SpringCloud笔记（五）分布式配置中心

ゝ一纸荒年。 2021-12-14 05:41 346阅读 0赞

**目录**

1、搭建远程Git仓库

2、搭建注册中心Eureka Server

3、搭建Config Server

4、测试Config Server是否搭建成功

5、搭建Config Client

6、配置的动态刷新

--------------------

在本文中，将会介绍如何使用SpringCloud+Git搭建一个分布式配置中心。拓扑图如下：

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3pob3VqaWFuX0xpdQ_size_16_color_FFFFFF_t_70][]

(图片来自《SpringCloud微服务实战》)

### 1、搭建远程Git仓库 ###

在Git上面创建一个仓库名为springcloud\_config，并在仓库中创建一个git-config-repo目录，在目录中准备好两个配置文件。liuzhoujian-prd.properties和liuzhoujian-test.properties,这两个配置文件的内容分别是name=liuzhoujian-prd.properties和name=liuzhoujian-test.properties。

**注意：git仓库中文件命名规则如下：\{application\}-\{profile\}.yml或者\{application\}-\{profile\}.properties,这里的\{application\}对应config client的\{spring.application.name\}属性，两者需保持一致！\{profile\}代表不同的环境，有test（测试环境）、prd（生成环境）、pre（预生产环境）、dev（开发环境）等。**

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3pob3VqaWFuX0xpdQ_size_16_color_FFFFFF_t_70 1][]

### 2、搭建注册中心Eureka Server ###

**2.1 pom.xml**

<?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 http://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>2.1.1.RELEASE</version>
            <relativePath/> 
        </parent>
        <groupId>com.lzj</groupId>
        <artifactId>eureka-server</artifactId>
        <version>0.0.1-SNAPSHOT</version>
        <name>eureka-server</name>
        <description>Demo project for Spring Boot</description>
    
        <properties>
            <java.version>1.8</java.version>
            <spring-cloud.version>Greenwich.SR1</spring-cloud.version>
        </properties>
    
        <dependencies>
            
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-starter-netflix-eureka-server</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>
    
        <build>
            <plugins>
                <plugin>
                    <groupId>org.springframework.boot</groupId>
                    <artifactId>spring-boot-maven-plugin</artifactId>
                </plugin>
            </plugins>
        </build>
    
    </project>

**2.2 application.yml**

#微服务项目名称
    spring:
      application:
        name: eureka-server
    server:
      port: 8100
    eureka:
      instance:
        hostname: localhost
      client:
        register-with-eureka: false
        fetch-registry: false
        service-url:
          defaultZone: http://${eureka.instance.hostname}:${server.port}/eureka
      #测试时：关闭eureka server的自我保护机制，保证不可用服务及时剔除
      server:
        enable-self-preservation: false

**2.3 启动类**

@SpringBootApplication
    @EnableEurekaServer //表示这是注册中心
    public class EurekaServerApplication {
        public static void main(String[] args) {
            SpringApplication.run(EurekaServerApplication.class, args);
        }
    }

### 3、搭建Config Server ###

**3.1pom.xml**

<?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 http://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>2.1.1.RELEASE</version>
            <relativePath/> 
        </parent>
        <groupId>com.lzj</groupId>
        <artifactId>config-server</artifactId>
        <version>0.0.1-SNAPSHOT</version>
        <name>config-server</name>
        <description>Demo project for Spring Boot</description>
    
        <properties>
            <java.version>1.8</java.version>
            <spring-cloud.version>Greenwich.SR1</spring-cloud.version>
        </properties>
    
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-config-server</artifactId>
            </dependency>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
            </dependency>
    
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-test</artifactId>
                <scope>test</scope>
            </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>
    
        <build>
            <plugins>
                <plugin>
                    <groupId>org.springframework.boot</groupId>
                    <artifactId>spring-boot-maven-plugin</artifactId>
                </plugin>
            </plugins>
        </build>
    
    </project>

**3.2application.yml**

spring:
      application:
        name: config-server
    
      cloud:
        config:
          server:
            git:
              ##git 仓库的地址
              uri: https://gitee.com/liuzhoujian/springcloud_config.git
              ##检索的仓库下的目录名称，多个仓库可以以逗号分隔
              search-paths: git-repo-config
          ##版本
          label: master
    
    server:
      port: 9090
    
    
    ##将config server注册到注册中心
    eureka:
      client:
        service-url:
          defaultZone: http://localhost:8100/eureka

