api-demo-service-provider");
// qos 默认端口22222在本地同时启动多个服务时,需要手动修改
applicationConfig.setQosPort(22222);
// 注册中心配置
RegistryConfig registryConfig = new RegistryConfig("127.0.0.0:9090");
// 服务配置,此实例很重,封装了与注册中心的连接,请自行缓存,否则可能造成内存和连接泄漏
ServiceConfig<DemoService> service = new ServiceConfig<>();
service.setApplication(applicationConfig);
service.setRegistry(registryConfig);
service.setInterface(DemoService.class);
service.setRef(new DemoServiceImpl());
// 暴露服务
service.export();
// 输入任意退出
System.in.read();
}
}
1.1.4 dubbo-demo-api-consumer模块
该模块dubbo服务消费者,依然需要引入dubbo和自定义api的jar包。
<!-- dubbo -->
<dependency>
<groupId>org.apache.dubbo</groupId>
<artifactId>dubbo</artifactId>
<version>2.7.2</version>
</dependency>
<dependency>
<groupId>learn.demo</groupId>
<artifactId>dubbo-demo-api-api</artifactId>
<version>1.0</version>
<scope>compile</scope>
</dependency>
consumer的实现与provider步骤类似
- 创建应用配置ApplicationConfig
- 创建配置中心配置RegistryConfig
- 创建服务ReferenceConfig
- 获取接口实例
代码如下:
package learn.demo.api.consumer;
import learn.demo.dubbo.api.api.DemoService;
import org.apache.dubbo.config.ApplicationConfig;
import org.apache.dubbo.config.ReferenceConfig;
import org.apache.dubbo.config.RegistryConfig;
/**
* Created by shirukai on 2019-06-20 09:53
* DemoService 消费者
*/
public class DemoServiceConsumer {
public static void main(String[] args) {
// 应用配置
ApplicationConfig applicationConfig = new ApplicationConfig("dubbo-demo-api-consumer");
applicationConfig.setQosPort(22223);
// 配置注册中心
RegistryConfig registryConfig = new RegistryConfig("127.0.0.1:9090");
ReferenceConfig<DemoService> reference = new ReferenceConfig<>();
reference.setApplication(applicationConfig);
reference.setRegistry(registryConfig);
reference.setInterface(DemoService.class);
// 获取服务
DemoService service = reference.get();
// 服务调用
String message = service.sayHello("dubbo !");
System.out.println(message);
}
}
1.2 基于XML的配置
上面我们介绍了使用API进行Dubbo的配置,该中方式方便集成其它系统,但是实现繁琐。所以官方提供了Spring基于XML的配置方式,该配置方式依赖于Spring,是加载Bean的方式创建服务。官网文档:http://dubbo.apache.org/zh-cn/docs/user/configuration/xml.html
1.2.1 项目准备
首先创建一个名为dubbo-demo-xml的模块,然后再该模块下创建三个子模块
dubbo-demo-xml/
├── dubbo-demo-xml-api
├── dubbo-demo-xml-consumer
├── dubbo-demo-xml-provider
└── pom.xml
- dubbo-demo-xml-api:提供演示接口
- dubbo-demo-xml-consumer:服务消费者
- dubbo-demo-xml-provider:服务提供者
1.2.2 dubbo-demo-xml-api模块
与dubbo-demo-api-api相同。
1.2.3 dubbo-demo-xml-provider模块
同上引入api以及dubbo依赖。
1.2.3.1 DemoServiceImpl
实现定义的api接口。
package learn.demo.dubbo.xml.provider;
import learn.demo.dubbo.xml.api.DemoService;
/**
* Created by shirukai on 2019-06-20 10:19
* 实验DemoService接口
*/
public class DemoServiceImpl implements DemoService {
@Override
public String sayHello(String name) {
return "This service base in XML.\nHello " + name;
}
}
1.2.3.2 dubbo-provider.xml
在resource/spring下创建dubbo-provider.xml配置文件,用来配置dubbo的provider服务。具体参数参考官网。
<beans xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:dubbo="http://dubbo.apache.org/schema/dubbo"
xmlns="http://www.springframework.org/schema/beans"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.3.xsd
http://dubbo.apache.org/schema/dubbo http://dubbo.apache.org/schema/dubbo/dubbo.xsd">
<!-- provider's application name, used for tracing dependency relationship -->
<dubbo:application name="demo-xml-provider">
<!-- 指定qos端口,配置优先级低于dubbo.properties-->
<dubbo:parameter key="qos.port" value="22222"/>
</dubbo:application>
<!-- 基于广播的注册中心 -->
<dubbo:registry address="multicast://224.5.6.7:1234"/>
