feat: S3 upload detected 엔드포인트 추가 및 Lambda invoke 멱등성 보강

src/main/java/me/thinkcat/opic/practice/controller/AnswerController.java

@@ -4,6 +4,7 @@
 import lombok.RequiredArgsConstructor;
 import me.thinkcat.opic.practice.dto.request.CompleteAnswerUploadRequest;
 import me.thinkcat.opic.practice.dto.request.PrepareAnswerUploadRequest;
+import me.thinkcat.opic.practice.dto.request.S3UploadDetectedRequest;
 import me.thinkcat.opic.practice.dto.request.UpdateFeedbackRequest;
 import me.thinkcat.opic.practice.dto.request.UpdateFeedbackStatusRequest;
 import me.thinkcat.opic.practice.dto.request.UpdateTranscriptionRequest;
@@ -74,6 +75,20 @@ public ResponseEntity<CommonResponse<AnswerResponse>> completeAnswerUpload(
         return ResponseEntity.ok(response);
     }
 
+    @PostMapping("/internal/s3-upload-detected")
+    public ResponseEntity<CommonResponse<Void>> handleS3UploadDetected(
+            @Valid @RequestBody S3UploadDetectedRequest request) {
+
+        answerService.handleS3UploadDetected(request.getFileKey());
+
+        CommonResponse<Void> response = CommonResponse.<Void>builder()
+                .success(true)
+                .message("S3 upload detected processed successfully")
+                .build();
+
+        return ResponseEntity.ok(response);
+    }
+
     @PatchMapping("/internal/transcription")
     public ResponseEntity<CommonResponse<Void>> updateTranscription(
             @Valid @RequestBody UpdateTranscriptionRequest request) {

src/main/java/me/thinkcat/opic/practice/controller/DrillAnswerController.java

@@ -6,6 +6,7 @@
 import me.thinkcat.opic.practice.config.security.annotation.AuthUser;
 import me.thinkcat.opic.practice.dto.CommonResponse;
 import me.thinkcat.opic.practice.dto.request.PrepareDrillAnswerUploadRequest;
+import me.thinkcat.opic.practice.dto.request.S3UploadDetectedRequest;
 import me.thinkcat.opic.practice.dto.request.SubmitDrillAnswerRequest;
 import me.thinkcat.opic.practice.dto.request.UpdateDrillFeedbackRequest;
 import me.thinkcat.opic.practice.dto.request.UpdateDrillTranscriptionRequest;
@@ -129,6 +130,20 @@ public ResponseEntity<CommonResponse<QuestionPracticeHistoryResponse>> getQuesti
         return ResponseEntity.ok(response);
     }
 
+    @PostMapping("/internal/s3-upload-detected")
+    public ResponseEntity<CommonResponse<Void>> handleS3UploadDetected(
+            @Valid @RequestBody S3UploadDetectedRequest request) {
+
+        drillAnswerService.handleS3UploadDetected(request.getFileKey());
+
+        CommonResponse<Void> response = CommonResponse.<Void>builder()
+                .success(true)
+                .message("Drill S3 upload detected processed successfully")
+                .build();
+
+        return ResponseEntity.ok(response);
+    }
+
     @PatchMapping("/internal/feedback-status")
     public ResponseEntity<CommonResponse<Void>> updateDrillFeedbackStatus(
             @Valid @RequestBody UpdateFeedbackStatusRequest request) {

src/main/java/me/thinkcat/opic/practice/dto/request/S3UploadDetectedRequest.java

@@ -0,0 +1,19 @@
+package me.thinkcat.opic.practice.dto.request;
+
+import jakarta.validation.constraints.NotBlank;
+import jakarta.validation.constraints.Pattern;
+import lombok.AllArgsConstructor;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import lombok.Setter;
+
+@Getter
+@Setter
+@NoArgsConstructor
+@AllArgsConstructor
+public class S3UploadDetectedRequest {
+
+    @NotBlank(message = "File key is required")
+    @Pattern(regexp = "^uploads/.+", message = "File key must start with 'uploads/'")
+    private String fileKey;
+}

src/main/java/me/thinkcat/opic/practice/repository/AnswerRepository.java

@@ -1,7 +1,9 @@
 package me.thinkcat.opic.practice.repository;
 
