Spring Cloud Ribbon 消費者

新建工程ribbon-consumer，其pom.xml文件如下所示：

<?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>2.2.8.RELEASE</version>
		<relativePath/> <!-- lookup parent from repository -->
	</parent>
	<groupId>com.hangzhou.springcloud</groupId>
	<artifactId>ribbon-consmer</artifactId>
	<version>0.0.1-SNAPSHOT</version>
	<name>ribbon-consmer</name>
	<description>Demo project for Spring Boot</description>

	<properties>
		<java.version>1.8</java.version>
		<spring-cloud.version>Hoxton.SR6</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-ribbon</artifactId>
		</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>

application.properties文件編寫如下：

# 指定運行端口號
server.port=1114
# 指定模塊名稱
spring.application.name=ribbon-consumer

# 註冊到Eureka的註冊中心
eureka.client.register-with-eureka=true
# 獲取註冊實例列表
eureka.client.fetch-registry=true
 # 配置註冊中心地址
eureka.client.service-url.defaultZone=http://localhost:1111/eureka

程序啓動類代碼如下：

@EnableDiscoveryClient
@SpringBootApplication
public class RibbonConsmerApplication {

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

}

ConsumerCofig配置類，編寫如下所示：

@Configuration
public class ConsumerConfig {
	//提供了負載均衡的默認輪詢算法
	@LoadBalanced
	@Bean
	public RestTemplate restTemplate() {
		return new RestTemplate();
	}
}

controller類編寫如下：

@RequestMapping(value="/ribbon")
@RestController
public class RibbonController {
	
	@Autowired
	private RestTemplate restTemplate;
	
	@RequestMapping(value="/index",method=RequestMethod.GET)
	public String index() {
		return restTemplate.getForObject("http://hello-service/test/hello", String.class);
	}

}

啓動eureka-server，再啓動eureka-client，再啓動ribbon-consumer工程，打開遊覽器輸入http://localhost:1114/ribbon/index,效果 如下：