spring boot集成zookeeper注冊中心

ZooKeeper是一個分布式服務框架，是Apache Hadoop 的一個子項目，它主要是用來解決分布式應用中經常遇到的一些數據管理問題，如：統一命名服務、狀態同步服務、集群管理、分布式應用配置項的管理等

ZooKeeper是一個樹形結構的目錄服務，支持變更推送

在ZooKeeper中，節點分為兩類：

　　機器節點：

　　　　指構成集群的機器

　　數據節點ZNode：

　　　　指數據模型中的數據單元　　

　　　　ZooKeeper將所有數據存儲在內存中，數據模型是一棵樹(ZNode Tree)，由斜杠（/）進行分割的路徑，就是一個ZNode，例如/services/customer

　　　　每個ZNode上都會保存自己的數據內容，同時還會保存一系列屬性信息

　　　　Znode可分為：

　　　　　　持久節點：指一旦這個ZNode被創建了，除非主動進行ZNode的移除操作，否則這個ZNode將一直保存在ZooKeeper上

　　　　　　臨時節點：它的生命周期和客戶端會話綁定，一旦客戶端會話失效，那么這個客戶端創建的所有臨時節點都會被移除

1.docker安裝

docker pull zookeeper:3.5

2.啟動

docker run --name zookeeper -p 2181:2181 -d zookeeper:3.5

3.使用

provider

依賴

<properties>
        <java.version>1.8</java.version>
        <spring-cloud.version>Greenwich.SR3</spring-cloud.version>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-zookeeper-discovery</artifactId>
        </dependency>
    </dependencies>
    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>${spring-cloud.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>

配置

server.port=8010
spring.application.name=service-provider
management.endpoints.web.exposure.include=*
management.endpoint.health.show-details=always
spring.cloud.zookeeper.connect-string=192.168.99.100:2181

啟動類

package com.xyz.provider;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;

@EnableDiscoveryClient
@SpringBootApplication
public class ProviderApplication {

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

}

控制器

package com.xyz.provider.controller;

import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

@RestController
public class demoController {
    @RequestMapping("/hello")
    public String Hello() {
        return "hello,provider";
    }

}

comsumer

添加依賴

<properties>
        <java.version>1.8</java.version>
        <spring-cloud.version>Hoxton.SR1</spring-cloud.version>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-openfeign</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-zookeeper-discovery</artifactId>
        </dependency>
    </dependencies>
    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>${spring-cloud.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>

配置

server.port=8015
spring.application.name=service-comsumer
management.endpoints.web.exposure.include=*
management.endpoint.health.show-details=always
feign.client.config.default.connect-timeout=500
feign.client.config.default.read-timeout=500
spring.cloud.zookeeper.connect-string=192.168.99.100:2181

啟動類

package com.xyz.comsumer;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.loadbalancer.LoadBalanced;
import org.springframework.cloud.openfeign.EnableFeignClients;
import org.springframework.context.annotation.Bean;
import org.springframework.web.client.RestTemplate;

@EnableFeignClients
@SpringBootApplication
public class ComsumerApplication {

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

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

}

控制器

package com.xyz.comsumer.controller;

import com.xyz.comsumer.feign.RemoteHelloService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

@RestController
public class FeignController {
    @Autowired
    RemoteHelloService remoteHelloService;

    @RequestMapping("feignTest")
    public String feignTest() {
        String result = remoteHelloService.hello();
        if (result == null) {
            result = "出錯";
        }
        return result;
    }
    
}

啟動provider

啟動comsumer

測試 GET http://127.0.0.1:8015/feignTest

輸出

　　hello,provider

4.查看

在docker中進入zookeeper命令行

docker exec -it zookeeper bash

進入zookeeper的bin目錄

cd bin

使用zookeeper client訪問zookeeper服務

./zkCli.sh

查看當前 ZooKeeper 中所包含的內容

[zk: localhost:2181(CONNECTED) 1] ls /
[services, zookeeper]

查看所有services

[zk: localhost:2181(CONNECTED) 2] ls /services
[service-comsumer, service-provider]

查看service-comsumer的信息

[zk: localhost:2181(CONNECTED) 13] ls /services/service-comsumer
[efac86a0-1d0c-47e8-8f29-998661f50e04]

根據[id]查看相關服務的詳細信息

[zk: localhost:2181(CONNECTED) 23] ls /services/service-comsumer
[f8c462b5-a6e6-4861-b20d-e48cdcdda207]
[zk: localhost:2181(CONNECTED) 24] get /services/service-comsumer/f8c462b5-a6e6-4861-b20d-e48cdcdda207
{"name":"service-comsumer","id":"f8c462b5-a6e6-4861-b20d-e48cdcdda207","address":"hkgi-PC","port":8015,"sslPort":null,"payload":{"@class":"org.springframework.cloud.zookeeper.discovery.ZookeeperInstance","id":"service-comsumer-1","name":"service-comsumer","metadata":{}},"registrationTimeUTC":1586917597776,"serviceType"
:"DYNAMIC","uriSpec":{"parts":[{"value":"scheme","variable":true},{"value":"://","variable":false},{"value":"address","variable":true},{"value":":","variable":false},{"value":"port","variable":true}]}}