<!-- use dubbo protocol to export service on port 20880 -->
<dubbo:protocol name="dubbo"/>
<!-- service implementation, as same as regular local bean -->
<bean id="demoService" class="learn.demo.dubbo.xml.provider.DemoServiceImpl"/>
<!-- declare the service interface to be exported -->
<dubbo:service interface="learn.demo.dubbo.xml.api.DemoService" ref="demoService"/>
</beans>
1.2.3.3 DemoServiceProvider
Provider实现比较简单,使用ClassPathXmlApplicationContext从xml获取应用上下文,然后启动。
package learn.demo.dubbo.xml.provider;
import org.springframework.context.support.ClassPathXmlApplicationContext;
/**
* Created by shirukai on 2019-06-20 10:18
* 基于XML的Dubbo服务提供者
*/
public class DemoServiceProvider {
public static void main(String[] args) throws Exception {
// 从XML配置文件中获取应用上下文
ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext("spring/dubbo-provider.xml");
context.start();
System.in.read();
}
}
1.2.4 dubbo-demo-xml-consumer模块
同上需在pom中引入api和dubbo依赖。
1.2.4.1 dubbo-consumer.xml
使用xml配置consumer服务。在resource/spring下创建dubbo-consumer.xml,内容如下
<beans xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:dubbo="http://dubbo.apache.org/schema/dubbo"
xmlns="http://www.springframework.org/schema/beans"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.3.xsd
http://dubbo.apache.org/schema/dubbo http://dubbo.apache.org/schema/dubbo/dubbo.xsd">
<dubbo:application name="demo-xml-consumer"/>
<!-- 使用广播注册中心 -->
<dubbo:registry address="multicast://224.5.6.7:1234"/>
<!-- generate proxy for the remote service, then demoService can be used in the same way as the
local regular interface -->
<dubbo:reference id="demoService" check="false" interface="learn.demo.dubbo.xml.api.DemoService"/>
</beans>
1.2.4.2 DemoServiceConsumer
使用ClassPathXmlApplicationContext获取应用上下文,并在上下文中获取DemoService接口对应的Bean,然后调用接口方法。
package learn.demo.dubbo.xml.consumer;
import learn.demo.dubbo.xml.api.DemoService;
import org.springframework.context.support.ClassPathXmlApplicationContext;
/**
* Created by shirukai on 2019-06-20 11:07
* 基于XML的Dubbo服务消费之
*/
public class DemoServiceConsumer {
public static void main(String[] args){
ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext("spring/dubbo-consumer.xml");
context.start();
DemoService demoService = context.getBean("demoService", DemoService.class);
String message = demoService.sayHello("world");
System.out.println(message);
}
}
1.2.4.3 补充,关于dubbo的配置
dubbo的配置,我们可以通过dubbo.properties文件来配置,如我要修改qos端口,可以只创建dubbo.properites文件,然后添加如下配置:
# dubbo相关配置文件
dubbo.application.qos.port=22223
1.3 基于注解的配置
官网:http://dubbo.apache.org/zh-cn/docs/user/configuration/annotation.html
dubbo关于注解的配置,与xml如出一辙,只不过我们不需要配置xml了,在需要暴露的接口实现类上添加@Service注解,然后通过@Configuration将相关配置注入到Spring里。
1.3.1 项目准备
首先创建一个名为dubbo-demo-xml的模块,然后再该模块下创建三个子模块
dubbo-demo-annotation/
├── dubbo-demo-annotation-api
├── dubbo-demo-annotation-consumer
├── dubbo-demo-annotation-provider
└── pom.xml
- dubbo-demo-annotation-api:提供演示接口
- dubbo-demo-annotation-consumer:服务消费者
- dubbo-demo-annotation-provider:服务提供者
1.3.2 dubbo-demo-annotation-api模块
跟dubbo-demo-api-api模块相同。
1.3.3 dubbo-demo-annotation-provider模块
1.3.3.1 DemoServiceImpl
同上,实现DemoService接口,但是需要使用@Service来标记该实现类要通过Provider暴露服务。
package learn.demo.dubbo.annotation.provider;
import lear.demo.dubbo.annotation.api.DemoService;
import org.apache.dubbo.config.annotation.Service;
/**
* Created by shirukai on 2019-06-20 14:04
* DemoService实现类
*/
@Service
public class DemoServiceImpl implements DemoService {
@Override
public String sayHello(String name) {
