[feat] 게시물 좋아요 기능 구현

src/main/java/wanted/media/exception/CustomException.java

@@ -0,0 +1,15 @@
+package wanted.media.exception;
+
+import lombok.Getter;
+
+@Getter
+public class CustomException extends RuntimeException {
+    private final ErrorCode errorCode;
+    private String customMessage;
+
+    public CustomException(ErrorCode errorCode) {
+        super(errorCode.getMessage());
+        this.errorCode = errorCode;
+        this.customMessage = errorCode.getMessage();
+    }
+}

src/main/java/wanted/media/exception/ErrorCode.java

@@ -1,16 +1,17 @@
 package wanted.media.exception;
 
-import org.springframework.http.HttpStatus;
-
 import lombok.Getter;
 import lombok.RequiredArgsConstructor;
+import org.springframework.http.HttpStatus;
 
 @Getter
 @RequiredArgsConstructor
 public enum ErrorCode {
-	ENTITY_NOT_FOUND(HttpStatus.NOT_FOUND, "존재하지 않는 엔티티입니다."),
-	INVALID_PARAMETER(HttpStatus.BAD_REQUEST, "잘못된 요청입니다.");
+    ENTITY_NOT_FOUND(HttpStatus.NOT_FOUND, "존재하지 않는 엔티티입니다."),
+    // 클라이언트의 입력 값에 대한 일반적인 오류 (@PathVariable, @RequestParam가 잘못되었을 때)
+    INVALID_INPUT_VALUE(HttpStatus.BAD_REQUEST, "클라이언트의 입력 값을 확인해주세요."),
+  	INVALID_PARAMETER(HttpStatus.BAD_REQUEST, "잘못된 요청입니다.");
 
-	private final HttpStatus status;
-	private final String message;
+    private final HttpStatus status;
+    private final String message;
 }

src/main/java/wanted/media/exception/handler/GlobalExceptionHandler.java

@@ -5,6 +5,7 @@
 import org.springframework.http.ResponseEntity;
 import org.springframework.web.bind.annotation.ExceptionHandler;
 import org.springframework.web.bind.annotation.RestControllerAdvice;
+import wanted.media.exception.CustomException;
 import wanted.media.exception.ErrorCode;
 import wanted.media.exception.ErrorResponse;
 import wanted.media.exception.NotFoundException;
@@ -17,7 +18,7 @@ public ResponseEntity<ErrorResponse> handleBadRequestException(BadRequestExcepti
         return ResponseEntity.badRequest()
                 .body(new ErrorResponse(400, e.getMessage()));
     }
-
+  
     @ExceptionHandler(NotFoundException.class)
     public ResponseEntity<ErrorResponse> handlePostNotFound(NotFoundException e) {
         ErrorCode errorCode = e.getErrorCode();
@@ -27,4 +28,11 @@ public ResponseEntity<ErrorResponse> handlePostNotFound(NotFoundException e) {
         );
         return ResponseEntity.status(HttpStatus.NOT_FOUND).body(errorResponse);
     }
+
+    @ExceptionHandler(CustomException.class)
+    protected ResponseEntity<ErrorResponse> handleCustomException(final CustomException e) {
+        return ResponseEntity
+                .status(e.getErrorCode().getStatus().value())
+                .body(new ErrorResponse(e.getErrorCode().getStatus().value(), e.getCustomMessage()));
+    }
 }

src/main/java/wanted/media/post/controller/PostController.java

@@ -4,17 +4,21 @@
 import org.springframework.http.ResponseEntity;
 import org.springframework.web.bind.annotation.GetMapping;
 import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.bind.annotation.PostMapping;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RestController;
 import wanted.media.post.domain.Post;
 import wanted.media.post.dto.PostDetailResponse;
+import wanted.media.post.dto.PostIdResponse;
 import wanted.media.post.service.PostService;
 
+import java.util.HashMap;
+import java.util.Map;
+
 @RestController
 @RequestMapping("/api/posts")
 @RequiredArgsConstructor
 public class PostController {
-
     private final PostService posetService;
 
