分布式服務(wù)開(kāi)發(fā)(4) Dubbo + Zookeeper

dubbo是一個(gè)分布式服務(wù)框架,是阿里巴巴SOA服務(wù)化治理方案的核心框架。zookeeper是一個(gè)為分布式應(yīng)用提供一致性服務(wù)的軟件,提供的功能包括:配置維護(hù)、域名服務(wù)、分布式同步、組服務(wù)等。zookeeper可以作為dubbo服務(wù)的注冊(cè)中心,兩者結(jié)合起來(lái)可以實(shí)現(xiàn)微服務(wù)中的 服務(wù)注冊(cè)、發(fā)現(xiàn)、負(fù)載均衡和健康檢查,容錯(cuò),動(dòng)態(tài)配置管理的功能。我們先用springMVC將dubbo服務(wù)暴露成瀏覽器可訪問(wèn)的http接口。

本例代碼已經(jīng)上傳到GitHub,傳送門(mén)見(jiàn)下:
https://github.com/ArchitectRoad/BoliERP.git

重要的事情說(shuō)前面。先總結(jié)Dubbo+Spring Boot使用過(guò)程中的要點(diǎn)、注意點(diǎn)吧。

  • Spring Boot的目的之一就是使開(kāi)發(fā)人員可以擺脫繁雜的xml配置,所以Spring Boot整合Dubbo時(shí),使用Annotation是推薦方式。使用Annotation集成Spring Boot + Dubbo時(shí)可以參照 https://github.com/JeffLi1993/springboot-learning-example。
  • 為便于更好理解Dubbo的原理,在本例中仍然使用xml進(jìn)行Dobbo provider和consumer的配置。Spring Boot + Dubbo聯(lián)合使用時(shí),需要顯示在入口類(lèi)中通過(guò)以下方式引用dubbo配置。
@ImportResource(classpath: dubbo-consumer.xml)
public class ProdWebApplication {
    ...
}
  • Service Provider打包為Jar,使用com.alibaba.dubbo.container.Main作為入口啟動(dòng)Spring容器時(shí),默認(rèn)讀取classpath:META-INF/spring/目錄下的applicationContext.xml。關(guān)于如何生成Service Provider Jar,詳見(jiàn)prodService模塊的pom.xml中的build節(jié)點(diǎn)定義。
  • 解決Dubbo與Spring Boot的依賴包沖突,引入dubbo時(shí)exclude spring。
           <dependency>
                <groupId>com.alibaba</groupId>
                <artifactId>dubbo</artifactId>
                <version>${dubbo-version}</version>
                <exclusions>
                    <exclusion>
                        <artifactId>spring</artifactId>
                        <groupId>org.springframework</groupId>
                    </exclusion>
                </exclusions>
            </dependency>
  • 解決log4j與slf4j的版本沖突。Exclude zookeeper中的slf4j與log4j,exclude zkclient中的log4j。
           <dependency>
                <groupId>org.apache.zookeeper</groupId>
                <artifactId>zookeeper</artifactId>
                <version>${zookeeper-version}</version>
                <!-- Solve conflict with Spring boot -->
                <exclusions>
                    <exclusion>
                        <groupId>org.slf4j</groupId>
                        <artifactId>slf4j-log4j12</artifactId>
                    </exclusion>
                    <exclusion>
                        <groupId>org.slf4j</groupId>
                        <artifactId>slf4j-api</artifactId>
                    </exclusion>
                    <exclusion>
                        <groupId>log4j</groupId>
                        <artifactId>log4j</artifactId>
                    </exclusion>
                </exclusions>
            </dependency>
            <dependency>
                <groupId>com.github.sgroschupf</groupId>
                <artifactId>zkclient</artifactId>
                <version>${zkclient-version}</version>
                <exclusions>
                    <exclusion>
                        <groupId>log4j</groupId>
                        <artifactId>log4j</artifactId>
                    </exclusion>
                </exclusions>
            </dependency>
  • classpath 和 classpath* 區(qū)別:
classpath: 只會(huì)到你的class路徑中查找找文件。只加載找到的第一個(gè)文件。
classpath*: 不僅包含class路徑,還包括jar文件中(class路徑)進(jìn)行查找。從多個(gè)jar文件中加載相同的文件。
用classpath*:需要遍歷所有的classpath,所以加載速度較慢。因此,在規(guī)劃的時(shí)候,應(yīng)該盡可能規(guī)劃好資源文件所在的路徑,盡量避免使用classpath*。
**/ 表示的是任意目錄。

