Dubbo、Spring、Zookeeper、集成基础案例(多版本兼容发布)

摘要：最近抽时间系统的学习了Dubbo的一些内容，趁有时间，整理下，顺便记录下，以防以后回顾。前面我们学校了Dubbo的参数回调，本次我们学习下Dubbo的多版本兼容发布、当一个接口实现、，出现不兼容升级时，可以用版本号过渡，版本号不同的服务相互间不引用。可以按照以下的步骤进行版本迁移：

1>.在低压力时间段，先升级一半提供者为新版本

2>.再将所有消费者升级为新版本

3>.然后将剩下的一半提供者升级为新版本

一：运行环境

1>:JDK 1.8

2>:IDEA 2018.1

3>:Zookeeper 3.x

4>:Maven 3.2

5>:Dubbo 2.8.4

二：项目结构

三：服务提供者、pom.xml和上一篇一样，这里就不再贴出来了

VersionService.java

package com.micai.dubbo.provider;

/**
 * @Auther: zhaoxinguo
 * @Date: 2018/9/13 17:44
 * @Description:
 */
public interface VersionService {

    String sayHello(String name);
}

VersionServiceImpl.java

package com.micai.dubbo.provider;

import com.alibaba.dubbo.config.annotation.Service;

/**
 * @Auther: zhaoxinguo
 * @Date: 2018/9/13 17:44
 * @Description:
 */
@Service(version = "1.0.0")
public class VersionServiceImpl implements VersionService {

    @Override
    public String sayHello(String name) {
        return "hello, " + name;
    }
}

VersionServiceImpl2.java

package com.micai.dubbo.provider;

import com.alibaba.dubbo.config.annotation.Service;

/**
 * @Auther: zhaoxinguo
 * @Date: 2018/9/13 17:45
 * @Description:
 */
@Service(version = "2.0.0")
public class VersionServiceImpl2 implements VersionService {

    @Override
    public String sayHello(String name) {
        return "hello2, " + name;
    }
}

Provider.java

package com.micai.dubbo;

import org.springframework.context.support.ClassPathXmlApplicationContext;

import java.io.IOException;

/**
 * @Auther: zhaoxinguo
 * @Date: 2018/9/10 14:13
 * @Description:
 */
public class Provider {

    public static void main(String [] args) {
        ClassPathXmlApplicationContext classPathXmlApplicationContext = new ClassPathXmlApplicationContext("applicationContext.xml");
        classPathXmlApplicationContext.start();
        try {
            System.in.read();//按任意键退出
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

Provider2.java

package com.micai.dubbo;

import org.springframework.context.support.ClassPathXmlApplicationContext;

import java.io.IOException;

/**
 * @Auther: zhaoxinguo
 * @Date: 2018/9/10 14:13
 * @Description:
 */
public class Provider2 {

    public static void main(String [] args) {
        ClassPathXmlApplicationContext classPathXmlApplicationContext = new ClassPathXmlApplicationContext("applicationContext2.xml");
        classPathXmlApplicationContext.start();
        try {
            System.in.read();//按任意键退出
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

applicationContext.xml

<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:dubbo="http://code.alibabatech.com/schema/dubbo"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
       http://www.springframework.org/schema/beans/spring-beans-4.2.xsd
       http://code.alibabatech.com/schema/dubbo
       http://code.alibabatech.com/schema/dubbo/dubbo.xsd">

    <!--提供方应用信息，用于计算依赖关系-->
    <dubbo:application name="version-provider"/>

    <!--使⽤zookeeper注册中⼼暴露服务地址-->
    <dubbo:registry address="zookeeper://127.0.0.1:2181"/>

    <!--用dubbo协议在20880端口暴露服务-->
    <dubbo:protocol name="dubbo" port="20880"/>

    <!--<!–声明需要暴露的服务接口–>
    <dubbo:service interface="com.micai.dubbo.provider.DemoService" ref="demoService"/>
    <!–和本地bean一样实现服务–>
    <bean id="demoService" class="com.micai.dubbo.provider.DemoServiceImpl"/>-->