return "The service base in Annotation.\nHello" + name;
}
}
1.3.3.2 dubbo-provider.properties
通过dubbo-provider.properties来对dubbo的provider进行相应的配置。在resource/spring下创建dubbo-provider.properties文件,内容如下
dubbo.application.name=dubbo-demo-annotation-provider
dubbo.application.qos.port=22222
dubbo.protocol.name=dubbo
dubbo.protocol.port=20880
1.3.3.3 DemoServiceProvider
与xml配置相同,需要获取应用上下文,只不过使用AnnotationConfigApplicationContext来获取,并且需要将dubbo的配置通过@Configuration形式注入到Spring,并制定需要扫面的包路径,以及配置文件所在路径。内容如下:
package learn.demo.dubbo.annotation.provider;
import org.apache.dubbo.config.RegistryConfig;
import org.apache.dubbo.config.spring.context.annotation.EnableDubbo;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.PropertySource;
/**
* Created by shirukai on 2019-06-20 14:06
* DemoService提供者
*/
public class DemoServiceProvider {
public static void main(String[] args) throws Exception {
AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext(ProviderConfiguration.class);
context.start();
System.in.read();
}
@Configuration
@EnableDubbo(scanBasePackages = "learn.demo.dubbo.annotation.provider")
@PropertySource("classpath:/spring/dubbo-provider.properties")
static class ProviderConfiguration {
@Bean
public RegistryConfig registryConfig() {
RegistryConfig registryConfig = new RegistryConfig();
registryConfig.setAddress("multicast://224.5.6.7:1234");
return registryConfig;
}
}
}
1.3.4 dubbo-demo-annotation-consumer模块
1.3.4.1 dubbo-consumer.properties
通过dubbo-consumer.properties来配置dubbo的consumer的相关配置,如服务名称、注册中心地址等
dubbo.application.name=dubbo-demo-annotation-consumer
dubbo.registry.address=multicast://224.5.6.7:1234
1.3.4.2 DemoServiceComponent
通过@Component创建DemoService组件,并通过@Reference注入远程Dubbo提供的接口实例。
package learn.demo.dubbo.annotation.consumer.comp;
import lear.demo.dubbo.annotation.api.DemoService;
import org.apache.dubbo.config.annotation.Reference;
import org.springframework.stereotype.Component;
/**
* Created by shirukai on 2019-06-20 14:22
* DemoService 组件
*/
@Component("demoServiceComponent")
public class DemoServiceComponent implements DemoService {
@Reference
private DemoService demoService;
@Override
public String sayHello(String name) {
return demoService.sayHello(name);
}
}
1.3.4.3 DemoServiceConsumer
通过@Configuration注入dubbo相关配置,并通过AnnotationConfigApplicationContext获取应用上下文。
package learn.demo.dubbo.annotation.consumer;
import lear.demo.dubbo.annotation.api.DemoService;
import learn.demo.dubbo.annotation.consumer.comp.DemoServiceComponent;
import org.apache.dubbo.config.spring.context.annotation.EnableDubbo;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.PropertySource;
/**
* Created by shirukai on 2019-06-20 14:10
* DemoService消费者
*/
public class DemoServiceConsumer {
public static void main(String[] args) {
AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext(ConsumerConfiguration.class);
context.start();
DemoService service = context.getBean("demoServiceComponent", DemoServiceComponent.class);
String message = service.sayHello("world");
System.out.println(message);
}
@Configuration
@EnableDubbo(scanBasePackages = "learn.demo.dubbo.annotation.consumer.comp")
@PropertySource("classpath:/spring/dubbo-consumer.properties")
@ComponentScan(value = {"learn.demo.dubbo.annotation.consumer.comp"})
static class ConsumerConfiguration {
}
}
2 SpringBoot整合Dubbo
SpringBoot整合Dubbo简洁的不能再简洁,不需要额外的配置,只需要引入几个依赖包即可。
2.1 项目准备
首先创建一个名为dubbo-demo-springboot的模块,然后再该模块下创建三个子模块
dubbo-demo-springboot/
├── dubbo-demo-springboot-api
