refactor: 졸업학점 계산기 엑셀 업로드 리팩토링 - 1차 (#2045)

* feat: 파일 확장자 검증 어노테이션 추가

* feat: GraduationExcelService 추가

* chore: 미사용 코드 삭제

* chore: getKoinSemester 메소드 도메인 객체로 이동

* fix: GradeExcelData 스킵 메소드 네이밍 수정

* fix: Parser 메소드 삭제

* fix: GradeExcelData 합계 여부 메소드 네이밍 수정

* refactor: getKoinSemester 메소드 리펙토링

* fix: 미사용 상수 삭제

* fix: 미사용 예외 클래스 삭제

* fix: 엑셀 상수 네이밍 및 값 수정

* fix: GraduationExcelService 불필요한 어노테이션 삭제

* feat: Validated 어노테이션 추가

* feat: ConstraintViolationException 핸들러 추가

Author: Soundbar91

src/main/java/in/koreatech/koin/domain/graduation/controller/GraduationApi.java

@@ -15,6 +15,7 @@
 import in.koreatech.koin.domain.graduation.dto.GraduationCourseCalculationResponse;
 import in.koreatech.koin.domain.graduation.model.GeneralEducationArea;
 import in.koreatech.koin.global.auth.Auth;
+import in.koreatech.koin.global.validation.FileTypeValid;
 import io.swagger.v3.oas.annotations.Operation;
 import io.swagger.v3.oas.annotations.media.Content;
 import io.swagger.v3.oas.annotations.media.Schema;
@@ -53,7 +54,7 @@ ResponseEntity<Void> createStudentCourseCalculation(
     @SecurityRequirement(name = "Jwt Authentication")
     @PostMapping("/graduation/excel/upload")
     ResponseEntity<String> uploadStudentGradeExcelFile(
-        @RequestParam(value = "file") MultipartFile file,
+        @FileTypeValid(extensions = {"xls", "xlsx"}) @RequestParam(value = "file") MultipartFile file,
         @Auth(permit = {STUDENT}) Integer userId
     );
 

src/main/java/in/koreatech/koin/domain/graduation/controller/GraduationController.java

@@ -1,12 +1,13 @@
 package in.koreatech.koin.domain.graduation.controller;
 
-import java.io.IOException;
-import java.util.List;
-
 import static in.koreatech.koin.domain.user.model.UserType.COUNCIL;
 import static in.koreatech.koin.domain.user.model.UserType.STUDENT;
 
+import java.io.IOException;
+import java.util.List;
+
 import org.springframework.http.ResponseEntity;
+import org.springframework.validation.annotation.Validated;
 import org.springframework.web.bind.annotation.GetMapping;
 import org.springframework.web.bind.annotation.PostMapping;
 import org.springframework.web.bind.annotation.RequestParam;
@@ -20,8 +21,10 @@
 import in.koreatech.koin.domain.graduation.service.GraduationService;
 import in.koreatech.koin.domain.user.model.UserType;
 import in.koreatech.koin.global.auth.Auth;
+import in.koreatech.koin.global.validation.FileTypeValid;
 import lombok.RequiredArgsConstructor;
 
+@Validated
 @RestController
 @RequiredArgsConstructor
 public class GraduationController implements GraduationApi {
@@ -37,7 +40,7 @@ public ResponseEntity<Void> createStudentCourseCalculation(
 
     @PostMapping("/graduation/excel/upload")
     public ResponseEntity<String> uploadStudentGradeExcelFile(
-        @RequestParam(value = "file") MultipartFile file,
+        @FileTypeValid(extensions = {"xls", "xlsx"}) @RequestParam(value = "file") MultipartFile file,
         @Auth(permit = {UserType.STUDENT}) Integer userId
     ) {
         try {

src/main/java/in/koreatech/koin/domain/graduation/exception/ExcelFileCheckException.java

@@ -1,7 +1,8 @@
 package in.koreatech.koin.domain.graduation.model;
 
