refactor : 게시글 클라이언트 컴포넌트 value 변경 및 주석 추가

놀이터(예제 코드 작성)/spring-cloud-open-feign/README.md

@@ -22,3 +22,4 @@
 - [GitHub - OpenFeign/feign](https://github.com/OpenFeign/feign)
 - [Java Jackson JSON Library](https://kwonnam.pe.kr/wiki/java/jackson)
 - [{JSON} Placeholder](https://jsonplaceholder.typicode.com/)
+- [Spring Cloud Openfeign](https://brunch.co.kr/@springboot/202)

놀이터(예제 코드 작성)/spring-cloud-open-feign/src/main/kotlin/com/banjjoknim/springcloudopenfeign/domain/PostClient.kt

@@ -4,6 +4,19 @@ import org.springframework.cloud.openfeign.FeignClient
 import org.springframework.web.bind.annotation.GetMapping
 import org.springframework.web.bind.annotation.PathVariable
 
+/**
+ * Feign is a declarative web service client. It makes writing web service clients easier.
+ * To use Feign create an interface and annotate it.
+ * It has pluggable annotation support including Feign annotations and JAX-RS annotations.
+ * Feign also supports pluggable encoders and decoders.
+ * Spring Cloud adds support for Spring MVC annotations and for using the same HttpMessageConverters used by default in Spring Web.
+ * Spring Cloud integrates Eureka, as well as Spring Cloud LoadBalancer to provide a load-balanced http client when using Feign.
+ *
+ * 쉽게 말하면 RestTemplate, RestClient 등의 `HTTP Client`를 어노테이션으로 선언하여 사용하는 것이라 생각하면 된다.
+ * 인터페이스를 만들고 @FeignClient 를 선언하기만 하면 구현체는 런타임에 알아서 만들어진다.
+ *
+ * @see org.springframework.cloud.openfeign.FeignClient
+ */
 @FeignClient(value = "post", url = "https://jsonplaceholder.typicode.com/")
 interface PostClient {