搭建注册服务提供者微服务

说明：本次主要完成将Spring Boot应用加入Eureka的服务治理体系(换句话说就是将一个微服务应用向服务注册中心发布自己)

1.修改pom.xml文件(增加Spring Cloud Eureka模块的依赖)

<?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 https://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>2.0.5.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.ml</groupId>
    <artifactId>hello-server</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>hello-server</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.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-eureka</artifactId>
            <version>1.3.4.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
            <exclusions>
                <exclusion>
                    <groupId>org.junit.vintage</groupId>
                    <artifactId>junit-vintage-engine</artifactId>
                </exclusion>
            </exclusions>
        </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.新建HelloController类，创建/hello接口，通过注入DiscoveryClient对象，在日志中打印出服务的相关内容

@RestController
public class HelloController {
    private final Logger logger = LoggerFactory.getLogger(getClass());

    @Autowired
    private DiscoveryClient client;

    @RequestMapping(value = "/hello", method = RequestMethod.GET)
    public String index() {
        List<String> service = client.getServices();
        //System.out.println("services:" + service.get(0));
        logger.info("services:" + service);
        return "hello world";
    }
}

3.在主类中通过加入@EnableDiscoveryClient注解，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EnableDiscoveryClient实例)，才能实现上述Controller中对服务信息的输出。

@SpringBootApplication
@EnableDiscoveryClient
public class HelloServerApplication {

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

4.最后需要在application.properties配置文件中添加以下内容

#配置服务器端口
server.port=1112
#服务命名
spring.application.name=hello-server
#指定服务注册中心地址
eureka.client.serviceurl.defaultZone=http://localhost:1111/eureka/
#ribbon.eureka.enabled=true