-import org.apache.poi.ss.usermodel.Cell;
-import org.apache.poi.ss.usermodel.Row;
+import static in.koreatech.koin.global.code.ApiResponseCode.INVALID_SEMESTER_REGEX;
+
+import in.koreatech.koin.global.exception.CustomException;
 
 public record GradeExcelData(
     String year,
@@ -15,29 +16,32 @@ public record GradeExcelData(
     String grade,
     String retakeStatus
 ) {
-    public static GradeExcelData fromRow(Row row) {
-        return new GradeExcelData(
-            getCellValueAsString(row.getCell(1)),
-            getCellValueAsString(row.getCell(2)),
-            getCellValueAsString(row.getCell(4)),
-            getCellValueAsString(row.getCell(5)),
-            getCellValueAsString(row.getCell(6)),
-            getCellValueAsString(row.getCell(7)),
-            getCellValueAsString(row.getCell(8)),
-            getCellValueAsString(row.getCell(9)),
-            getCellValueAsString(row.getCell(10)),
-            getCellValueAsString(row.getCell(11))
-        );
+
+    private static final String MIDDLE_TOTAL = "소 계";
+    private static final String FAIL = "F";
+    private static final String UNSATISFACTORY = "U";
+    private static final String TOTAL = "합 계";
+    private static final String FIRST_SEMESTER = "1";
+    private static final String SECOND_SEMESTER = "2";
+    private static final String SUMMER_SEMESTER = "하계";
+    private static final String WINTER_SEMESTER = "동계";
+
+    public boolean isSkipRow() {
+        return classTitle.equals(MIDDLE_TOTAL) ||
+            grade.equals(FAIL) ||
+            grade.equals(UNSATISFACTORY);
+    }
+
+    public boolean isTotalRow() {
+        return classTitle.equals(TOTAL);
     }
 
-    private static String getCellValueAsString(Cell cell) {
-        if (cell == null) {
-            return "";
-        }
-        return switch (cell.getCellType()) {
-            case STRING -> cell.getStringCellValue();
-            case NUMERIC -> String.valueOf((int)cell.getNumericCellValue());
-            default -> "";
+    public String getKoinSemester() {
+        return switch (semester) {
+            case FIRST_SEMESTER, SECOND_SEMESTER -> year + semester;
+            case WINTER_SEMESTER -> year + "-" + "겨울";
+            case SUMMER_SEMESTER -> year + "-" + "여름";
+            default -> throw CustomException.of(INVALID_SEMESTER_REGEX);
         };
     }
 }

src/main/java/in/koreatech/koin/domain/graduation/exception/ExcelFileNotFoundException.java

@@ -0,0 +1,68 @@
+package in.koreatech.koin.domain.graduation.service;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.ArrayList;
+import java.util.List;
+
+import org.apache.poi.ss.usermodel.Cell;
+import org.apache.poi.ss.usermodel.Row;
+import org.apache.poi.ss.usermodel.Sheet;
+import org.apache.poi.ss.usermodel.Workbook;
+import org.apache.poi.xssf.usermodel.XSSFWorkbook;
+import org.springframework.stereotype.Service;
+import org.springframework.web.multipart.MultipartFile;
+
+import in.koreatech.koin.domain.graduation.model.GradeExcelData;
+
+@Service
+public class GraduationExcelService {
+
+    public List<GradeExcelData> parseStudentGradeFromExcel(MultipartFile file) throws IOException {
+        List<GradeExcelData> gradeExcelDatas = new ArrayList<>();
+
+        try (InputStream inputStream = file.getInputStream();
+             Workbook workbook = new XSSFWorkbook(inputStream)
+        ) {
+            Sheet sheet = workbook.getSheetAt(0);
+
+            for (Row row : sheet) {
+                GradeExcelData gradeExcelData = fromRow(row);
+                if (row.getRowNum() == 0 || gradeExcelData.isSkipRow()) {
+                    continue;
+                }
+                if (gradeExcelData.isTotalRow()) {
+                    break;
+                }
+                gradeExcelDatas.add(gradeExcelData);
+            }
+        }
+        return gradeExcelDatas;
+    }
+
+    private GradeExcelData fromRow(Row row) {
+        return new GradeExcelData(
+            getCellValueAsString(row.getCell(1)),
+            getCellValueAsString(row.getCell(2)),
+            getCellValueAsString(row.getCell(4)),
+            getCellValueAsString(row.getCell(5)),
+            getCellValueAsString(row.getCell(6)),
+            getCellValueAsString(row.getCell(7)),
+            getCellValueAsString(row.getCell(8)),
+            getCellValueAsString(row.getCell(9)),
+            getCellValueAsString(row.getCell(10)),
+            getCellValueAsString(row.getCell(11))
+        );
+    }
+
+    private String getCellValueAsString(Cell cell) {
+        if (cell == null)
+            return "";
+
+        return switch (cell.getCellType()) {
+            case STRING -> cell.getStringCellValue();
+            case NUMERIC -> String.valueOf((int)cell.getNumericCellValue());
+            default -> "";
+        };
+    }
+}