     /**
@@ -41,4 +45,16 @@ public ResponseEntity<PostDetailResponse> getPost(@PathVariable String postId) {
                 .build();
         return ResponseEntity.ok(result);
     }
+
+    @PostMapping("/likes/{postId}")
+    public ResponseEntity<?> getLikes(@PathVariable(name = "postId") String postId) {
+        try {
+            String id = postService.increaseLike(postId);
+            return ResponseEntity.ok().body(new PostIdResponse<>(id, "좋아요 수 증가 완료"));
+        } catch (Exception e) {
+            Map<String, String> errorMessage = new HashMap<>();
+            errorMessage.put("좋아요 수 증가 실패", e.getMessage());
+            return ResponseEntity.internalServerError().body(new PostIdResponse<>(postId, errorMessage));
+        }
+    }
 }

src/main/java/wanted/media/post/domain/Post.java

@@ -1,6 +1,7 @@
 package wanted.media.post.domain;
 
 import jakarta.persistence.*;
+import jakarta.validation.constraints.NotNull;
 import jakarta.validation.constraints.Size;
 import lombok.*;
 import org.hibernate.annotations.ColumnDefault;
@@ -32,6 +33,7 @@ public class Post {
     private String title;
 
     private String content;
+
     private String hashtags;
 
     @ColumnDefault("0")
@@ -59,4 +61,8 @@ public void incrementViewCount() {
         }
         this.viewCount += 1;
     }
+
+    public void addLikeCount() {
+        this.likeCount++;
+    }
 }

src/main/java/wanted/media/post/dto/PostIdResponse.java

@@ -0,0 +1,11 @@
+package wanted.media.post.dto;
+
+import lombok.AllArgsConstructor;
+import lombok.Getter;
+
+@Getter
+@AllArgsConstructor
+public class PostIdResponse<T> {
+    private final String postId;
+    private final T messgae;
+}

src/main/java/wanted/media/post/service/PostService.java

@@ -3,6 +3,7 @@
 import lombok.RequiredArgsConstructor;
 import org.springframework.stereotype.Service;
 import org.springframework.transaction.annotation.Transactional;
+import wanted.media.exception.CustomException;
 import wanted.media.exception.ErrorCode;
 import wanted.media.exception.NotFoundException;
 import wanted.media.post.domain.Post;
@@ -12,7 +13,7 @@
 @RequiredArgsConstructor
 public class PostService {
     private final PostRepository postRepository;
-
+  
     @Transactional
     public Post getPost(String postId) {
         Post post = postRepository.findById(postId)
@@ -21,4 +22,49 @@ public Post getPost(String postId) {
         post.incrementViewCount();
         return post;
     }
+
+    @Transactional
+    public String increaseLike(String postId) {
+        if (postId == null) {
+            new CustomException(ErrorCode.INVALID_INPUT_VALUE);
+        }
+
+        // contentId를 통해 게시물의 SNS 유형 조회
+        Post post = postRepository.findById(postId).orElseThrow(() -> new CustomException(ErrorCode.ENTITY_NOT_FOUND));
+
+        String snsType = post.getType().name();
+        // 외부 SNS API 호출 부분 (기능 개발을 위한 요소로, 실제 동작하지 않음)
+        snsApi(snsType, postId);
+
+        // 좋아요 수 증가
+        post.addLikeCount();
+        return postId;
+    }
+
+    // 외부 SNS API 호출 부분 (기능 개발을 위한 요소로, 실제 동작하지 않음)
+    public void snsApi(String snsType, String postId) {
+        String endpoint = "";
+
+        // SNS 유형에 따른 외부 엔드포인트 구성
+        switch (snsType.toLowerCase()) {
+            case "facebook":
+                endpoint = "https://www.facebook.com/likes/" + postId;
+                break;
+            case "twitter":
+                endpoint = "https://www.twitter.com/likes/" + postId;
+                break;
+            case "instagram":
+                endpoint = "https://www.instagram.com/likes/" + postId;
+                break;
+            case "threads":
+                endpoint = "https://www.threads.net/likes/" + postId;
+                break;
+            default:
+                endpoint = null;
+        }
+
+        // 요구사항 시나리오에 따라 필요하지만 실제 동작하지 않기에 주석 처리함
+//        RestTemplate restTemplate = new RestTemplate();
+//        String response = restTemplate.postForObject(endpoint, null, String.class);
+    }
 }