基于Dubbo和Zookeeper实现服务间通信DEMO

た入场券 2022-05-16 08:09 175阅读 0赞

# 环境准备 #

\* zookeeper单点或集群环境，演示使用集群

\* 基于maven进行项目构建

\* 必要jar包依赖

# 无注册中心的dubbo协调通信 #

1，服务端整体结构

a，服务端项目框架

![70][]

-- dubbo-server为服务端整体项目结构，其下分有两个子模块，dubbo-api和dubbo-service

-- dubbo-api为服务端对外接口，依赖于dubbo-service

-- dubbo-service为依赖dubbo-api，为dubbo-api中接口的实现类，具体实现对外接口

-- 服务端对外接口提供只需提供dubbo-api，而具体实现的dubbo-service则对外隐藏

-- 如果包依赖后一直错误提示不存在，记得对server-api-service依次install

b，dubbo-api模块

\* pom文件

dubbo-api只负责对外提供接口，无需依赖包结构，除非接口传参有特殊需求

\* 接口文件

public interface IDubboDemoService {
    
        String showMsg(String msg);
    }

c，dubbo-service模块

\* pom文件

-- 不依赖zookeeper注册中心的通信， 只需要依赖dubbo和接口包进行服务发布

<dependency>
                <groupId>com.gupao.dubbo</groupId>
                <artifactId>dubbo-api</artifactId>
                <version>1.0-SNAPSHOT</version>
            </dependency>
            <dependency>
                <groupId>com.alibaba</groupId>
                <artifactId>dubbo</artifactId>
                <version>2.5.3</version>
            </dependency>

\* 接口实现类

-- 对接口做一个简单实现

public class DubboDemoService implements IDubboDemoService {
        @Override
        public String showMsg(String msg) {
            return "HELLO : " + msg;
        }
    }

\* 配置文件 -- dubbo.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"
           xmlns:bean="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">
    
        
        <dubbo:application name="dubbo-server" owner="ZPJ"/>
    
        
        <dubbo:registry address="N/A"/>
    
        
        <dubbo:protocol name="dubbo" port="20880"/>
    
        
        <dubbo:service interface="com.gupao.dubbo.IDubboDemoService" ref="gupaoHello"/>
    
        
        <bean id="gupaoHello" class="com.gupao.dubbo.impl.DubboDemoService"/>
    
    </beans>

\* 配置文件 -- log4j.properties

### direct log messages to stdout ###
    log4j.appender.stdout=org.apache.log4j.ConsoleAppender
    log4j.appender.stdout.Target=System.out
    log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
    log4j.appender.stdout.layout.ConversionPattern=%d{ABSOLUTE} %5p %c{1}:%L - %m%n
    
    ### direct messages to file mylog.log ###
    log4j.appender.file=org.apache.log4j.FileAppender
    log4j.appender.file.File=c:/mylog.log
    log4j.appender.file.layout=org.apache.log4j.PatternLayout
    log4j.appender.file.layout.ConversionPattern=%d{ABSOLUTE} %5p %c{1}:%L - %m%n
    
    ### set log levels - for more verbose logging change 'info' to 'debug' ###
    
    log4j.rootLogger=info, stdout

d，基本Spring发布服务（Spring为dubbo依赖包，无需刻意引入）

public class DubboDemoTest {
        public static void main(String[] args) throws IOException {
            // 加载配置文件
            ClassPathXmlApplicationContext context =
                    new ClassPathXmlApplicationContext("dubbo-server.xml");
            // 启动容器
            context.start();
            System.in.read();
        }
    }

e，服务端启动效果

-- 标注出来链接为无注册中心时，客户端需要引用的服务链接

![70 1][]

2，客户端整体结构

a，pom文件

-- 引用必要的服务端对外接口jar包和dubbo包

<dependency>
          <groupId>com.alibaba</groupId>
          <artifactId>dubbo</artifactId>
          <version>2.5.3</version>
        </dependency>
        <dependency>
          <groupId>com.gupao.dubbo</groupId>
          <artifactId>dubbo-api</artifactId>
          <version>1.0-SNAPSHOT</version>
        </dependency>
        <dependency>

b，配置文件 -- dubbo.xml

-- 无注册中心时，dubbo引用服务需要添加url路径，路径为服务端启动日志中标注的内容

<?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"
           xmlns:bean="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">
    