├── dubbo-demo-springboot-consumer
├── dubbo-demo-springboot-provider
└── pom.xml
- dubbo-demo-springboot-api:提供演示接口
- dubbo-demo-springboot-consumer:服务消费者
- dubbo-demo-springboot-provider:服务提供者
2.2 dubbo-demo-springboot-api模块
与之前api模块一样,定义DemoService接口。
2.3 dubbo-demo-springboot-provide模块
2.3.1 引入依赖
因为此项目是springboot项目,这里将springboot模块添加到parent
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.0.0.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
引入springboot starter
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter</artifactId>
</dependency>
引入dubbo springboot starter
<!-- Dubbo Spring Boot Starter -->
<dependency>
<groupId>org.apache.dubbo</groupId>
<artifactId>dubbo-spring-boot-starter</artifactId>
<version>2.7.1</version>
</dependency>
引入dubbo依赖
<dependency>
<groupId>org.apache.dubbo</groupId>
<artifactId>dubbo</artifactId>
<version>2.7.2</version>
</dependency>
引入api依赖
<dependency>
<groupId>org.apache.dubbo</groupId>
<artifactId>dubbo</artifactId>
<version>2.7.2</version>
</dependency>
2.3.2 application.properties
在resource创建application.properties配置文件,里面添加dubbo相应配置
spring.application.name=dubbo-spring-boot-provider
# dubbo
dubbo.scan.base-packages=learn.demo.dubbo.springboot.provider
dubbo.protocol.name=dubbo
dubbo.protocol.port=12345
dubbo.registry.address=multicast://224.5.6.7:1234
2.3.3 DemoServiceImpl
实现DemoService接口,并使用dubbo的@Service注解标记此类为dubbo暴露的服务实例
package learn.demo.dubbo.springboot.provider;
import learn.demo.dubbo.springboot.api.DemoService;
import org.apache.dubbo.config.annotation.Service;
/**
* Created by shirukai on 2019-06-20 15:08
*/
@Service(version = "1.0.0")
public class DemoServiceImpl implements DemoService {
@Override
public String sayHello(String name) {
return "The service of dubbo from springboot.\nHello " + name;
}
}
2.3.4 DemoServiceProvider
Dubbo 服务提供实现,主要启动SpringBoot即可。
package learn.demo.dubbo.springboot.provider;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
/**
* Created by shirukai on 2019-06-20 15:08
*/
@SpringBootApplication
public class DemoServiceProvider {
public static void main(String[] args) {
SpringApplication.run(DemoServiceProvider.class, args);
}
}
2.4 dubbo-demo-springboot-consumer模块
2.3.1 引入依赖
与provider一样,引入springboot-starter、dubbo-spring-boot-starter、dubbo、api依赖。另外这里提供了一个REST接口,所以需要引入web服务相关的依赖
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
2.3.2 application.properties
spring.application.name=dubbo-spring-boot-consumer
# dubbo
dubbo.scan.base-packages=learn.demo.dubbo.springboot.consumer
dubbo.registry.address=multicast://224.5.6.7:1234
2.3.4 DemoController
提供一个REST接口,并调用RPC服务
package learn.demo.dubbo.springboot.consumer.controller;
import learn.demo.dubbo.springboot.api.DemoService;
import org.apache.dubbo.config.annotation.Reference;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;
/**
* Created by shirukai on 2019-06-20 16:03
*/
@RestController
public class DemoController {
@Reference(version = "1.0.0")
private DemoService demoService;
@GetMapping(value = "/sayHello")
public String sayHello(@RequestParam("name") String name) {
return demoService.sayHello(name);
}
}
2.3.5 DemoServiceConsumer
Dubbo Consumser服务启动,,正常启动SpringBoot即可。
package learn.demo.dubbo.springboot.consumer;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
/**
* Created by shirukai on 2019-06-20 16:00
*/
@SpringBootApplication
public class DemoServiceConsumer {
public static void main(String[] args) {
SpringApplication.run(DemoServiceConsumer.class, args);
}
}