springcloud-eureka简单实现
请参考 spring+cloud为服务实战 第三章
一。创建Eureka服务
1.使用Idea创建一个项目
结构如下：
2.pom.xml配置:
<?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.cloudlearn</groupId>
<artifactId>core</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging>
<name>core</name>
<description>Demo project for Spring Boot</description>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.0.6.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>
<spring-cloud.version>Finchley.SR1</spring-cloud.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-eureka-server</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>${spring-cloud.version}</version>
<type>pom</type>
<scope>import</scope>
</dependency>
</dependencies>
</dependencyManagement>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>
3.启动类配置
/*通过@EnableEurekaServer注解启动一个服务注册中心，提供给其他应用进行对话
* 默认情况下服务注册中心也会将自己作为客户端尝试注册自己，所以我们应该禁止，只需在配置文件中修改即可（application.properties有详细说明）:
* eureka.client.register-with-eureka=false
* eureka.client.fetch-registry=false
* */
@EnableEurekaServer
@SpringBootApplication
public class CoreApplication {
public static void main(String[] args) {
SpringApplication.run(CoreApplication.class, args);
}
}
4.application.properties配置
server.port=1111
eureka.instance.hostname=localhost
#由于该应用未注册中心，所以设置为false,代表不向注册中心注册自己
eureka.client.register-with-eureka=false
#由于注册中心的职责就是维护实例，所以它并不需要去检索服务，所以设置成false
eureka.client.fetch-registry=false
eureka.client.service-url.defaultZone=http://${eureka.instance.hostname}:${server.port}/eureka
5.运行一下我们的项目 并且访问 http://localhost:1111/ 结果如下：
因为以上只是开启了服务注册中心，所以还没有服务，下面我们在创建一个注册服务
二。注册服务
1.创建过程与上面类似只是选择服务那里有些许不同（web项目）
2.pom.xml配置：
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.cloudlearn</groupId>
<artifactId>zhuce</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging>
<name>zhuce</name>
<description>Demo project for Spring Boot</description>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.0.6.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
<java.version>1.8</java.version>
<spring-cloud.version>Finchley.SR1</spring-cloud.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-eureka-server</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<!-- https://mvnrepository.com/artifact/log4j/log4j -->
<dependency>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
<version>1.2.17</version>
</dependency>
</dependencies>
<dependencyManagement>
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-dependencies</artifactId>
<version>${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>
3.启动类配置
@RestController
public class HelloController {
private final static org.apache.log4j.Logger log = org.apache.log4j.Logger.getLogger(HelloController.class);
@Autowired
private DiscoveryClient discoveryClient;
@RequestMapping("/hello")
public String Hello(){
discoveryClient.getServices().forEach(id -> {
discoveryClient.getInstances(id).forEach(instance -> {
log.info("/hello, host:" + instance.getHost() + ", service_id:" + instance.getServiceId());
});
});
return "Hello World";
}
}
//通过添加注解EnableDiscoveryClient，激活Eureka中的DiscoveryClient实现（自动化配置，创建DiscoveryClient接口针对Eureka客户端的EurekaDiscoveryClient实例）
@EnableDiscoveryClient
@SpringBootApplication
public class ZhuceApplication {
public static void main(String[] args) {
SpringApplication.run(ZhuceApplication.class, args);
}
}
4.application.properties配置：
#服务的名称
spring.application.name=hello-service
#指定服务中心的地址（我们上一个服务中心的地址） eureka.client.service-url.defaultZone=http://localhost:1111/eureka/
5.启动我们的项目，结果如下代表启动成功
然后在运行 http://localhost:1111/ 结果如下：
运行http://localhost:8080/hello，结果控制台日志打印：