+import jakarta.persistence.LockModeType;
 import me.thinkcat.opic.practice.entity.Answer;
 import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.data.jpa.repository.Lock;
 import org.springframework.data.jpa.repository.Query;
 import org.springframework.data.repository.query.Param;
 import org.springframework.stereotype.Repository;
@@ -20,6 +22,14 @@ public interface AnswerRepository extends JpaRepository<Answer, Long> {
 
     Optional<Answer> findByAudioUrl(String audioUrl);
 
+    @Lock(LockModeType.PESSIMISTIC_WRITE)
+    @Query("SELECT a FROM Answer a WHERE a.id = :id")
+    Optional<Answer> findByIdForUpdate(@Param("id") Long id);
+
+    @Lock(LockModeType.PESSIMISTIC_WRITE)
+    @Query("SELECT a FROM Answer a WHERE a.audioUrl = :audioUrl")
+    Optional<Answer> findByAudioUrlForUpdate(@Param("audioUrl") String audioUrl);
+
     List<Answer> findByUploadStatusCodeAndUpdatedAtBefore(String uploadStatusCode, LocalDateTime threshold);
 
     List<Answer> findByFeedbackStatusCodeAndUpdatedAtBefore(String feedbackStatusCode, LocalDateTime threshold);

src/main/java/me/thinkcat/opic/practice/repository/DrillAnswerRepository.java

@@ -1,7 +1,9 @@
 package me.thinkcat.opic.practice.repository;
 
+import jakarta.persistence.LockModeType;
 import me.thinkcat.opic.practice.entity.DrillAnswer;
 import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.data.jpa.repository.Lock;
 import org.springframework.data.jpa.repository.Query;
 import org.springframework.data.repository.query.Param;
 import org.springframework.stereotype.Repository;
@@ -15,6 +17,14 @@ public interface DrillAnswerRepository extends JpaRepository<DrillAnswer, Long>
 
     Optional<DrillAnswer> findByAudioUrl(String audioUrl);
 
+    @Lock(LockModeType.PESSIMISTIC_WRITE)
+    @Query("SELECT d FROM DrillAnswer d WHERE d.id = :id")
+    Optional<DrillAnswer> findByIdForUpdate(@Param("id") Long id);
+
+    @Lock(LockModeType.PESSIMISTIC_WRITE)
+    @Query("SELECT d FROM DrillAnswer d WHERE d.audioUrl = :audioUrl")
+    Optional<DrillAnswer> findByAudioUrlForUpdate(@Param("audioUrl") String audioUrl);
+
     List<DrillAnswer> findByUserIdAndQuestionIdAndUploadStatusCodeOrderByCreatedAtDesc(
             Long userId, Long questionId, String uploadStatusCode);
 

src/main/java/me/thinkcat/opic/practice/service/AnswerService.java

@@ -17,9 +17,11 @@
 import me.thinkcat.opic.practice.exception.ResourceNotFoundException;
 import me.thinkcat.opic.practice.exception.ValidationException;
 import me.thinkcat.opic.practice.entity.Question;
+import me.thinkcat.opic.practice.entity.User;
 import me.thinkcat.opic.practice.repository.AnswerRepository;
 import me.thinkcat.opic.practice.repository.QuestionRepository;
 import me.thinkcat.opic.practice.repository.SessionRepository;
+import me.thinkcat.opic.practice.repository.UserRepository;
 import org.springframework.stereotype.Service;
 import org.springframework.transaction.annotation.Transactional;
 
@@ -39,6 +41,7 @@ public class AnswerService {
     private final AnswerRepository answerRepository;
     private final SessionRepository sessionRepository;
     private final QuestionRepository questionRepository;
+    private final UserRepository userRepository;
     private final PresignedUrlService presignedUrlService;
     private final FeedbackLambdaService feedbackLambdaService;
 
@@ -88,24 +91,26 @@ public AnswerResponse completeAnswerUpload(
             Long answerId,
             Integer durationMs) {
 
-        Answer answer = answerRepository.findById(answerId)
+        Answer answer = answerRepository.findByIdForUpdate(answerId)
                 .orElseThrow(() -> new ResourceNotFoundException("Answer not found with id: " + answerId));
 
         sessionRepository.findByIdAndUserId(answer.getSessionId(), userId)
                 .orElseThrow(() -> new ValidationException("Unauthorized access to answer"));
 
