zookeeper服务注册与发现

前提：zookeeper服务已开启，dubbo-admin已下载

1，项目基本结构：

注：service路径接口名要相同

2，服务提供者提供服务（provider-service）

1.导入依赖

 <!--导入dubbo+zookeeper依赖-->
        <!-- https://mvnrepository.com/artifact/org.apache.dubbo/dubbo-spring-boot-starter -->
        <dependency>
            <groupId>org.apache.dubbo</groupId>
            <artifactId>dubbo-spring-boot-starter</artifactId>
            <version>2.7.3</version>
        </dependency>

        <!--导入zkClientr依赖-->
        <!-- https://mvnrepository.com/artifact/com.github.sgroschupf/zkclient -->
        <dependency>
            <groupId>com.github.sgroschupf</groupId>
            <artifactId>zkclient</artifactId>
            <version>0.1</version>
        </dependency>

        <!--日志冲突-->
        <!--引入zookeeper-->
        <!-- https://mvnrepository.com/artifact/org.apache.curator/curator-framework -->
        <dependency>
            <groupId>org.apache.curator</groupId>
            <artifactId>curator-framework</artifactId>
            <version>2.12.0</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/org.apache.curator/curator-recipes -->
        <dependency>
            <groupId>org.apache.curator</groupId>
            <artifactId>curator-recipes</artifactId>
            <version>2.12.0</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/org.apache.zookeeper/zookeeper -->
        <dependency>
            <groupId>org.apache.zookeeper</groupId>
            <artifactId>zookeeper</artifactId>
            <version>3.4.14</version>

            <!--排除slf4j-log4j12-->
            <exclusions>
                <exclusion>
                    <groupId>org.slf4j</groupId>
                    <artifactId>slf4j-log4j12</artifactId>
                </exclusion>
            </exclusions>
        </dependency>

2.配置注册中心的地址，服务应用的名字，要被扫描的包

server.port=8001

# 服务应用的名字
dubbo.application.name=provider-server
#注册中心地址
dubbo.registry.address=zookeeper://localhost:2181
#哪些服务要被注册
dubbo.scan.base-packages=com.example.service

3.在service包下新建TickService服务接口及TickServiceImpl实现类

TickService.Interface

package com.example.service;

public interface TickService {
    public String getTicket();
}

TickServiceIml.class

package com.example.service;

import org.apache.dubbo.config.annotation.Service;
import org.springframework.stereotype.Component;

//可以被扫描到，在项目已启动就自动注册到注册中心
@Service//将服务发布出去
@Component //使用了dubbo一般不使用service注解
public class TickServiceImpl implements TickService {
    @Override
    public String getTicket() {
        return "TickService!!!!";
    }
}

在想要被发现注册的服务上增加一个@Service（dubbo）的注解

4，测试，启动provider-service，访问http://localhost:7001/，可以看到服务已被注册

3，消费者消费服务

1.pom依赖导入

<!--导入dubbo+zookeeper依赖-->
        <!-- https://mvnrepository.com/artifact/org.apache.dubbo/dubbo-spring-boot-starter -->
        <dependency>
            <groupId>org.apache.dubbo</groupId>
            <artifactId>dubbo-spring-boot-starter</artifactId>
            <version>2.7.3</version>
        </dependency>

        <!--导入zkClientr依赖-->
        <!-- https://mvnrepository.com/artifact/com.github.sgroschupf/zkclient -->
        <dependency>
            <groupId>com.github.sgroschupf</groupId>
            <artifactId>zkclient</artifactId>
            <version>0.1</version>
        </dependency>

        <!--日志冲突-->
        <!--引入zookeeper-->
        <!-- https://mvnrepository.com/artifact/org.apache.curator/curator-framework -->
        <dependency>
            <groupId>org.apache.curator</groupId>
            <artifactId>curator-framework</artifactId>
            <version>2.12.0</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/org.apache.curator/curator-recipes -->
        <dependency>
            <groupId>org.apache.curator</groupId>
            <artifactId>curator-recipes</artifactId>
            <version>2.12.0</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/org.apache.zookeeper/zookeeper -->
        <dependency>
            <groupId>org.apache.zookeeper</groupId>
            <artifactId>zookeeper</artifactId>
            <version>3.4.14</version>

            <!--排除slf4j-log4j12-->
            <exclusions>
                <exclusion>
                    <groupId>org.slf4j</groupId>
                    <artifactId>slf4j-log4j12</artifactId>
                </exclusion>
            </exclusions>
        </dependency>

2.properties配置文件配置

server.port=8002

# 消费者拿服务需要暴露自己的名字
dubbo.application.name=customer-server
# 注册中心的地址
dubbo.registry.address=zookeeper://localhost:2181

3.本来正常步骤是需要将服务提供者的接口打包，然后用pom文件导入，我们这里使用简单的方式，直接将服务的接口拿过来，路径必须保证正确，即和服务提供者相同；

4.完善消费者的服务类,使用@Reference从远程注入服务

package com.example.service;

import org.apache.dubbo.config.annotation.Reference;
import org.springframework.stereotype.Service;

@Service
public class UserService {
    //获取到provider-service提供的服务,要去注册中心拿到服务

    @Reference //引用，Pom坐标，可以定义路径相同的接口名;
	//远程引用指定的服务，他会按照全类名进行匹配，看谁给注册中心注册了这个全类名
    TickService tickService;
    public void  buyTicket(){
        String ticket = tickService.getTicket();
        System.out.println("在注册中心拿到TickService"+ticket);
    }
}

5.测试，编写测试，启动cuntomer-service项目，浏览器访问http://localhost:7001/governance/consumers，并查看控制台输出！

    @Test
    void contextLoads() {
        userService.buyTicket();
    }