微服务：dubbox+zookeeper构建restful风格

本章内容基于dubbo+zookeeper快速搭建
上一节，我们快速搭建了一个简单的dubbo服务（我姑且这样称呼）
弊端当然是，只有同样是java写的消费端才可以调用我们的服务。
所以搞个restful风格吧！！！

首先澄清dubbox的主人是当当网，而bubbo是阿里。而restful风格的支持也是在dubbox中才体现的。但是由于本人才浅，没有找到maven仓库中的dubbox。只能自己编译一下了。

dubbox-2.8.0 maven构建
1.下载源码包，这里我选择了2.8.0
https://github.com/dangdangdotcom/dubbox/releases
2.下载解压，开始install吧
跳过测试，比较快

mvn install -Dmaven.test.skip=true

这样本地仓库有了dubbox-2.8.0。我们就可以使用了。
注意SUCCESS后瞅瞅，本地仓库是否存在了哟！！！
开始我们的restful之旅
参见官方指导
使用restful，需要额外引入dubbo-rpc-rest

<dependency>
    <groupId>com.alibabagroupId>
    <artifactId>dubbo-rpc-restartifactId>
    <version>2.8.0version>
dependency>

1.服务接口

package com.xbz.learning.dubbox.demo.provider;

import com.xbz.learning.dubbox.demo.entity.User;

@Path("user")
@Produces({MediaType.APPLICATION_JSON, MediaType.TEXT_XML})
public interface DemoService {
    @GET
    @Path("{uid}")
    public User sayHello(@PathParam("uid")String userId);
}

2.服务实现类

package com.xbz.learning.dubbox.demo.provider.impl;

import javax.ws.rs.GET;
import javax.ws.rs.Path;
import javax.ws.rs.PathParam;
import javax.ws.rs.Produces;
import javax.ws.rs.core.MediaType;

import com.xbz.learning.dubbox.demo.entity.User;
import com.xbz.learning.dubbox.demo.provider.DemoService;
@Path("user")
@Produces({MediaType.APPLICATION_JSON, MediaType.TEXT_XML})
public class DemoServiceImpl implements DemoService{

    @GET
    @Path("{uid}")
    public User sayHello(@PathParam("uid")String userId) {
        System.out.println("input param uid :"+userId);
        User user=new User();
        user.setUsername("xbz");
        user.setPassword("1215xubin");
        return user;
    }

}

注意：
1.类的上方要写一个@Path注解，否则会报如下错误
2.注解会依据接口类的定义，官方说法是接口注解在实现类上面有利于代码维护
3.对于dubbo消费者必须要在提供的接口上体现注解，所以我这里接口类和实现类保持一致的注解

java.lang.RuntimeException: Class is not a root resource. It, or one of its interfaces must be annotated with @Path:[xxx类名]
3.暴漏服务

<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

    xmlns:p="http://www.springframework.org/schema/p"
    xmlns:c="http://www.springframework.org/schema/c"

    xmlns:context="http://www.springframework.org/schema/context"
    xmlns:aop="http://www.springframework.org/schema/aop"
    xmlns:mvc="http://www.springframework.org/schema/mvc"
    xmlns:dubbo="http://code.alibabatech.com/schema/dubbo"

    xsi:schemaLocation=
        "http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans.xsd 

        http://www.springframework.org/schema/context
        http://www.springframework.org/schema/context/spring-context.xsd

        http://www.springframework.org/schema/aop
        http://www.springframework.org/schema/aop/spring-aop.xsd

        http://www.springframework.org/schema/mvc
        http://www.springframework.org/schema/mvc/spring-mvc.xsd

        http://code.alibabatech.com/schema/dubbo
        http://code.alibabatech.com/schema/dubbo/dubbo.xsd
">

    
    <dubbo:application name="hello-world-app"  />

    
    <dubbo:registry address="zookeeper://192.168.35.100:2181" check="false" subscribe="false" />

    
    <dubbo:service version="1.0.0" interface="com.xbz.learning.dubbox.demo.provider.DemoService" ref="demoService" />

    
    <dubbo:protocol name="rest" port="8080" server="jetty" >dubbo:protocol>
    
    <bean id="demoService" class="com.xbz.learning.dubbox.demo.provider.impl.DemoServiceImpl">bean>

beans>

4.启动类

package com.xbz.learning.dubbox.demo;

import java.io.IOException;

import org.junit.Test;
import org.springframework.context.support.ClassPathXmlApplicationContext;

import com.xbz.learning.dubbox.demo.provider.DemoService;

public class DemoServiceRegisterTest {
    @Test
    public void startDemoProvider() throws IOException{
        System.out.println("准备启动DemoServiceProvider");
        ClassPathXmlApplicationContext ap=new ClassPathXmlApplicationContext("classpath:applicationContext-provider.xml");
        DemoService demoServiceProvider=(DemoService) ap.getBean("demoService");
        System.out.println("启动DemoServiceProvider完成");
        System.in.read();
    }
}

启动完成后，在浏览器中访问：
http://127.0.0.1:8080/user/888
看看效果

---

客户端访问方式
1.dubbo消费者–>dubbox提供者
2.非dubbo消费者–>使用restful请求
非dubbo（x）客户端当然可以使用restful请求数据喽，选择自己喜欢的方式就好

dubbo消费者如果调用rest 的dubbox服务呢？
就像消费者根本不知道rest这回事一般，写写配置文件

<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

    xmlns:p="http://www.springframework.org/schema/p"
    xmlns:c="http://www.springframework.org/schema/c"

    xmlns:context="http://www.springframework.org/schema/context"
    xmlns:aop="http://www.springframework.org/schema/aop"
    xmlns:mvc="http://www.springframework.org/schema/mvc"
    xmlns:dubbo="http://code.alibabatech.com/schema/dubbo"

    xsi:schemaLocation=
        "http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans.xsd 

        http://www.springframework.org/schema/context
        http://www.springframework.org/schema/context/spring-context.xsd

        http://www.springframework.org/schema/aop
        http://www.springframework.org/schema/aop/spring-aop.xsd

        http://www.springframework.org/schema/mvc
        http://www.springframework.org/schema/mvc/spring-mvc.xsd

        http://code.alibabatech.com/schema/dubbo
        http://code.alibabatech.com/schema/dubbo/dubbo.xsd
">

    
    <dubbo:application name="consumer-of-helloworld-app"  />

    
    <dubbo:registry address="zookeeper://192.168.35.100:2181" />

    
    <dubbo:reference 
                id="demoService" 
                version="1.0.0" 
                interface="com.xbz.learning.dubbox.demo.provider.DemoService" 
    />

beans>

的确和上一节的调用方式，一模一样吧！！！