SpringCloud教程第6篇：config（F版本）

一、簡介

在分散式系統中，由於服務數量巨多，為了方便服務配置文件統一管理，實時更新，所以需要分散式配置中心組件。在Spring Cloud中，有分散式配置中心組件spring cloud config ，它支援配置服務放在配置服務的記憶體中（即本地），也支援放在遠程Git倉庫中。在spring cloud config 組件中，分兩個角色，一是config server，二是config client。

二、構建Config Server

pom

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="//maven.apache.org/POM/4.0.0"
         xmlns:xsi="//www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="//maven.apache.org/POM/4.0.0 //maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.forezp</groupId>
    <artifactId>sc-f-chapter6</artifactId>
    <version>1.0-SNAPSHOT</version>


    <modules>
        <module>config-server</module>
        <module>config-client</module>
    </modules>

    <name>sc-f-chapter6</name>
    <description>Demo project for Spring Boot</description>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0.3.RELEASE</version>
        <relativePath/>
    </parent>


    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.8</java.version>
        <spring-cloud.version>Finchley.RELEASE</spring-cloud.version>
    </properties>

    <dependencies>
        <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>

創建一個spring-boot項目，取名為config-server,其pom.xml如下：

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="//maven.apache.org/POM/4.0.0" xmlns:xsi="//www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="//maven.apache.org/POM/4.0.0 //maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>com.forezp</groupId>
    <artifactId>config-server</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>config-server</name>
    <description>Demo project for Spring Boot</description>


    <parent>
        <groupId>com.forezp</groupId>
        <artifactId>sc-f-chapter6</artifactId>
        <version>1.0-SNAPSHOT</version>
    </parent>

    <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>com.forezp</groupId>
            <artifactId>sc-f-chapter6</artifactId>
            <version>1.0-SNAPSHOT</version>
        </dependency>
        <dependency>
            <groupId>com.forezp</groupId>
            <artifactId>sc-f-chapter6</artifactId>
            <version>1.0-SNAPSHOT</version>
        </dependency>
    </dependencies>
    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>


</project>

在程式的入口Application類加上@EnableConfigServer註解開啟配置伺服器的功能，程式碼如下：

package com.forezp.configserver;

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

@SpringBootApplication
@EnableConfigServer
public class ConfigServerApplication {

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

}

需要在程式的配置文件application.properties文件配置以下：

spring.application.name=config-server
server.port=8888

spring.cloud.config.server.git.uri=//github.com/CMRcircle/SpringcloudConfig/（這裡換成你自己的倉庫地址）
spring.cloud.config.server.git.searchPaths=respos（你倉庫文件夾）
spring.cloud.config.label=master（你的分支）
spring.cloud.config.server.git.username=你的用戶名
spring.cloud.config.server.git.password=你的密碼

spring.cloud.config.server.git.uri：配置git倉庫地址
spring.cloud.config.server.git.searchPaths：配置倉庫路徑
spring.cloud.config.label：配置倉庫的分支
spring.cloud.config.server.git.username：訪問git倉庫的用戶名
spring.cloud.config.server.git.password：訪問git倉庫的用戶密碼

如果Git倉庫為公開倉庫，可以不填寫用戶名和密碼，如果是私有倉庫需要填寫

foo = foo version 3

啟動程式：訪問//localhost:8888/foo/dev

{"name":"foo","profiles":["dev"],"label":null,"version":"cfe66eaea0ad0e7efc39a12669884597d045c796","state":null,"propertySources":[]}

證明配置服務中心可以從遠程程式獲取配置資訊。

http請求地址和資源文件映射如下:

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

三、構建一個config client、

重新創建一個springboot項目，取名為config-client,其pom文件：

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="//maven.apache.org/POM/4.0.0" xmlns:xsi="//www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="//maven.apache.org/POM/4.0.0 //maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.forezp</groupId>
    <artifactId>config-client</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>config-client</name>
    <description>Demo project for Spring Boot</description>
    <parent>
        <groupId>com.forezp</groupId>
        <artifactId>sc-f-chapter6</artifactId>
        <version>1.0-SNAPSHOT</version>
    </parent>

    <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>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>


</project>

其配置文件bootstrap.properties：

spring.application.name=config-client
spring.cloud.config.label=master
spring.cloud.config.profile=dev
spring.cloud.config.uri= //localhost:8888/
server.port=8881

spring.cloud.config.label 指明遠程倉庫的分支
spring.cloud.config.profile
- dev開發環境配置文件
- test測試環境
- pro正式環境
spring.cloud.config.uri= //localhost:8888/ 指明配置服務中心的網址。

程式的入口類，寫一個API介面「／hi」，返回從配置中心讀取的foo變數的值，程式碼如下：

package com.forezp.configclient;

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;

@SpringBootApplication
@RestController
public class ConfigClientApplication {

    public static void main(String[] args) {
        SpringApplication.run(ConfigClientApplication.class, args);
    }
    @Value("${foo}")
    String foo;
    @RequestMapping(value = "/hi")
    public String hi(){
        return foo;
    }

}

打開網址訪問：//localhost:8881/hi，網頁顯示：

foo version 3

這就說明，config-client從config-server獲取了foo的屬性，而config-server是從git倉庫讀取的,如圖：

源碼：//github.com/CMRcircle/learnspringcloud/tree/master/sc-f-chapter6

Tags: 《史上最簡單的Spring Cloud教程》筆記 SpringCloud