-        if (answer.isUploadSuccess()) {
-            log.warn("event=answer_upload_already_done | who={} | answerId={}", userId, answerId);
-            return resolveAnswerResponse(answer);
+        if (answer.isUploadPending()) {
+            answer.markUploadSuccess();
+            log.info("event=answer_upload_complete | who={} | answerId={} | audioUrl={}",
+                    userId, answerId, answer.getAudioUrl());
         }
 
-        answer.markUploadSuccess();
-        if (durationMs != null) {
+        if (durationMs != null && answer.getDurationMs() == 0) {
             answer.setDurationMs(durationMs);
         }
 
-        log.info("event=answer_upload_complete | who={} | answerId={} | audioUrl={}",
-                userId, answerId, answer.getAudioUrl());
+        if (!answer.isFeedbackNone()) {
+            log.warn("event=answer_feedback_already_requested | who={} | answerId={}", userId, answerId);
+            return resolveAnswerResponse(answerRepository.save(answer));
+        }
 
         if (userRole == UserRole.PAID || userRole == UserRole.ADMIN || featureFlagService.isEnabled("ai-for-free")) {
             answer.requestFeedback();
@@ -123,6 +128,51 @@ public AnswerResponse completeAnswerUpload(
         return resolveAnswerResponse(updatedAnswer);
     }
 
+    @Transactional
+    public void handleS3UploadDetected(String fileKey) {
+        Answer answer = answerRepository.findByAudioUrlForUpdate(fileKey).orElse(null);
+        if (answer == null) {
+            log.warn("event=s3_upload_detected_not_found | fileKey={}", fileKey);
+            return;
+        }
+
+        if (answer.isUploadPending()) {
+            answer.markUploadSuccess();
+            log.info("event=s3_upload_detected_marked_success | answerId={} | audioUrl={}",
+                    answer.getId(), fileKey);
+        }
+
+        if (!answer.isFeedbackNone()) {
+            log.warn("event=s3_upload_detected_feedback_already_requested | answerId={} | audioUrl={}",
+                    answer.getId(), fileKey);
+            answerRepository.save(answer);
+            return;
+        }
+
+        Long userId = sessionRepository.findById(answer.getSessionId())
+                .orElseThrow(() -> new ResourceNotFoundException("Session not found for answer: " + answer.getId()))
+                .getUserId();
+
+        UserRole userRole = userRepository.findById(userId)
+                .map(User::getUserRole)
+                .orElse(UserRole.FREE);
+
+        if (userRole == UserRole.PAID || userRole == UserRole.ADMIN || featureFlagService.isEnabled("ai-for-free")) {
+            answer.requestFeedback();
+            answerRepository.save(answer);
+            log.info("event=s3_upload_detected_feedback_requested | who={} | answerId={} | audioUrl={}",
+                    userId, answer.getId(), fileKey);
+            String questionText = questionRepository.findById(answer.getQuestionId())
+                    .map(Question::getQuestion)
+                    .orElse(null);
+            feedbackLambdaService.invokeSessionFeedbackAsync(fileKey, userId, questionText);
+            return;
+        }
+
+        answerRepository.save(answer);
+        log.info("event=s3_upload_detected_no_feedback | who={} | answerId={}", userId, answer.getId());
+    }
+
     @Transactional(readOnly = true)
     public List<AnswerResponse> getSessionAnswers(Long sessionId, Long userId) {
         sessionRepository.findByIdAndUserId(sessionId, userId)

src/main/java/me/thinkcat/opic/practice/service/DrillAnswerService.java

@@ -17,10 +17,12 @@
 import me.thinkcat.opic.practice.entity.UserRole;
 import me.thinkcat.opic.practice.exception.ResourceNotFoundException;
 import me.thinkcat.opic.practice.exception.ValidationException;
+import me.thinkcat.opic.practice.entity.User;
 import me.thinkcat.opic.practice.repository.CategoryRepository;
 import me.thinkcat.opic.practice.repository.DrillAnswerRepository;
 import me.thinkcat.opic.practice.repository.QuestionRepository;
 import me.thinkcat.opic.practice.repository.RecentDrillQuestionProjection;
+import me.thinkcat.opic.practice.repository.UserRepository;
 import org.springframework.stereotype.Service;
 import org.springframework.transaction.annotation.Transactional;
 
