微服务SpringCloud之Spring Cloud Config配置中心服务化

 在前面两篇Spring Cloud Config配置中心的博客中都是需要指定配置服务的地址url：spring.cloud.config.uri，客户端都是直接调用配置中心的server端来获取配置文件信息。如果server端要做集群，客户端只能通过原始的方式来路由，server端改变IP地址的时候，客户端也需要修改配置，不符合springcloud服务治理的理念。springcloud提供了这样的解决方案，我们只需要将server端当做一个服务注册到eureka中，client端去eureka中去获取配置中心server端的服务既可。

一、Server端改造

1.添加依赖

在SpringCloudConfigServer项目中，添加spring-cloud-starter-netflix-eureka-client引用。

<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
</dependency>

<?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>2.1.6.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.example</groupId>
    <artifactId>SpringCloudConfigServer</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>war</packaging>
    <name>SpringCloudConfigServer</name>
    <description>Demo project for Spring Boot</description>

    <properties>
        <java.version>1.8</java.version>
        <spring-cloud.version>Greenwich.SR2</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-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-tomcat</artifactId>
            <scope>provided</scope>
        </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>

2.增加了eureka注册中心的配置

在application.properties中增加eureka注册中心的配置，http://localhost:8088是后面启动的eureka server的地址

eureka.client.serviceUrl.defaultZone=http://localhost:8088/eureka/

3.增加注解

在main方法中增加@EnableDiscoveryClient注解

二、客户端改造

1、添加依赖

也是引入spring-cloud-starter-netflix-eureka-client。

<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
</dependency>

<?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>2.1.6.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.example</groupId>
    <artifactId>SpringCloudConfigClient</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>war</packaging>
    <name>SpringCloudConfigClient</name>
    <description>Demo project for Spring Boot</description>

    <properties>
        <java.version>1.8</java.version>
        <spring-cloud.version>Greenwich.SR2</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-config</artifactId>
        </dependency>
<dependency>
  <groupId>org.springframework.boot</groupId>
  <artifactId>spring-boot-starter-actuator</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-tomcat</artifactId>
            <scope>provided</scope>
        </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>

2.配置文件

在bootstrap.properties中去掉指定配置服务的地址url，增加了最后的三个配置：

spring.cloud.config.name=neo-config
spring.cloud.config.profile=dev
spring.cloud.config.label=
spring.cloud.config.discovery.enabled=true
spring.cloud.config.discovery.serviceId=spring-cloud-config-server
eureka.client.serviceUrl.defaultZone=http://localhost:8088/eureka/

spring.cloud.config.discovery.enabled ：开启Config服务发现支持
spring.cloud.config.discovery.serviceId ：指定server端的name,也就是server端spring.application.name的值
eureka.client.serviceUrl.defaultZone ：指向注册中心的地址

3.启动类增加注解

在main方法中增加注解@EnableDiscoveryClient。

三、测试

1.分别启动eureka server、SpringCloudConfigServer、SpringCloudConfigClient。

2.浏览器输入http://localhost:8088/，可以看到注入到eureka server中的服务。

3.输入http://localhost:8001/neo-config/dev，可以看到配置文件的配置信息。

4.输入http://localhost:8002/hello，可以读取到配置文件的属性信息

参考：http://www.ityouknow.com/springcloud/2017/05/25/springcloud-config-eureka.html