Spring Boot整合Zookeeper详细教程

注意我这里用的是官方最稳定的版本3.7.1，版本之间有个别命令是有差距的！

本篇文章的示例SpringBoot和Zookeeper客户端以及zookeeper都是最新版本！

1.Curator介绍

Curator是Netflix公司开源的⼀套zookeeper客户端框架，Curator是对Zookeeper⽀持最好的客户端框架。Curator封装了⼤部分Zookeeper的功能，⽐如Leader选举、分布式锁等，减少了技术⼈员在使⽤Zookeeper时的底层细节开发⼯作。

2.创建springboot项目

3.引⼊Curator

<?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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
	<modelVersion>4.0.0</modelVersion>
	<parent>
		<groupId>org.springframework.boot</groupId>
		<artifactId>spring-boot-starter-parent</artifactId>
		<version>2.7.0</version>
		<relativePath/>
	</parent>
	<groupId>com.gzl.cn</groupId>
	<artifactId>spring-boot-curator-zk</artifactId>
	<version>0.0.1-SNAPSHOT</version>
	<name>spring-boot-curator-zk</name>
	<description>Demo project for Spring Boot</description>
	<properties>
		<java.version>1.8</java.version>
	</properties>
	<dependencies>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-web</artifactId>
		</dependency>

		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-test</artifactId>
			<scope>test</scope>
		</dependency>

        <!--Curator-->
		<dependency>
			<groupId>org.apache.curator</groupId>
			<artifactId>curator-framework</artifactId>
			<version>5.2.1</version>
		</dependency>
		 <dependency>
			<groupId>org.apache.curator</groupId>
			<artifactId>curator-recipes</artifactId>
			<version>5.2.1</version>
		</dependency>
        <!--Zookeeper-->
        <dependency>
			<groupId>org.apache.zookeeper</groupId>
			<artifactId>zookeeper</artifactId>
			<version>3.8.0</version>
		</dependency>

		<dependency>
			<groupId>org.projectlombok</groupId>
			<artifactId>lombok</artifactId>
			<version>1.18.22</version>
			<scope>provided</scope>
		</dependency>

		<!--解决Spring Boot Configuration Annotation Processor not configured提示问题-->
		<dependency>
			 <groupId>org.springframework.boot</groupId>
			 <artifactId>spring-boot-configuration-processor</artifactId>
			 <optional>true</optional>
		</dependency>

		<dependency>
			<groupId>junit</groupId>
			<artifactId>junit</artifactId>
			<scope>4.12</scope>
		</dependency>
	</dependencies>

	<build>
		<plugins>
			<plugin>
				<groupId>org.apache.maven.plugins</groupId>
				<artifactId>maven-resources-plugin</artifactId>
				<version>3.1.0</version>
			</plugin>
			<plugin>
				<groupId>org.springframework.boot</groupId>
				<artifactId>spring-boot-maven-plugin</artifactId>
			</plugin>
		</plugins>
	</build>

</project>

4.application.yml配置⽂件

application.yml和application.properties是都可以的，只不过他们的格式不一样。

curator:
  #重试retryCount次，当会话超时出现后，curator会每间隔elapsedTimeMs毫秒时间重试一次，共重试retryCount次。
  retryCount: 5
  elapsedTimeMs: 5000
  #服务器信息
  connectString: 127.0.0.1:2181
  #会话超时时间设置
  sessionTimeoutMs: 60000
  #连接超时时间
  connectionTimeoutMs: 5000

5.读取配置⽂件注入到容器

import lombok.Data;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.stereotype.Component;

@Data
@Component
@ConfigurationProperties(prefix = "curator")
public class WrapperZK {
    private int retryCount;
    private int elapsedTimeMs;
    private String connectString;
    private int sessionTimeoutMs;
    private int connectionTimeoutMs;
}

6.注⼊CuratorFramework

import org.apache.curator.framework.CuratorFramework;
import org.apache.curator.framework.CuratorFrameworkFactory;
import org.apache.curator.retry.RetryNTimes;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

@Configuration
public class CuratorConfig {
    @Autowired
    WrapperZK wrapperZk;

    /**
     * 这里的start就是创建完对象放到容器后，需要调用他的start方法
     *
     * @return
     */
    @Bean(initMethod = "start")
    public CuratorFramework curatorFramework() {
        return CuratorFrameworkFactory.newClient(
                wrapperZk.getConnectString(),
                wrapperZk.getSessionTimeoutMs(),
                wrapperZk.getConnectionTimeoutMs(),
                new RetryNTimes(wrapperZk.getRetryCount(), wrapperZk.getElapsedTimeMs()));
    }
}

7.添加测试方法

在这里添加测试方法即可！

import org.apache.curator.framework.CuratorFramework;
import org.apache.zookeeper.CreateMode;
import org.junit.jupiter.api.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;

@RunWith(SpringRunner.class)
@SpringBootTest(classes = SpringBootCuratorZkApplication.class)
class SpringBootCuratorZkApplicationTests {

    @Autowired
    CuratorFramework curatorFramework;

    /**
     * 创建节点
     *
     * @throws Exception
     */
    @Test
    void createNode() throws Exception {
        // 添加持久节点
        String path = curatorFramework.create().forPath("/curator-node");
        System.out.println(String.format("curator create node :%s successfully.", path));

        // 添加临时序号节点,并赋值数据
        String path1 = curatorFramework.create()
                .withMode(CreateMode.EPHEMERAL_SEQUENTIAL)
                .forPath("/curator-node", "some-data".getBytes());
        System.out.println(String.format("curator create node :%s successfully.", path));

        // System.in.read()目的是阻塞客户端关闭，我们可以在这期间查看zk的临时序号节点
        // 当程序结束时候也就是客户端关闭的时候，临时序号节点会消失
        System.in.read();
    }

    /**
     * 获取节点
     *
     * @throws Exception
     */
    @Test
    public void testGetData() throws Exception {
        // 在上面的方法执行后，创建了curator-node节点，但是我们并没有显示的去赋值
        // 通过这个方法去获取节点的值会发现，当我们通过Java客户端创建节点不赋值的话默认就是存储的创建节点的ip
        byte[] bytes = curatorFramework.getData().forPath("/curator-node");
        System.out.println(new String(bytes));
    }

    /**
     * 修改节点数据
     *
     * @throws Exception
     */
    @Test
    public void testSetData() throws Exception {
        curatorFramework.setData().forPath("/curator-node", "changed!".getBytes());
        byte[] bytes = curatorFramework.getData().forPath("/curator-node");
        System.out.println(new String(bytes));
    }

    /**
     * 创建节点同时创建⽗节点
     *
     * @throws Exception
     */
    @Test
    public void testCreateWithParent() throws Exception {
        String pathWithParent = "/node-parent/sub-node-1";
        String path = curatorFramework.create().creatingParentsIfNeeded().forPath(pathWithParent);
        System.out.println(String.format("curator create node :%s successfully.", path));
    }

    /**
     * 删除节点(包含子节点)
     *
     * @throws Exception
     */
    @Test
    public void testDelete() throws Exception {
        String pathWithParent = "/node-parent";
        curatorFramework.delete().guaranteed().deletingChildrenIfNeeded().forPath(pathWithParent);
    }
}

8.执行测试方法报错解决

上面那个闪电意思是install的时候跳过maven测试阶段，之所以要跳过测试阶段是因为假如不跳过他会验证测试方法，例如我们创建节点的方法，有时候我们节点已经创建了，但是他还会验证，所以就会报错。

源码地址：https://gitee.com/gzl_com/spring-cloud.git