Oepn Feign

1) Oepn Feign 개념

• Netflix에 의해 처음 만들어진 Declaratic(선언적인) HTTP Client 도구로써, 외부 API 호출을 쉽게할 수 있도록 도와준다.
• 인터테이스와 어노테이션 기반으로 쉽게 작성할 수 있다.

 

2) Open Feign 구현

• 소스 코드 : https://github.com/yewon-Noh/spring-cloud/tree/main/spring-cloud-openfegin/openfeign

dependency 추가

<!-- https://mvnrepository.com/artifact/org.springframework.cloud/spring-cloud-starter-gateway -->
<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-gateway</artifactId>
    <version>4.1.1</version>
</dependency>

 

OpenFeign 활성화

메인 클래스에 @EnableFeignClients 어노테이션을 추가한다.

@SpringBootApplication
@EnableFeignClients
public class OpenfeignApplication {

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

}

 

FeignClient 구현

interface에 @FeignClient 어노테이션을 붙여주면 된다.

@FeignClient(name = "BookClient", url = "${book.client.url}")
public interface BookClient {

    @RequestMapping(method = RequestMethod.GET, value = "/books")
    List<Book> getBooks();

    @RequestMapping(method = RequestMethod.POST, value = "/books/{bookId}", consumes = "application/json")
    Book update(@PathVariable("bookId") Long bookId, Book book);

    // req: MultipartFile, res: JSON
    @RequestMapping(method = RequestMethod.POST
            , value = "/books"
            , consumes = MediaType.MULTIPART_FORM_DATA_VALUE
            , produces = MediaType.APPLICATION_JSON_VALUE)
    List<Book> uploadBooks(@RequestPart(value = "file", required = false) MultipartFile file);

}

 

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참고

• https://mangkyu.tistory.com/278
• https://techblog.woowahan.com/2630/
• https://brightstarit.tistory.com/46