基于Zookeeper的配置中心

上一篇 spring boot集成zookeeper注册中心

现在看下基于基于Zookeeper的配置中心实现

在Zookeeper建立一个根节点，比如/config，代表某个配置文件

让所有使用到该配置信息的应用机器集成Zookeeper并监控/config的状态

一旦配置信息也就是子节点发生变化，每台应用机器就会收到ZK的通知，然后从ZK中获取新的配置信息应用到系统中

1.依赖

<dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
     　　<artifactId>spring-boot-starter-web</artifactId>
　　</dependency>
　　<dependency>
     <groupId>org.projectlombok</groupId>
     <artifactId>lombok</artifactId>
　　</dependency>
　　<dependency>
     　　<groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-starter-zookeeper-config</artifactId>
    </dependency>
</dependencies>

2.创建配置文件

使用@ConfigurationProperties 特性，标记类为配置文件

package com.xyz.provider;

import lombok.Data;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.cloud.context.config.annotation.RefreshScope;
import org.springframework.stereotype.Component;

@ConfigurationProperties("order")
@RefreshScope
@Data
@Component
public class OrderProperties {
    private Integer discount = 100;
}

3.控制器

package com.xyz.provider.controller;

import com.xyz.provider.OrderProperties;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

@RestController
public class demoController {
    @Autowired
    private OrderProperties orderProperties;

    @RequestMapping("/search")
    public Integer searchDiscount() {
        return orderProperties.getDiscount();
    }
}

4.启用配置

server.port=8010
management.endpoints.web.exposure.include=*
management.endpoint.health.show-details=always
spring.profiles.active=dev
spring.application.name=config-demo
spring.cloud.zookeeper.connect-string=192.168.99.100:2181
spring.cloud.zookeeper.config.root=config
spring.cloud.zookeeper.config.enabled=true
spring.cloud.zookeeper.config.watcher.enabled=true
spring.cloud.zookeeper.config.profileSeparator=:

注：

　　配置文件bootstrap.yml / bootstrap.properties中加入zookeeper连接信息

　　写到application.properties会报错

 Opening socket connection to server localhost/0:0:0:0:0:0:0:1:2181. Will not attempt to authenticate using SASL

因为配置的组合顺序为

应用名-profile.properties
应用名.properties
application-profile.properties
application.properties

6.在Zookeeper中手动创建配置

根据上面的配置

create /config
create /config/config-demo
create /config/config-demo:dev
create /config/config-demo:dev/order.discount 60

获取值

 get /config/config-demo:dev/order.discount

启动项目

测试 GET http://localhost:8010/search

获取的为60

修改

set /config/config-demo:dev/order.discount 70

不用重启直接获取的为70