Spring Cloud (6) 分布式配置中心-高可用

高可用

　　现在已经可以从配置中心读取配置文件了，当微服务很多时都从配置中心读取配置文件，这时可以将配置中心做成一个微服务，将其集群化，从而达到高可用。

改造config-server 加入eureka

<?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>    <groupId>com.david</groupId>
    <artifactId>configserver</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>    <name>configserver</name>
    <description>Demo project for Spring Boot</description>    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.5.9.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.8</java.version>
    </properties>    <dependencies>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-eureka</artifactId>
        </dependency>
        <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>    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>Edgware.SR2</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>

并在application.yml中制定服务注册地址：

spring:
  application:
    name: david-config-server
  cloud:
    config:
      server:
        git:
          uri: https://gitee.com/baidawei/SpringCloudConfig.git
          search-paths: repo
          username: 853020304@qq.com
          password: 1z48489w8a
server:
  port: 8888eureka:
  client:
    service-url:
      defaultZone: http://localhost:8761/eureka/

在启动类中增加@EnableDiscoveryClient注解，将config-server注册到eureka

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

启动eureka、config-server

改造config-client

　　将其注册到服务注册中心，作为eureka客户端，需要在pom文件加上eureka依赖：

<?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>    <groupId>com.david</groupId>
    <artifactId>config-client</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>    <name>config-client</name>
    <description>Demo project for Spring Boot</description>    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.5.9.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.8</java.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-eureka</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
    </dependencies>
    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>Edgware.SR2</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>

配置文件bootstrap.yml，加上服务注册中心地址：

spring:
  application:
    name: david-config-client #对应{application}位置
  cloud:
    config:
      #uri: http://localhost:8888/ #配置中心网址
      profile: dev #对应{profile}位置 dev等
      label: master #对应{label}位置 分支
      discovery:
        enabled: true #从配置中心读取文件
        service-id: david-config-server #配置中心的服务名
server:
  port: 8881
eureka:
  client:
    service-url:
      defaultZone: http://localhost:8761/eureka/

启动类 增加注解，用来发现config-server服务，利用其来加载应用配置

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

启动config-client

http://localhost:8881/test 输出dev