項(xiàng)目結(jié)構(gòu)如下:

prodParentPom工程目錄
  • pordParentPom module
    定義所有模塊的parent pom,統(tǒng)一管理依賴版本。繼承spring-boot-starter-parent,并定義dubbo, zookeeper, zkclient版本。通過(guò)exclusion解決jar包沖突。
pom.xml
<?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">
    <modelVersion>4.0.0</modelVersion>
    <groupId>com.boli</groupId>
    <artifactId>prodParentPom</artifactId>
    <version>1.0-SNAPSHOT</version>
    <packaging>pom</packaging>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.5.2.RELEASE</version>
    </parent>

    <modules>
        <module>../prodApi</module>
        <module>../prodService</module>
        <module>../prodWebApp</module>
    </modules>

    <properties>
        <dubbo-version>2.5.3</dubbo-version>
        <zookeeper-version>3.4.9</zookeeper-version>
        <zkclient-version>0.1</zkclient-version>
    </properties>

    <dependencyManagement>
        <dependencies>
            <!-- dubbo dependency -->
            <dependency>
                <groupId>com.alibaba</groupId>
                <artifactId>dubbo</artifactId>
                <version>${dubbo-version}</version>
                <exclusions>
                    <exclusion>
                        <artifactId>spring</artifactId>
                        <groupId>org.springframework</groupId>
                    </exclusion>
                </exclusions>
            </dependency>
            <dependency>
                <groupId>org.apache.zookeeper</groupId>
                <artifactId>zookeeper</artifactId>
                <version>${zookeeper-version}</version>
                <!-- Solve conflict with Spring boot -->
                <exclusions>
                    <exclusion>
                        <groupId>org.slf4j</groupId>
                        <artifactId>slf4j-log4j12</artifactId>
                    </exclusion>
                    <exclusion>
                        <groupId>org.slf4j</groupId>
                        <artifactId>slf4j-api</artifactId>
                    </exclusion>
                    <exclusion>
                        <groupId>log4j</groupId>
                        <artifactId>log4j</artifactId>
                    </exclusion>
                </exclusions>
            </dependency>
            <dependency>
                <groupId>com.github.sgroschupf</groupId>
                <artifactId>zkclient</artifactId>
                <version>${zkclient-version}</version>
                <exclusions>
                    <exclusion>
                        <groupId>log4j</groupId>
                        <artifactId>log4j</artifactId>
                    </exclusion>
                </exclusions>
            </dependency>
        </dependencies>
    </dependencyManagement>
</project>
  • prodApi module
    Api接口定義,以及Dubbo consumer定義。prodService模塊具體實(shí)現(xiàn)Api接口。prodWebApp模塊引用該模塊,根據(jù)Api接口定義,通過(guò)zookeeper發(fā)現(xiàn)并調(diào)用具體服務(wù)。


    prodApi工程目錄
IProdSvc.java
/*
* Copyright (c) 2017 architectroad@yeah.net. All Rights Reserved.
*/
package com.boli.service.intfc.prod;

import java.util.List;

/**
 * Product Service Interface
 * Author: Joey Zhu (architectroad@yeah.net)
 * Date: 2017/3/11.
 * Time: 11:01
 */
public interface IProdSvc {
    public List<String> getProdList();

    public String sayHello (String name);
}

prodApi.consumer.xml
<?xml version="1.0" encoding="UTF-8"?>
<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.xsd http://code.alibabatech.com/schema/dubbo http://code.alibabatech.com/schema/dubbo/dubbo.xsd">

    <!-- 消費(fèi)者應(yīng)用信息,用于提供依賴關(guān)系 -->
    <dubbo:application name="prodSvcConsumer" />
    <!-- 注冊(cè)地址,用于消費(fèi)者尋找服務(wù),, 此處可以配置多個(gè)zookeeper -->
    <dubbo:registry protocol="zookeeper" address="127.0.0.1:2181" />
    <!-- 超時(shí)設(shè)置 -->
    <dubbo:consumer timeout="5000" />

