From 511aafaf6b951640f4ed164a4dd5ad41ba3efb2e Mon Sep 17 00:00:00 2001
From: sunninz <tnals00718@gmail.com>
Date: Sat, 13 Sep 2025 10:42:34 +0900
Subject: [PATCH] =?UTF-8?q?:sparkles:=20(#307)=20lectureId=20=EA=B8=B0?=
 =?UTF-8?q?=EB=B0=98=20className=20=EC=A1=B0=ED=9A=8C?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .../lecture/controller/LectureController.java     |  8 +++++++-
 .../dto/response/ClassNameResponseDTO.java        | 15 +++++++++++++++
 .../domain/lecture/service/LectureService.java    |  3 +++
 .../lecture/service/LectureServiceImpl.java       | 13 +++++++++++++
 4 files changed, 38 insertions(+), 1 deletion(-)
 create mode 100644 backend/src/main/java/org/example/backend/domain/lecture/dto/response/ClassNameResponseDTO.java

diff --git a/backend/src/main/java/org/example/backend/domain/lecture/controller/LectureController.java b/backend/src/main/java/org/example/backend/domain/lecture/controller/LectureController.java
index 76a1e231..cf53df4c 100644
--- a/backend/src/main/java/org/example/backend/domain/lecture/controller/LectureController.java
+++ b/backend/src/main/java/org/example/backend/domain/lecture/controller/LectureController.java
@@ -101,4 +101,10 @@ public ApiResponse<StudentTodayLectureResponseDTO> getStudentLectures(@RequestPa
         return ApiResponse.onSuccess(result);
     }
 
-}
+    // lecture id로 class id 조회
+    @GetMapping("/classes/{lectureId}")
+    public ApiResponse<ClassNameResponseDTO> getClassId(@PathVariable("lectureId") UUID lectureId) {
+        ClassNameResponseDTO result = lectureService.getClassId(lectureId);
+        return ApiResponse.onSuccess(result);
+    }
+}
\ No newline at end of file
diff --git a/backend/src/main/java/org/example/backend/domain/lecture/dto/response/ClassNameResponseDTO.java b/backend/src/main/java/org/example/backend/domain/lecture/dto/response/ClassNameResponseDTO.java
new file mode 100644
index 00000000..363bd7b3
--- /dev/null
+++ b/backend/src/main/java/org/example/backend/domain/lecture/dto/response/ClassNameResponseDTO.java
@@ -0,0 +1,15 @@
+package org.example.backend.domain.lecture.dto.response;
+
+import lombok.AllArgsConstructor;
+import lombok.Builder;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+
+
+@Getter
+@Builder
+@NoArgsConstructor
+@AllArgsConstructor
+public class ClassNameResponseDTO {
+    private String className;
+}
diff --git a/backend/src/main/java/org/example/backend/domain/lecture/service/LectureService.java b/backend/src/main/java/org/example/backend/domain/lecture/service/LectureService.java
index a513b30d..b5203a51 100644
--- a/backend/src/main/java/org/example/backend/domain/lecture/service/LectureService.java
+++ b/backend/src/main/java/org/example/backend/domain/lecture/service/LectureService.java
@@ -1,6 +1,7 @@
 package org.example.backend.domain.lecture.service;
 
 import org.example.backend.domain.lecture.dto.request.LectureRequestDTO;
+import org.example.backend.domain.lecture.dto.response.ClassNameResponseDTO;
 import org.example.backend.domain.lecture.dto.response.LectureRecordingResponseDTO;
 import org.example.backend.domain.lecture.dto.response.LectureResponseDTO;
 import org.example.backend.domain.lecture.dto.response.TodayLectureResponseDTO;
@@ -27,4 +28,6 @@ public interface LectureService {
     List<UUID> mapNotes(UUID lectureId, List<UUID> lectureNoteIds);
 
     List<TodayLectureResponseDTO> getClassListByProfessor(LocalDate date);
+
+    ClassNameResponseDTO getClassId(UUID lectureId);
 }
diff --git a/backend/src/main/java/org/example/backend/domain/lecture/service/LectureServiceImpl.java b/backend/src/main/java/org/example/backend/domain/lecture/service/LectureServiceImpl.java
index 84333b6b..341b33ed 100644
--- a/backend/src/main/java/org/example/backend/domain/lecture/service/LectureServiceImpl.java
+++ b/backend/src/main/java/org/example/backend/domain/lecture/service/LectureServiceImpl.java
@@ -6,6 +6,7 @@
 import org.example.backend.domain.classroom.repository.ClassroomRepository;
 import org.example.backend.domain.lecture.converter.LectureConverter;
 import org.example.backend.domain.lecture.dto.request.LectureRequestDTO;
+import org.example.backend.domain.lecture.dto.response.ClassNameResponseDTO;
 import org.example.backend.domain.lecture.dto.response.LectureRecordingResponseDTO;
 import org.example.backend.domain.lecture.dto.response.LectureResponseDTO;
 import org.example.backend.domain.lecture.dto.response.TodayLectureResponseDTO;
@@ -303,5 +304,17 @@ public void updateLectureSessions(UUID classId) {
         lectureRepository.saveAll(lectures);
     }
 
+    // 강의 id 기반 클래스 id 조회
+    @Override
+    public ClassNameResponseDTO getClassId(UUID lectureId) {
+        // 1. 강의 조회
+        Lecture lecture = lectureRepository.findById(lectureId)
+                .orElseThrow(() -> new LectureException(LectureErrorCode.LECTURE_NOT_FOUND));
+        // 2. 클래스 조회
+        Classroom classroom = lecture.getClassroom();
 
+        return ClassNameResponseDTO.builder()
+                .className(classroom.getClassName())
+                .build();
+    }
 }