Nacos 分布式配置中心

在分布式系统中，由于服务数量巨多，为了方便服务配置文件统一管理，实时更新，所以需要分布式配置中心组件

接入配置中心

<?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.</modelVersion>

    <parent>

        <groupId>org.springframework.boot</groupId>

        <artifactId>spring-boot-starter-parent</artifactId>

        <version>2.0..RELEASE</version>

        <relativePath/> <!-- lookup parent from repository -->

    </parent>

    <groupId>nacos.server</groupId>

    <artifactId>nacos.server</artifactId>

    <name>nacos.server</name>

    <description>Demo project for Spring Boot</description>

    <properties>

        <java.version>1.8</java.version>

        <spring-boot.version>2.0..RELEASE</spring-boot.version>

        <nacos-config-spring-boot.version>0.2.</nacos-config-spring-boot.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-alibaba-nacos-config</artifactId>

            <version>0.2..RELEASE</version>

        </dependency>

        <dependency>

            <groupId>io.springfox</groupId>

            <artifactId>springfox-swagger2</artifactId>

            <version>2.5.</version>

        </dependency>

        <!-- swagger-ui -->

        <dependency>

            <groupId>io.springfox</groupId>

            <artifactId>springfox-swagger-ui</artifactId>

            <version>2.5.</version>

        </dependency>

    </dependencies>

</project>

新增控制器

应用会从 Nacos Config 中获取相应的配置，并添加在 Spring Environment 的 PropertySources 中。这里我们使用 @Value 注解来将对应的配置注入到ConfigController中的字段，并添加 @RefreshScope 打开动态刷新功能

@RestController

@RequestMapping("/config")

@RefreshScope

public class ConfigController {

    @Value("${useLocalCache:false}")

    private boolean useLocalCache;

    @Value("${user.name}")

    private String userName;

    @Value("${user.age}")

    private Integer userAge;

    /**

     * http://localhost:8080/config/get

     */

    @RequestMapping("/get")

    @ResponseBody

    public String get() {

        return "useLocalCache:" + useLocalCache + " userName:" + userName + " userAge:" + userAge;

    }

}

新增注册配置

bootstrap.properties增加以下配置

spring.cloud.nacos.config.server-addr=192.168.50.31:8848 --配置地址

spring.application.name=service-provider  --dataid

spring.profiles.active=test   --运行环境

server.port=

登录Nacos控制台

设置相关配置信息

Alibaba Nacos 学习（二）：Spring Cloud Nacos Config-LMLPHP

启动项目

-- ::14.025  INFO  --- [           main] o.s.c.a.n.c.NacosPropertySourceBuilder   : Loading nacos data, dataId: 'service-provider-test.properties', group: 'DEFAULT_GROUP'

-- ::14.025  INFO  --- [           main] b.c.PropertySourceBootstrapConfiguration : Located property source: CompositePropertySource {name='NACOS', propertySources=[NacosPropertySource {name='service-provider-test.properties'}, NacosPropertySource {name='service-provider.properties'}]}

-- ::14.029  INFO  --- [           main] e.d.example.dockertest.Application       : The following profiles are active: test

-- ::14.043  INFO  --- [           main] ConfigServletWebServerApplicationContext : Refreshing org.springframework.boot.web.servlet.context.AnnotationConfigServletWebServerApplicationContext@22c86919: startup date [Mon Nov  :: CST ]; parent: org.springframework.context.annotation.AnnotationConfigApplicationContext@6aa61224

-- ::14.699  INFO  --- [           main] o.s.cloud.context.scope.GenericScope     : BeanFactory id=0fd1ef74-7ad3-37d4-b602-1ed486ff9aa7

Loading nacos data, dataId: 'service-provider-test.properties'
在Nacos-Server中新建配置，其中Data ID它的定义规则是：${prefix}-${spring.profile.active}.${file-extension}

prefix 默认为 spring.application.name 的值，也可以通过配置项 spring.cloud.nacos.config.prefix 来配置。
spring.profile.active 即为当前环境对应的 profile，可以通过配置项 spring.profile.active 来配置。
file-exetension 为配置内容的数据格式，可以通过配置项 spring.cloud.nacos.config.file-extension 来配置。

测试内容：

Alibaba Nacos 学习（二）：Spring Cloud Nacos Config-LMLPHP

修改内容

-- ::24.525  INFO  --- [.168.50.31_8848] s.c.a.AnnotationConfigApplicationContext : Refreshing org.springframework.context.annotation.AnnotationConfigApplicationContext@4275635b: startup date [Mon Nov  :: CST ]; parent: org.springframework.context.annotation.AnnotationConfigApplicationContext@12381b77

-- ::24.556  INFO  --- [.168.50.31_8848] o.s.boot.SpringApplication               : Started application in 2.611 seconds (JVM running for 855.251)

-- ::24.556  INFO  --- [.168.50.31_8848] s.c.a.AnnotationConfigApplicationContext : Closing org.springframework.context.annotation.AnnotationConfigApplicationContext@4275635b: startup date [Mon Nov  :: CST ]; parent: org.springframework.context.annotation.AnnotationConfigApplicationContext@12381b77

-- ::24.556  INFO  --- [.168.50.31_8848] s.c.a.AnnotationConfigApplicationContext : Closing org.springframework.context.annotation.AnnotationConfigApplicationContext@12381b77: startup date [Mon Nov  :: CST ]; root of context hierarchy

-- ::24.562  INFO  --- [.168.50.31_8848] o.s.c.e.event.RefreshEventListener       : Refresh keys changed: [user.age, user.name]

Refresh keys changed: [user.age, user.name]，没有修改useLocalCache字段，所以不会有刷新纪录。