    <!-- 引用的服務(wù) -->
    <dubbo:reference id="prodService" interface="com.boli.service.intfc.prod.IProdSvc" version="1.0.0" />

</beans>
pom.xml
<?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>prodParentPom</artifactId>
        <groupId>com.boli</groupId>
        <version>1.0-SNAPSHOT</version>
    </parent>

    <modelVersion>4.0.0</modelVersion>
    <groupId>com.boli</groupId>
    <artifactId>prodApi</artifactId>
    <version>1.0-SNAPSHOT</version>
    <packaging>jar</packaging>

    <dependencies>
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>dubbo</artifactId>
        </dependency>

        <dependency>
            <groupId>com.github.sgroschupf</groupId>
            <artifactId>zkclient</artifactId>
        </dependency>
    </dependencies>

</project>
  • prodService module
prodService工程目錄
ProdSvcProvider.java

Service Provider入口類(lèi)

/*
* Copyright (c) 2017 architectroad@yeah.net. All Rights Reserved.
*/
package com.boli;

import org.springframework.context.support.ClassPathXmlApplicationContext;

/**
 * Service Provider Entry Class
 *
 * Author: Joey Zhu (architectroad@yeah.net)
 * Date: 2017/3/13.
 * Time: 13:58
 */
public class ProdSvcProvider {
    public static void main(String[] args) throws Exception {
        //本地啟動(dòng)spring容器,適用于開(kāi)發(fā)階段調(diào)試
        ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext(
                new String[] {"META-INF/spring/applicationContext.xml"});
        context.start();
        System.out.println("啟動(dòng)成功");
        System.in.read(); // 按任意鍵退出

        //內(nèi)置Tomcat方式啟動(dòng)
//        SpringApplication.run(ProdSvcImpl.class, args);

        //Dubbo spring容器方式啟動(dòng)
//        com.alibaba.dubbo.container.Main.main(args);
    }
}

prodService.provider.xml
<?xml version="1.0" encoding="UTF-8"?>
<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.xsd http://code.alibabatech.com/schema/dubbo http://code.alibabatech.com/schema/dubbo/dubbo.xsd">

       <!-- 提供方應(yīng)用信息,用于計(jì)算依賴關(guān)系 -->
       <dubbo:application name="prodSvcProvider" />

       <!-- 使用multicast廣播注冊(cè)中心暴露服務(wù)地址 -->
       <!--<dubbo:registry address="multicast://224.5.6.7:1234" /> -->

       <!-- 使用zookeeper注冊(cè)中心暴露服務(wù)地址,即zookeeper的所在服務(wù)器ip地址和端口號(hào) -->
       <!-- check: 注冊(cè)中心不存在時(shí)是否報(bào)錯(cuò), subscribe: 是否向此注冊(cè)中心訂閱服務(wù), register: 是否向此注冊(cè)中心注冊(cè)服務(wù) -->
       <dubbo:registry address="zookeeper://127.0.0.1:2181" check="false" subscribe="false" register="true"/>

       <!-- 用dubbo協(xié)議在20880端口暴露服務(wù) -->
       <dubbo:protocol name="dubbo" port="20880" />

       <!-- 具體的實(shí)現(xiàn)bean -->
       <bean id="prodService" class="com.boli.service.impl.prod.ProdSvcImpl"/>
       <!-- 如果使用掃描包方式引入bean,使用如下方式 -->
       <!-- dubbo:annotation package="com.boli.service.impl.*" / -->

       <!-- 聲明需要暴露的服務(wù)接口 -->
       <dubbo:service interface="com.boli.service.intfc.prod.IProdSvc" ref="prodService" version="1.0.0"/>

       <!-- 使用注解方式暴露接口 -->
       <!--dubbo:annotation package="com.boli.service.impl" /-->

       <!-- 加入spring注解掃描 -->
       <!--context:component-scan base-package="com.boli.service.impl"/-->

</beans>
applicationContext.xml
<?xml version="1.0" encoding="UTF-8"?>
<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.xsd http://code.alibabatech.com/schema/dubbo http://code.alibabatech.com/schema/dubbo/dubbo.xsd">
       <!-- import dubbo providers -->
       <import resource="classpath:dubbo/prodService.provider.xml"></import>