    <!--扫描注解包路径，多个包⽤逗号分隔，不填pacakge表示扫描当前ApplicationContext中所有的类-->
    <dubbo:annotation package="com.micai.dubbo.provider"/>

</beans>

applicationContext2.xml

<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:dubbo="http://code.alibabatech.com/schema/dubbo"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
       http://www.springframework.org/schema/beans/spring-beans-4.2.xsd
       http://code.alibabatech.com/schema/dubbo
       http://code.alibabatech.com/schema/dubbo/dubbo.xsd">

    <!--提供方应用信息，用于计算依赖关系-->
    <dubbo:application name="version-provider2"/>

    <!--使⽤zookeeper注册中⼼暴露服务地址-->
    <dubbo:registry address="zookeeper://127.0.0.1:2181"/>

    <!--用dubbo协议在20882端口暴露服务-->
    <dubbo:protocol name="dubbo" port="20882"/>

    <!--<!–声明需要暴露的服务接口–>
    <dubbo:service interface="com.micai.dubbo.provider.DemoService" ref="demoService"/>
    <!–和本地bean一样实现服务–>
    <bean id="demoService" class="com.micai.dubbo.provider.DemoServiceImpl"/>-->

    <!--扫描注解包路径，多个包⽤逗号分隔，不填pacakge表示扫描当前ApplicationContext中所有的类-->
    <dubbo:annotation package="com.micai.dubbo.provider"/>

</beans>

四：服务消费者、pom.xml和上一篇一样，这里就不再贴出来了

VersionAction.java

package com.micai.dubbo.consumer;

import com.alibaba.dubbo.config.annotation.Reference;
import com.micai.dubbo.provider.VersionService;
import org.springframework.stereotype.Component;

/**
 * @Auther: zhaoxinguo
 * @Date: 2018/9/13 17:54
 * @Description:
 */
@Component
public class VersionAction {

    @Reference(version = "1.0.0")
    private VersionService versionService;

    @Reference(version = "2.0.0")
    private VersionService versionService2;

    public String sayHello() {
        String result = versionService.sayHello("world");
        return result;
    }

    public String sayHello2() {
        String result = versionService2.sayHello("world");
        return result;
    }

}

Consumer.java

package com.micai.dubbo;

import com.micai.dubbo.consumer.VersionAction;
import com.micai.dubbo.provider.VersionService;
import org.springframework.context.support.ClassPathXmlApplicationContext;

import java.io.IOException;

/**
 * @Auther: zhaoxinguo
 * @Date: 2018/9/11 14:36
 * @Description:
 */
public class Consumer {

    public static void main(String [] args) {
        try {
            ClassPathXmlApplicationContext classPathXmlApplicationContext = new ClassPathXmlApplicationContext("applicationContext.xml");
            classPathXmlApplicationContext.start();
            VersionAction versionAction = (VersionAction) classPathXmlApplicationContext.getBean("versionAction");
            String result = versionAction.sayHello();
            System.out.println("版本1调用返回结果：" + result);
            Thread.sleep(2000);
            String result2 = versionAction.sayHello2();
            System.out.println("版本2调用返回结果：" + result2);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }
}

applicationContext.xml

<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:dubbo="http://code.alibabatech.com/schema/dubbo"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
       http://www.springframework.org/schema/beans/spring-beans-4.2.xsd
       http://code.alibabatech.com/schema/dubbo
       http://code.alibabatech.com/schema/dubbo/dubbo.xsd">

    <!--消费方应用名、用于计算依赖关系，不是匹配条件，不要与提供方一样-->
    <dubbo:application name="version-consumer"/>

    <!--使用zookeeper注册中心暴露发现服务地址-->
    <dubbo:registry address="zookeeper://127.0.0.1:2181"/>

    <!--<!–生成远程服务代理，可以和本地bean一样使用demoService–>
    <dubbo:reference id="demoService" interface="com.micai.dubbo.provider.DemoService"/>-->

    <!--扫描注解包路径，多个包⽤逗号分隔，不填pacakge表示扫描当前ApplicationContext中所有的类-->
    <dubbo:annotation package="com.micai.dubbo.consumer"/>

</beans>

五：运行结果