[BE] [REFACTOR] 논문 집권호 데이터 형식 수정 및 게시글 등록일 필드 추가

backend/src/main/java/org/example/backend/board/domain/dto/BoardResDto.java

@@ -7,6 +7,7 @@
 import lombok.Getter;
 import lombok.NoArgsConstructor;
 import org.example.backend.board.domain.entity.Board;
+import org.example.backend.common.utils.TimeParsingUtils;
 
 @Getter
 @NoArgsConstructor(access = AccessLevel.PROTECTED)
@@ -16,18 +17,20 @@ public class BoardResDto {
     private String content;
     private String writer;
     private List<String> fileList;
-    private LocalDateTime createDate;
+    private String createDate;
+    private int viewCount;
     private String category;
 
     @Builder
     private BoardResDto(Long id, String title, String content, String writer,
-                        List<String> fileList, LocalDateTime createDate, String category) {
+                        List<String> fileList, String createDate, int viewCount, String category) {
         this.id = id;
         this.title = title;
         this.content = content;
         this.writer = writer;
         this.fileList = fileList;
         this.createDate = createDate;
+        this.viewCount = viewCount;
         this.category = category;
     }
 
@@ -38,7 +41,8 @@ public static BoardResDto of(Board board) {
                 .content(board.getContent())
                 .writer(board.getWriter())
                 .fileList(board.getFileList())
-                .createDate(board.getCreatedDateTime())
+                .createDate(TimeParsingUtils.toRelativeTimeFormat(board.getCreatedDateTime()))
+                .viewCount(board.getViewCount())
                 .category(board.getCategory().name())
                 .build();
     }

backend/src/main/java/org/example/backend/board/domain/entity/Board.java

@@ -37,7 +37,7 @@ public class Board extends BaseEntity {
     @Column(name = "file_list", length = 1000)
     private List<String> fileList;
 
-    @Column(name = "created_date_time")
+    @Column(name = "created_date")
     private LocalDateTime createdDateTime;
 
     @Enumerated(EnumType.STRING)

backend/src/main/java/org/example/backend/common/utils/TimeParsingUtils.java

@@ -2,8 +2,14 @@
 
 import java.time.LocalDateTime;
 import java.time.format.DateTimeFormatter;
+import java.time.temporal.ChronoUnit;
 
 public class TimeParsingUtils {
+    private static final int SEC = 60;
+    private static final int MIN = 60;
+    private static final int HOUR = 24;
+    private static final int DAY = 30;
+    private static final int MONTH = 12;
 
     public static LocalDateTime formatterLocalDateTime(String time) {
         DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm");
@@ -14,4 +20,32 @@ public static String formatterString(LocalDateTime time) {
         DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm");
         return time.format(formatter);
     }
+
+    public static String toRelativeTimeFormat(LocalDateTime localDateTime) {
+        LocalDateTime now = LocalDateTime.now();
+        long diffTime = localDateTime.until(now, ChronoUnit.SECONDS);
+
+        if (diffTime < SEC) {
+            return diffTime + "초 전";
+        }
+        diffTime = diffTime / SEC;
+        if (diffTime < MIN) {
+            return diffTime + "분 전";
+        }
+        diffTime = diffTime / MIN;
+        if (diffTime < HOUR) {
+            return diffTime + "시간 전";
+        }
+        diffTime = diffTime / HOUR;
+        if (diffTime < DAY) {
+            return diffTime + "일 전";
+        }
+        diffTime = diffTime / DAY;
+        if (diffTime < MONTH) {
+            return diffTime + "개월 전";
+        }
+
+        diffTime = diffTime / MONTH;
+        return diffTime + "년 전";
+    }
 }