Spring Cloud Eureka 服务发现与消费

服务发现与消费，其服务发现的任务是由Eureka的客户端完成，而服务的消费任务由Ribbon、JerseyClient等完成，Ribbon是一个基于HTTP和TCP的客户端负载均衡器；使用JerseyClient是一个基于HTTP的客户端调用组件，需要需要增加负载均衡器，需要自己来实现，示例代码如下：

创建一个Spring Boot 的基础工程来实现服务消费者，并在pom.xml 中引入必须依赖项 spring-cloud-starter-eureka，引入 spring-cloud-starter-web 来实现Spring MVC 的REST服务进行测试

<?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>org.drsoft.consumer</groupId>

<artifactId>consumer-helloservice</artifactId>

<version>0.0.1-SNAPSHOT</version>

<packaging>jar</packaging>

<name>consumer-helloservice</name>

<description>Demo project for Spring Boot</description>

<parent>

<groupId>org.springframework.boot</groupId>

<artifactId>spring-boot-starter-parent</artifactId>

<version>1.5.6.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>Dalston.SR2</spring-cloud.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.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>
创建应用主类 ConsumerHelloserviceApplication ，通过 @EanbleDiscoveryClient 注解将应用注册为Eureka 客户端应用，以获取服务发现的能力，代码如下：

@EnableDiscoveryClient

@SpringBootApplication

public class ConsumerHelloserviceApplication {

public static void main(String[] args) {

SpringApplication.run(ConsumerHelloserviceApplication.class, args);

}

}
创建 ConsumerController 类，并实现 /consumer 接口，在接口中对服务的调用，这里使用的是服务的名而不是一个具体的地址，服务消费Java代码：

@RestController

public class ConsumerController {

@Autowired

private DiscoveryClient discoveryClient;

@RequestMapping (value = "/consumer", method = RequestMethod.GET)

public String helloConsumer() {

List<ServiceInstance> serviceInstanceList = discoveryClient.getInstances("org.drsoft.webservice.helloservice");

StringBuilder stringBuilder = new StringBuilder();

URI uri = null;

for (ServiceInstance instance : serviceInstanceList) {

stringBuilder.append("host=" + instance.getHost());

stringBuilder.append("port=" + instance.getPort());

stringBuilder.append("serviceId=" + instance.getServiceId());

stringBuilder.append("uri=" + instance.getUri());

stringBuilder.append("\n");

uri = instance.getUri();

}

String uriString = uri.toString() + "/hello/get";

stringBuilder.append("response body=" + new RestTemplate().getForEntity(uriString, String.class).getBody());

return stringBuilder.toString();

}

}
在 application.properties 中配置Eureka 服务注册中心的位置，需要和服务提供者的一致，否则是无法发现服务的，同时设置该消费者的端口号，代码如下：

server.port=8090

spring.application.name=consumer-helloservice

eureka.client.service-url.defaultZone=http://eurekaserver1:1111/eureka/,http://eurekaserver2:1112/eureka
启动consumer-helloservice应用后，我们可以在Eureka信息面板中看到，我们实现的 CONSUMER-HELLOSERVICE 服务，访问地址 http://localhost:8090/consumer 可以看到请求返回内容：

host=192.168.196.187port=8085serviceId=ORG.DRSOFT.WEBSERVICE.HELLOSERVICEuri=http://192.168.196.187:8085 response body=get ok

巴特西

Spring Cloud Eureka 服务发现与消费

最新文章

热门文章