</beans>
pom.xml

通過(guò)mvn package命令打包生成prodService-1.0-SNAPSHOT.jar時(shí),指定com.alibaba.dubbo.container.Main作為入口類(lèi),并拷貝所有的依賴包到lib目錄中。打包完成后,使用java -jar prodService-1.0-SNAPSHOT.jar 命令即可運(yùn)行并注冊(cè)服務(wù)到指定的服務(wù)注冊(cè)中心,比如zookeeper。

<?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">
    <modelVersion>4.0.0</modelVersion>
    <groupId>com.boli</groupId>
    <artifactId>prodService</artifactId>
    <version>1.0-SNAPSHOT</version>
    <packaging>jar</packaging>

    <parent>
        <artifactId>prodParentPom</artifactId>
        <groupId>com.boli</groupId>
        <version>1.0-SNAPSHOT</version>
    </parent>

    <dependencies>
        <dependency>
            <groupId>com.boli</groupId>
            <artifactId>prodApi</artifactId>
            <version>1.0-SNAPSHOT</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter</artifactId>
        </dependency>
        <dependency>
            <groupId>org.apache.zookeeper</groupId>
            <artifactId>zookeeper</artifactId>
        </dependency>
    </dependencies>

    <build>
        <resources>
            <resource>
                <!--生成的classes文件的路徑,此文件夾中包含運(yùn)行時(shí)的所有文件,可以不配置-->
                <targetPath>${project.build.directory}/classes</targetPath>
                <directory>src/main/resources</directory>
                <filtering>true</filtering>
                <includes>
                    <include>**/*provider.xml</include>
                    <include>**/*.properties</include>
                </includes>
            </resource>
            <resource>
                <targetPath>${project.build.directory}/classes/META-INF/spring</targetPath>
                <directory>src/main/resources/META-INF/spring</directory>
                <filtering>true</filtering>
                <includes>
                    <include>applicationContext.xml</include>
                </includes>
            </resource>
        </resources>

        <!--下面的必須配置-->
        <plugins>
            <!-- 打包jar文件時(shí),配置manifest文件,加入lib包的jar依賴 -->
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-jar-plugin</artifactId>
                <configuration>
                    <classesDirectory>target/classes/</classesDirectory>
                    <archive>
                        <manifest>
                            <mainClass>com.alibaba.dubbo.container.Main</mainClass>
                            <!-- 打包時(shí) MANIFEST.MF文件不記錄時(shí)間戳版本 -->
                            <useUniqueVersions>false</useUniqueVersions>
                            <addClasspath>true</addClasspath>
                            <classpathPrefix>lib/</classpathPrefix>
                        </manifest>
                        <manifestEntries>
                            <Class-Path>.</Class-Path>
                        </manifestEntries>
                    </archive>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-dependency-plugin</artifactId>
                <executions>
                    <execution>
                        <id>copy-dependencies</id>
                        <phase>package</phase>
                        <goals>
                            <goal>copy-dependencies</goal>
                        </goals>
                        <configuration>
                            <type>jar</type>
                            <includeTypes>jar</includeTypes>
                            <outputDirectory>${project.build.directory}/lib</outputDirectory>
                        </configuration>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>
</project>
  • prodWebApp module
    Web Application。服務(wù)消費(fèi)方。
prodWebApp
ProdController.java
/*
* Copyright (c) 2017 architectroad@yeah.net. All Rights Reserved.
*/
package com.boli.web;

import com.boli.service.intfc.prod.IProdSvc;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;

import java.util.List;

/**
 * Product Controller
 *
 * Author: Joey Zhu (architectroad@yeah.net)
 * Date: 2017/3/10.
 * Time: 18:46
 */
@Controller
public class ProdController {

    @Autowired
    IProdSvc prodService;

    @RequestMapping("/prodList")
    @ResponseBody
    private List<String> getProdList () {
        return prodService.getProdList();
    }
}


ProdWebApplication.java
/*
* Copyright (c) 2017 architectroad@yeah.net. All Rights Reserved.
*/
package com.boli;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.ImportResource;

/**
 * Product Module Web Application
 * Author: Joey Zhu (architectroad@yeah.net)
 * Date: 2017/3/13.
 * Time: 12:16
 */