        
        <dubbo:application name="dubbo-server" owner="ZPJ"/>
    
        
        <dubbo:registry address="N/A"/>
    
        
        <dubbo:protocol name="dubbo" port="20880"/>
    
        
        <dubbo:reference id="gupaoHello" interface="com.gupao.dubbo.IDubboDemoService"
            url="dubbo://192.168.93.1:20880/com.gupao.dubbo.IDubboDemoService"/>
    
    </beans>

c，客户端调用

public class demo {
        public static void main(String[] args) throws InterruptedException {
            ClassPathXmlApplicationContext context =
                    new ClassPathXmlApplicationContext("dubbo-master.xml");
            for (int i = 0; i < 10; i++) {
                IDubboDemoService service = (IDubboDemoService) context.getBean("gupaoHello");
                System.out.println(service.showMsg("DUBBO连接成功"));
                Thread.sleep(2000);
            }
        }
    }

d，执行结果

![70 2][]

3，无注册中心的dubbo协调通信完成，后续在此基础上扩展

# 有注册中心的dubbo协调通信 #

1，给服务端添加注册中心配置 -- 注册中心应用zookeeper注册中心

\* 修改dubbo.xml文件，只需修改注册中心那一条配置，此处引用的是zookeeper集群

<dubbo:registry protocol="zookeeper" address="192.168.91.128:2181,192.168.91.129:2181,192.168.91.130:2181"/>

\* 服务启动

-- 通过日志可以看到，服务已经注册到zookeeper注册中心

![70 3][]

\* zookeeper客户端节点查看

![70 4][]

2，客户端添加注册中心配置

a，配置文件 -- dubbo.xml

-- 添加zookeeper注册中心

<dubbo:registry protocol="zookeeper" address="192.168.91.128:2181,192.168.91.129:2181,192.168.91.130:2181"/>

-- 接口引用取消URL属性，dubbo会自动从注册中心读取

<dubbo:reference id="gupaoHello" interface="com.gupao.dubbo.IDubboDemoService"/>

b，客户端调用

c，结果分析

\* 从日志中可以看到客户端请求通过zookeeper和dubbo连接到服务端的全过程

![70 5][]

# 服务端集群下的dubbo协调通信 #

1，服务端集群测试，是为了测试dubbo自身所提供的负载均衡机制；集群测试，只变更服务端服务为集群情况，客户端不变更

2，服务端变更集群

\* 以多服务模拟集群下的多节点

public class DubboCluster1Service implements IDubboDemoService {
        @Override
        public String showMsg(String msg) {
            return "I'm cluster_1 service : " + msg;
        }
    }

public class DubboCluster2Service implements IDubboDemoService {
        @Override
        public String showMsg(String msg) {
            return "I'm cluster_2 service : " + msg;
        }
    }

\* 配置文件配置不同的端口号模拟集群机器

-- dubbo-cluster\_1.xml

<dubbo:protocol name="dubbo" port="20880"/>

-- dubbo-cluster\_2.xml

<dubbo:protocol name="dubbo" port="20881"/>

\* 分别启动两台服务

-- 启动第一台

public class DubboClusterTest_1 {
        public static void main(String[] args) throws IOException {
            ClassPathXmlApplicationContext context =
                    new ClassPathXmlApplicationContext("dubbo-cluster-1.xml");
            context.start();
            System.in.read();
        }
    }

![70 6][]

-- 启动第二台

public class DubboClusterTest_2 {
        public static void main(String[] args) throws IOException {
            ClassPathXmlApplicationContext context =
                    new ClassPathXmlApplicationContext("dubbo-cluster-2.xml");
            context.start();
            System.in.read();
        }
    }

![70 7][]

\* 查看zookeeper节点

![70 8][]

3，客户端代码不变，直接调用，查看结果

-- 十次循环，类似于之前写到的通过随机数实现负载均衡，服务1和服务2各有分配执行

![70 9][]

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