Springboot 整合 SpringCloud组件-Config 配置中心 ConfigClient (七)-蒲公英云

在上一篇https://blog.csdn.net/qq_35387940/article/details/94616604 我们已经将配置中心 ConfigServer成功完成整合，也和github打通，那么这篇我们将实现ConfigClient ，通过 ConfigServer去读取github里的相关值。

大致流程如下图：

Azure (2).png

不多说，我们开始整合，创建一个springboot项目，起名config-client:

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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>2.1.6.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.cloud</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>Finchley.RELEASE</spring-cloud.version>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-config</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</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>

接着我们写一个controller，写一个接口来测试读取GitHub的配置文件值，ConfigClientController.java：

import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
@RestController
public class ConfigClientController {
    @Value("${testValue}")
    String testValue;
    @RequestMapping(value = "/getTestValue")
    public String getTestValue(){
        return "获取到的配置文件值为："+testValue;
    }
}

然后是配置文件，这里我们需要创建一个bootstrap.yml (或者bootstrap.properties)：

eureka:
  instance:
#以IP地址注册到服务中心，相互注册使用IP地址
    preferIpAddress: true
    instance-id: ${spring.cloud.client.ip-address}:${server.port}
  client:
    serviceUrl:
      defaultZone: http://localhost:8761/eureka/
spring:
  application:
#和git里的文件名（application）对应
    name: config-client
  cloud:
    config:
#分支
      label: master
#环境值
      profile: dev
#config-server的地址
      uri: http://localhost:8888/
server:
  port: 8881

在启动类加上注解，也将这个服务注册到Eureka注册中心去：

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.eureka.EnableEurekaClient;
@EnableEurekaClient
@SpringBootApplication
public class ConfigClientApplication {
    public static void main(String[] args) {
        SpringApplication.run(ConfigClientApplication.class, args);
    }
}

OK，到这里已经准备完毕，将config-client服务也跑起来，

访问http://localhost:8881/getTestValue ：

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OK，git上面的配置值成功获取。

PS：补充2个错误，项目无法正常运行

一、如果你在运行项目出现以下这类错误：

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'configClientController': Injection of autowired dependencies failed; nested exception is java.lang.IllegalArgumentException: Could not resolve placeholder 'testValue' in value "${testValue}"

不用想，你的config-client 已经在项目跑起来尝试地去访问config-server，然后尝试读取git里面的值，发现找不到才报的错。

那么怎么解决， 1.请对比配置文件里面有没有这个配置项的key 2.请对照好git里面配置文件的名字是不是跟我们这个项目里的服务名一致. 3.config-server服务有没有正常运行，端口是不是对应起来了 4.这个服务用的配置文件是bootstrap.yml，优先级大于application.yml，有没有配置信息搞乱了。

二、如果你在运行项目出现以下这类错误：

2019-07-04 15:36:46.738  INFO 16380 --- [      Thread-15] com.netflix.discovery.DiscoveryClient    : Shutting down DiscoveryClient ...
2019-07-04 15:36:46.752  INFO 16380 --- [nfoReplicator-0] com.netflix.discovery.DiscoveryClient    : DiscoveryClient_CLIENT-TEST/192.168.2.246:8881 - registration status: 204
2019-07-04 15:36:46.753  INFO 16380 --- [nfoReplicator-0] com.netflix.discovery.DiscoveryClient    : DiscoveryClient_CLIENT-TEST/192.168.2.246:8881: registering service...
2019-07-04 15:36:46.756  INFO 16380 --- [nfoReplicator-0] com.netflix.discovery.DiscoveryClient    : DiscoveryClient_CLIENT-TEST/192.168.2.246:8881 - registration status: 204
2019-07-04 15:36:46.756  INFO 16380 --- [      Thread-15] com.netflix.discovery.DiscoveryClient    : Unregistering ...
2019-07-04 15:36:46.761  INFO 16380 --- [      Thread-15] com.netflix.discovery.DiscoveryClient    : DiscoveryClient_CLIENT-TEST/192.168.2.246:8881 - deregister  status: 200
2019-07-04 15:36:46.769  INFO 16380 --- [      Thread-15] com.netflix.discovery.DiscoveryClient    : Completed shut down of DiscoveryClient