@EnableAutoConfiguration
@ImportResource({"classpath*:META-INF/spring/applicationContext.xml"})
@ComponentScan("com.boli.web")
public class ProdWebApplication {
    public static void main(String[] args) throws Exception {
        SpringApplication.run(ProdWebApplication.class, args);
    }
}

applicationContext.xml
<?xml version="1.0" encoding="UTF-8"?>
<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.xsd http://code.alibabatech.com/schema/dubbo http://code.alibabatech.com/schema/dubbo/dubbo.xsd">
       <!-- import dubbo consumers -->
       <import resource="classpath*:dubbo/*.consumer.xml"></import>
</beans>
pom.xml
<?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">
    <modelVersion>4.0.0</modelVersion>
    <groupId>com.boli</groupId>
    <artifactId>prodWebApp</artifactId>
    <version>1.0-SNAPSHOT</version>
    <packaging>war</packaging>

    <parent>
        <artifactId>prodParentPom</artifactId>
        <groupId>com.boli</groupId>
        <version>1.0-SNAPSHOT</version>
    </parent>

    <dependencies>
        <dependency>
            <groupId>com.boli</groupId>
            <artifactId>prodApi</artifactId>
            <version>1.0-SNAPSHOT</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>3.8.1</version>
            <scope>test</scope>
        </dependency>
    </dependencies>
</project>

代碼已經(jīng)上傳到GitHub,傳送門(mén)見(jiàn)下:
https://github.com/ArchitectRoad/BoliERP.git

本地測(cè)試步驟及測(cè)試結(jié)果:

  1. 先啟動(dòng)ZooKeeper
joeys-MacBook-Pro:~ joey$ zkServer.sh start
ZooKeeper JMX enabled by default
Using config: /Library/ZooKeeper/zookeeper-3.4.9/bin/../conf/zoo.cfg
Starting zookeeper ... STARTED
joeys-MacBook-Pro:~ joey$ 
  1. 啟動(dòng)ProdSvcProvider


    啟動(dòng)Provider

    從日志中可以看到服務(wù)注冊(cè)成功

INFO com.alibaba.dubbo.registry.zookeeper.ZookeeperRegistry -  [DUBBO] Register: dubbo://192.168.0.109:20880/com.boli.service.intfc.prod.IProdSvc?anyhost=true&application=prodSvcProvider&dubbo=2.5.3&interface=com.boli.service.intfc.prod.IProdSvc&methods=sayHello,getProdList&pid=5836&revision=1.0.0&side=provider&timestamp=1490058278762&version=1.0.0, dubbo version: 2.5.3, current host: 127.0.0.1

3.啟動(dòng)ProdWebApplication


啟動(dòng)Consumer

從日志中可以看到服務(wù)訂閱成功

INFO 5872 --- [           main] c.a.d.r.zookeeper.ZookeeperRegistry      :  [DUBBO] Subscribe: consumer://192.168.0.109/com.boli.service.intfc.prod.IProdSvc?application=prodSvcConsumer&category=providers,configurators,routers&default.timeout=5000&dubbo=2.5.3&interface=com.boli.service.intfc.prod.IProdSvc&methods=sayHello,getProdList&pid=5872&revision=1.0.0&side=consumer&timestamp=1490058693542&version=1.0.0, dubbo version: 2.5.3, current host: 192.168.0.109

4.訪問(wèn)應(yīng)用
訪問(wèn)本地接口,驗(yàn)證web應(yīng)用部署成功


測(cè)試本地接口

訪問(wèn)遠(yuǎn)程服務(wù)接口,驗(yàn)證Dubbo遠(yuǎn)程服務(wù)調(diào)用成功


訪問(wèn)zk注冊(cè)服務(wù)
最后編輯于
?著作權(quán)歸作者所有,轉(zhuǎn)載或內(nèi)容合作請(qǐng)聯(lián)系作者
【社區(qū)內(nèi)容提示】社區(qū)部分內(nèi)容疑似由AI輔助生成,瀏覽時(shí)請(qǐng)結(jié)合常識(shí)與多方信息審慎甄別。
平臺(tái)聲明:文章內(nèi)容(如有圖片或視頻亦包括在內(nèi))由作者上傳并發(fā)布,文章內(nèi)容僅代表作者本人觀點(diǎn),簡(jiǎn)書(shū)系信息發(fā)布平臺(tái),僅提供信息存儲(chǔ)服務(wù)。

相關(guān)閱讀更多精彩內(nèi)容

友情鏈接更多精彩內(nèi)容