>     如果我们的Git仓库需要权限访问，那么可以通过配置下面的两个属性来实现；
>     spring.cloud.config.server.git.username：访问Git仓库的用户名
>     spring.cloud.config.server.git.password：访问Git仓库的用户密码

**3.3启动类**

@SpringBootApplication
    @EnableConfigServer
    public class ConfigServerApplication {
    
        public static void main(String[] args) {
            SpringApplication.run(ConfigServerApplication.class, args);
        }
    }

### 4、测试Config Server是否搭建成功 ###

4.1先启动eureka server注册中心，之后再启动Config Server。查看eureka注册中心，可以看到Config Server已经被注册。

![20190708114749689.png][]

4.2接着访问Config Server, 访问的URL与配置文件映射关系如下：

/{application}/{profile}[/{label}]
    /{application}-{profile}.yml
    /{label}/{application}-{profile}.yml
    /{application}-{profile}.properties
    /{label}/{application}-{profile}.properties

使用浏览器访问：http://localhost:9090/liuzhoujian/test 或者 http://localhost:9090/liuzhoujian-test.properties

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3pob3VqaWFuX0xpdQ_size_16_color_FFFFFF_t_70 2][]

至此，Config Server就搭建成功了。

### 5、搭建Config Client ###

**5.1 pom.xml**

<?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 http://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>2.1.1.RELEASE</version>
            <relativePath/> 
        </parent>
        <groupId>com.lzj</groupId>
        <artifactId>config-client</artifactId>
        <version>0.0.1-SNAPSHOT</version>
        <name>config-client</name>
        <description>Demo project for Spring Boot</description>
    
        <properties>
            <java.version>1.8</java.version>
            <spring-cloud.version>Greenwich.SR1</spring-cloud.version>
        </properties>
    
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-starter-config</artifactId>
            </dependency>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
            </dependency>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-web</artifactId>
            </dependency>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-actuator</artifactId>
            </dependency>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-test</artifactId>
                <scope>test</scope>
            </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>
    
        <build>
            <plugins>
                <plugin>
                    <groupId>org.springframework.boot</groupId>
                    <artifactId>spring-boot-maven-plugin</artifactId>
                </plugin>
            </plugins>
        </build>
    
    </project>

**5.2 bootstrap.yml(注意：若config server的端口不是8888，则config client需要创建名为bootstrap.yml的配置文件)**

##spring.application.name的值对应git仓库文件名{application}-{profile}.properties中的{application}
    spring:
      application:
        name: liuzhoujian
      cloud:
        config:
          ##对应git文件中的{profile}
          profile: test
          discovery:
            ##对应config-server的spring.application.name的值
            service-id: config-server
            enabled: true
          label: master
    eureka:
      client:
        service-url:
          defaultZone: http://localhost:8100/eureka
    
    server:
      port: 9091

**5.3 controller**

@RestController
    public class ConfigClientController {
    
        @Value("${name}")
        private String name;
    
        @GetMapping("/name")
        public String name() {
            return this.name;
        }
    }

**5.4 启动类**

@SpringBootApplication
    @EnableDiscoveryClient
    public class ConfigClientApplication {
        public static void main(String[] args) {
            SpringApplication.run(ConfigClientApplication.class, args);
        }
    }

启动config-client,再访问config-client的接口，http://localhost:9091/name，可以看到name属性的值从远端git仓库的配置文件中已经成功取得！

![2019070819163429.png][]

### 6、配置的动态刷新 ###

在上面搭建的分布式配置中心，当人为修改Git中的配置文件时，在config-client端并不能感知到，因为config-client首次是从config-server获取数据并缓存在本地，以后就直接从缓存中获取数据，无法更新最新的git配置文件。

**解决方法：**

**6.1 添加actuator依赖：**

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

**6.2 在bootstrap.xml中添加配置：**

management:
      endpoints:
        web:
          exposure:
            include: "*"

**6.3 在controller上添加注解：@RefreshScope**

![20190708193319500.png][]

当人为修改Git中的配置文件时，需要手动发送POST请求进行刷新：

>     http://127.0.0.1:9091/actuator/refresh

**6.4 验证**

首先访问config-client客户端，获取配置文件信息为liuzhoujian-test.properties

![20190708194012353.png][]

在git仓库修改name=liuzhoujian-test.properties111

![20190708194118104.png][]

通过postman调用接口刷新配置

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3pob3VqaWFuX0xpdQ_size_16_color_FFFFFF_t_70 3][]

再次访问config-client客户端：

![2019070819464543.png][]

可以看到配置已经刷新！

文章参考：《springcloud微服务实战》

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