您好,登錄后才能下訂單哦!
Feign簡介
Feign 是一個聲明web服務客戶端,這便得編寫web服務客戶端更容易,使用Feign 創建一個接口并對它進行注解,它具有可插拔的注解支持包括Feign注解與JAX-RS注解,Feign還支持可插拔的編碼器與解碼器,Spring Cloud 增加了對 Spring MVC的注解,Spring Web 默認使用了HttpMessageConverters, Spring Cloud 集成 Ribbon 和 Eureka 提供的負載均衡的HTTP客戶端 Feign.
聲明式REST客戶端:Feign
先要啟動eureka_register_service工程(注冊中心)和biz-service-0工程(服務生產者)
創建一個maven工程eureka_feign_client
pom.xml
<parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>1.4.3.RELEASE</version> <relativePath/> <!-- lookup parent from repository --> </parent> <properties> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> <java.version>1.8</java.version> </properties> <dependencies> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-feign</artifactId> </dependency> <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>Brixton.SR5</version> <type>pom</type> <scope>import</scope> </dependency> </dependencies> </dependencyManagement>
在應用主類中通過@EnableFeignClients注解開啟Feign功能
啟動文件FeignApplication.java
@SpringBootApplication @EnableDiscoveryClient @EnableFeignClients public class FeignApplication { public static void main(String[] args) { SpringApplication.run(FeignApplication.class, args); } }
定義服務接口類UserClient.java
使用@FeignClient("biz-service-0")注解來綁定該接口對應biz-service-0服務
@FeignClient("biz-service-0") public interface UserClient { @RequestMapping(method = RequestMethod.GET, value = "/getuser") public User getuserinfo(); @RequestMapping(method = RequestMethod.GET, value = "/getuser") public String getuserinfostr(); @RequestMapping(method = RequestMethod.GET, value = "/info") public String info(); }
在web層中調用上面定義的UserController,具體如下
@RestController public class UserController { @Autowired UserClient userClient; @RequestMapping(value = "/getuserinfo", method = RequestMethod.GET) public User getuserinfo() { return userClient.getuserinfo(); } @RequestMapping(value = "/getuserinfostr", method = RequestMethod.GET) public String getuserinfostr() { return userClient.getuserinfostr(); } @RequestMapping(value = "/info", method = RequestMethod.GET) public String info() { return userClient.info(); } }
application.properties配置變量
spring.application.name=feign-consumer server.port=8004 eureka.client.serviceUrl.defaultZone=http://localhost:8000/eureka/
訪問 http://127.0.0.1:8004/getuserinfo
總結:
其實通過Feign封裝了HTTP調用服務方法,使得客戶端像調用本地方法那樣直接調用方法,類似Dubbo中暴露遠程服務的方式,區別在于Dubbo是基于私有二進制協議,而Feign本質上還是個HTTP客戶端
以上就是本文的全部內容,希望對大家的學習有所幫助,也希望大家多多支持億速云。
免責聲明:本站發布的內容(圖片、視頻和文字)以原創、轉載和分享為主,文章觀點不代表本網站立場,如果涉及侵權請聯系站長郵箱:is@yisu.com進行舉報,并提供相關證據,一經查實,將立刻刪除涉嫌侵權內容。