springboot 使用zookeeper实现服务注册和发现

一、目录结构

此项目实例是使用多模块maven，并配合springboot进行构建
结构如下图所示

image.png

二、每个maven的配置

这里是父maven的配置




    4.0.0
    pom
    
        order
        product
    
    
        org.springframework.boot
        spring-boot-starter-parent
        2.0.2.RELEASE
        
    


    com.example
    springboot_zookeeper
    0.0.1-SNAPSHOT
    springboot_zookeeper
    Demo project for Spring Boot

    
        1.8
    

    
        
            org.springframework.boot
            spring-boot-starter-web
        

        
            org.springframework.boot
            spring-boot-starter-test
            test
        

        
            org.apache.zookeeper
            zookeeper
            3.4.12
        
        
            com.101tec
            zkclient
            0.10
        

        
            org.apache.curator
            curator-framework
            4.0.0
        

        
            org.apache.curator
            curator-recipes
            4.0.0
        
    

    
        
            
                org.apache.maven.plugins
                maven-compiler-plugin
                
                    1.8
                    1.8
                    UTF-8

order服务下的maven



    
        springboot_zookeeper
        com.example
        0.0.1-SNAPSHOT
    
    4.0.0

    order

product服务下的maven



    
        springboot_zookeeper
        com.example
        0.0.1-SNAPSHOT
    
    4.0.0

    product

三、product模块

此模块下的Application代码

package com.example.product;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.Bean;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RestController;

import javax.servlet.http.HttpServletRequest;
import java.io.InputStream;
import java.util.Properties;

@SpringBootApplication
@RestController
public class Application {


    public static void main(String[] args) {
        SpringApplication.run(Application.class,args);

    }

    @RequestMapping(value = "/product/id",method = RequestMethod.GET)
    public String  get(HttpServletRequest request){
        return "访问 product  服务端口："+ request.getLocalPort();
    }

    @Bean
    public Register register(){
        Register register = new Register();
        register.register11(getAddressAndPort());
        return register;
    }


    private String getAddressAndPort(){
        try {
            Properties properties = new Properties();
            InputStream stream = Application.class.getClassLoader().getResourceAsStream("application.properties");
            properties.load(stream);

            Object port = properties.get("server.port");
            return "127.0.0.1:" + port;
        }catch (Exception e){
            throw new RuntimeException();
        }
    }
}

使用Register实现服务的注册

package com.example.product;

import org.apache.zookeeper.CreateMode;
import org.apache.zookeeper.ZooDefs;
import org.apache.zookeeper.ZooKeeper;
import org.apache.zookeeper.data.Stat;

public class Register {

    private static final String SERVER_PATH = "/product";

    private static final String ZK_ADDRESS = "94.*.*.51:4180";

    private static final int ZK_TIMEOUT = 20000;

    public void register11(String address){
        try{
            ZooKeeper zooKeeper = new ZooKeeper(ZK_ADDRESS,ZK_TIMEOUT, WatchEvent ->{

            });
            Stat stat = zooKeeper.exists(SERVER_PATH,false);
            if(stat==null){
                zooKeeper.create(SERVER_PATH,"".getBytes(), ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
            }
            String path = address;
            //创建短暂的可排序的子节点
            zooKeeper.create(SERVER_PATH+"/instance",path.getBytes(),ZooDefs.Ids.OPEN_ACL_UNSAFE,CreateMode.EPHEMERAL_SEQUENTIAL);
        }catch (Exception e){
            e.printStackTrace();
        }
    }
}

此模块中对应的application.properties配置

server.port=8086

四、order模块

此模块下的Application代码

package com.example.order;



import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.Bean;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.client.RestTemplate;

import javax.annotation.Resource;

@SpringBootApplication
@RestController
public class Application {

    @Resource
    private RestTemplate restTemplate;

    @Resource
    private ZookListener listener;

    @Bean
    public RestTemplate restTemplate(){
        return new RestTemplate();
    }

    @Bean
    public ZookListener zookListener(){
        ZookListener listener = new ZookListener();
        listener.init();
        return listener;
    }

    @RequestMapping(value = "/order/id",method = RequestMethod.GET)
    public String get(){
        //从zookeeper中获取调用的ip
        String path = listener.getPath();
        if(path == null){
            return "对不起，产品暂时停止服务！";
        }
        return restTemplate.getForObject("http://"+listener.getPath()+"/product/id",String.class);
    }


    public static void main(String[] args) {
        SpringApplication.run(Application.class,args);
    }
}

此模块下使用ZookListener类实现获取zookeeper的节点列表，也可以监听zookeeper里面的节点变化

package com.example.order;

import org.apache.zookeeper.Watcher;
import org.apache.zookeeper.ZooKeeper;

import java.util.LinkedList;
import java.util.List;
import java.util.Random;


public class ZookListener {

    private static final String SERVER_PATH="/product";

    private static final String ZK_ADDRESS="94.*.*.51:4180";

    private static final int ZK_TIMEOUT = 20000;

    private ZooKeeper zooKeeper;

    private List paths = new LinkedList<>();

    public void init(){
        try{
            zooKeeper = new ZooKeeper(ZK_ADDRESS,ZK_TIMEOUT,(WatchEvent)->{
                getChilds();
            });
        }catch (Exception e){
            e.printStackTrace();
        }
    }

    private void getChilds(){
        List ips = new LinkedList<>();
        try{
            //添加监听
            List childs = this.zooKeeper.getChildren(SERVER_PATH,true);
            for(String child:childs){
                byte[] obj = zooKeeper.getData(SERVER_PATH+"/"+child,false,null);
                String path = new String(obj,"utf-8");
                ips.add(path);
            }
            this.paths = ips;
        }catch (Exception e){
            e.printStackTrace();
        }
    }

    public String getPath(){
        if(paths.isEmpty()){
            return null;
        }
        int index = new Random().nextInt(paths.size());
        return paths.get(index);
    }
}

此模块中的application.properties