javascript
Spring Cloud (3) 服务消费者-Ribbon
在上一篇中使用LoadBalancerClient接口實(shí)現(xiàn)了獲取某個(gè)服務(wù)的具體實(shí)例,并根據(jù)實(shí)例信息發(fā)起服務(wù)接口消費(fèi)請(qǐng)求。但是這樣的做法需要我們手工的區(qū)編寫服務(wù)選取、連接拼接等繁瑣的工作,對(duì)于開發(fā)人員來(lái)說(shuō)非常不友好。所以使用Spring Cloud中針對(duì)客戶端負(fù)載均衡的工具包:Spring Cloud Ribbon.
?
Spring Cloud Ribbon
Spring Cloud Ribbon是基于Netflix Ribbon實(shí)現(xiàn)的一套客戶端負(fù)載均衡的工具。他是一個(gè)基于Http和TCP的哭護(hù)短負(fù)載均衡器。他可以通過(guò)在客戶端中配置ribbonServerList來(lái)設(shè)置服務(wù)端列表去輪詢?cè)L問(wèn)以達(dá)到負(fù)載均衡的作用。
當(dāng)Ribbon與Eureka聯(lián)合使用時(shí),ribbonServerList會(huì)被DiscoveryEnabledNIWSServerList重寫,擴(kuò)展成從Eureka注冊(cè)中心中獲取服務(wù)實(shí)例列表。同事它也會(huì)用NIWSDiscoveryPing來(lái)取代IPing,它將職責(zé)委托給Eureka來(lái)確定服務(wù)端是否已經(jīng)啟動(dòng)。
?
新建com.david.ribbon項(xiàng)目,在pom.xml中增加下面的依賴:
<?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>ribbon</artifactId><version>0.0.1-SNAPSHOT</version><packaging>jar</packaging><name>ribbon</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-starter-ribbon</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>編輯application.yml配置文件:
server:port: 8764 spring:application:name: david-ribbon eureka:client:service-url:default-zone: http://localhost:8761/eureka/在工程的啟動(dòng)類中,通過(guò)@EnbaleDiscoveryClient向服務(wù)中心注冊(cè),并向ioc注入bean,并通過(guò)@LoadBalanced注解表明這是一個(gè)restTemplate開啟負(fù)載均衡的功能。
@EnableDiscoveryClient @SpringBootApplication public class RibbonApplication {@Bean@LoadBalanced //開啟負(fù)載均衡 RestTemplate restTemplate(){return new RestTemplate();}public static void main(String[] args) {SpringApplication.run(RibbonApplication.class, args);} }新建TestController
@RestController public class TestController {@AutowiredRestTemplate restTemplate;@GetMapping("/consumer2")public String test(){return restTemplate.getForObject("http://david-eureka-client/test",String.class);}}注意這里我們沒(méi)有使用原來(lái)的LoadBalancerClient相關(guān)邏輯外,對(duì)RestTemplate的使用,我們第一個(gè)url參數(shù)是服務(wù)名,Spring Cloud Ribbon 有一個(gè)攔截器,它能夠在這里進(jìn)行實(shí)際調(diào)用的時(shí)候,自動(dòng)去選取服務(wù)實(shí)例,并將實(shí)際要請(qǐng)求的IP地址和端口替換這里的服務(wù)名,從而完成服務(wù)接口的調(diào)用。
啟動(dòng)項(xiàng)目:http://localhost:8764/consumer2
?
項(xiàng)目結(jié)構(gòu):
?
轉(zhuǎn)載于:https://www.cnblogs.com/baidawei/p/9139828.html
總結(jié)
以上是生活随笔為你收集整理的Spring Cloud (3) 服务消费者-Ribbon的全部?jī)?nèi)容,希望文章能夠幫你解決所遇到的問(wèn)題。
- 上一篇: 6.4高级查询:分组查询 链接查询 子查
- 下一篇: jQuery - focusin/foc