Spring Cloud Config provides server-side and client-side support for externalized configuration in a distributed system. With the Config Server, you have a central place to manage external properties for applications across all environments.

Spring Cloud Config 支持服务端与客户端
是一个分布式配置中心
提供配置信息多环境切换
配置信息更新，实时同步

2. 代码实现

2.1 涉及的模块及整体步骤

2.1.1 涉及的模块

config-server：配置中心服务端
config-client：配置中心客户端，验证配置信息访问规则
config-another-client：配置中心客户端，验证配置信息访问规则
config-repository：放置于GitHub的配置

2.1.2 整体步骤

GitHub创建存放配置信息的config-repository目录与配置信息config-client-dev.properties、config-another-client-test.properties，可通过demo中的config-repository模块关联GitHub上的配置。
实现config-server：关键是启动Spring Cloud Config Server功能，指定配置仓库的配置信息
实现config-client：从配置仓库读取配置信息
实现config-another-client：从配置仓库读取配置信息
实现config-repository：放置3、4步骤的配置信息

2.2 源代码

2.2.1 Github地址

https://github.com/andyChenHuaYing/spring-cloud-demo

2.2.2 配置信息地址

配置信息在dev-20180827、与master分支都有，但是代码中使用的是dev-20180827分支的代码，如果想修改值验证，记得确认客户端bootstrap.properties中配置信息与想要访问的仓库地址一致。
https://github.com/andyChenHuaYing/spring-cloud-demo/tree/dev-20180827/config-repository

2.3 config-server

2.3.1 整体实现

pom.xml引入spring-cloud-config-server
application.yml指定配置仓库连接信息
启动类使用注解启动类使用注解@EnableConfigServer开启配置服务功能

2.3.2 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">
    <parent>
        <artifactId>spring-cloud-finchley-demo</artifactId>
        <groupId>org.oscar.scd</groupId>
        <version>1.0.0</version>
    </parent>
    <modelVersion>4.0.0</modelVersion>

    <artifactId>config-server</artifactId>

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

        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-config-server</artifactId>
        </dependency>
    </dependencies>
</project>

2.3.3 application.yml

spring:
  application:
    name: config-server
  cloud:
    config:
      server:
        git:
          uri: https://github.com/andyChenHuaYing/spring-cloud-demo
          searchPaths: config-repository
          username:
          password:
      label: dev-20180827

server:
  port: 8769

2.3.4 ConfigClientApplication

package org.oscar.scd.config.server;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.config.server.EnableConfigServer;

@EnableConfigServer
@SpringBootApplication
public class ConfigServerApplication {

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

2.4 config-client

2.4.1 整体实现

pom.xml文件中引入依赖spring-cloud-starter-config
bootstrap.properties中指定Config Server连接信息以及需要访问配置中心的具体配置信息
ConfigClientApplication常规Spring Boot启动类

2.4.2 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">
    <parent>
        <artifactId>spring-cloud-finchley-demo</artifactId>
        <groupId>org.oscar.scd</groupId>
        <version>1.0.0</version>
    </parent>
    <modelVersion>4.0.0</modelVersion>

    <artifactId>config-client</artifactId>

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

2.4.3 bootstrap.properties

下方信息与配置中心的配置文件的对应关系见后续验证部分

spring.application.name=config-client
spring.cloud.config.label=dev-20180827
spring.cloud.config.profile=dev
spring.cloud.config.uri=http://localhost:8769/
server.port=8770

2.5 config-another-client

与config-client基本一致，区别在于`bootstrap.yml`中的配置信息

2.5.1 整体实现

pom.xml文件中引入依赖spring-cloud-starter-config
bootstrap.properties中指定Config Server连接信息以及需要访问配置中心的具体配置信息
ConfigClientApplication常规Spring Boot启动类

2.5.2 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">
    <parent>
        <artifactId>spring-cloud-finchley-demo</artifactId>
        <groupId>org.oscar.scd</groupId>
        <version>1.0.0</version>
    </parent>
    <modelVersion>4.0.0</modelVersion>

    <artifactId>config-client</artifactId>

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

2.4.3 bootstrap.yml

spring:
  application:
    name: config-another-client
  cloud:
    config:
      label: dev-20180827
      profile: test
      uri: http://localhost:8769/
server:
  port: 8771

2.4.4 ConfigAnotherClientApplication

package org.oscar.scd.config.another.client;

import org.springframework.beans.factory.annotation.Value;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

@RestController
@SpringBootApplication
public class ConfigAnotherClientApplication {

    @Value("${foo}")
    private String foo;

    @RequestMapping("/readFooProp")
    public String readFooProp() {
        return this.foo;
    }


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

2.6 config-repository

保存配置文件

2.6.1 config-client配置文件

config-client-dev.properties

foo=config-client-dev value

2.6.2 config-another-client配置文件

config-another-client-test.properties

foo=config-another-client foo value.

3. 验证

3.1 创建SpringBoot启动类

简单创建Spring Boot启动类即可

3.1.1 ConfigServerApplication

在这里插入图片描述

3.1.2 ConfigClientApplication

参考上一节

3.1.3 ConfigAnotherClientApplication