@@ -40,6 +42,7 @@ public class DrillAnswerService {
     private final DrillAnswerRepository drillAnswerRepository;
     private final QuestionRepository questionRepository;
     private final CategoryRepository categoryRepository;
+    private final UserRepository userRepository;
     private final PresignedUrlService presignedUrlService;
     private final FeedbackLambdaService feedbackLambdaService;
 
@@ -83,25 +86,27 @@ public PrepareDrillAnswerUploadResponse prepareDrillAnswerUpload(
 
     @Transactional
     public DrillAnswerResponse submitDrillAnswer(Long userId, UserRole userRole, Long drillAnswerId, Integer durationMs) {
-        DrillAnswer answer = drillAnswerRepository.findById(drillAnswerId)
+        DrillAnswer answer = drillAnswerRepository.findByIdForUpdate(drillAnswerId)
                 .orElseThrow(() -> new ResourceNotFoundException("Drill answer not found with id: " + drillAnswerId));
 
         if (!answer.getUserId().equals(userId)) {
             throw new ValidationException("Unauthorized access to drill answer");
         }
 
-        if (answer.isUploadSuccess()) {
-            log.warn("event=drill_submit_already_done | who={} | drillAnswerId={}", userId, drillAnswerId);
-            return resolveDrillAnswerResponse(answer);
+        if (answer.isUploadPending()) {
+            answer.markUploadSuccess();
+            log.info("event=drill_submit | who={} | drillAnswerId={} | audioUrl={}",
+                    userId, drillAnswerId, answer.getAudioUrl());
         }
 
-        answer.markUploadSuccess();
-        if (durationMs != null) {
+        if (durationMs != null && answer.getDurationMs() == 0) {
             answer.setDurationMs(durationMs);
         }
 
-        log.info("event=drill_submit | who={} | drillAnswerId={} | audioUrl={}",
-                userId, drillAnswerId, answer.getAudioUrl());
+        if (!answer.isFeedbackNone()) {
+            log.warn("event=drill_feedback_already_requested | who={} | drillAnswerId={}", userId, drillAnswerId);
+            return resolveDrillAnswerResponse(drillAnswerRepository.save(answer));
+        }
 
         if (userRole == UserRole.PAID || userRole == UserRole.ADMIN || featureFlagService.isEnabled("ai-for-free")) {
             answer.requestFeedback();
@@ -119,6 +124,48 @@ public DrillAnswerResponse submitDrillAnswer(Long userId, UserRole userRole, Lon
         return resolveDrillAnswerResponse(updatedAnswer);
     }
 
+    @Transactional
+    public void handleS3UploadDetected(String fileKey) {
+        DrillAnswer answer = drillAnswerRepository.findByAudioUrlForUpdate(fileKey).orElse(null);
+        if (answer == null) {
+            log.warn("event=drill_s3_upload_detected_not_found | fileKey={}", fileKey);
+            return;
+        }
+
+        if (answer.isUploadPending()) {
+            answer.markUploadSuccess();
+            log.info("event=drill_s3_upload_detected_marked_success | drillAnswerId={} | audioUrl={}",
+                    answer.getId(), fileKey);
+        }
+
+        if (!answer.isFeedbackNone()) {
+            log.warn("event=drill_s3_upload_detected_feedback_already_requested | drillAnswerId={} | audioUrl={}",
+                    answer.getId(), fileKey);
+            drillAnswerRepository.save(answer);
+            return;
+        }
+
+        UserRole userRole = userRepository.findById(answer.getUserId())
+                .map(User::getUserRole)
+                .orElse(UserRole.FREE);
+
+        if (userRole == UserRole.PAID || userRole == UserRole.ADMIN || featureFlagService.isEnabled("ai-for-free")) {
+            answer.requestFeedback();
+            drillAnswerRepository.save(answer);
+            log.info("event=drill_s3_upload_detected_feedback_requested | who={} | drillAnswerId={} | audioUrl={}",
+                    answer.getUserId(), answer.getId(), fileKey);
+            String questionText = questionRepository.findById(answer.getQuestionId())
+                    .map(Question::getQuestion)
+                    .orElse(null);
+            feedbackLambdaService.invokeDrillAnswerFeedbackAsync(fileKey, answer.getUserId(), questionText);
+            return;
+        }
+
+        drillAnswerRepository.save(answer);
+        log.info("event=drill_s3_upload_detected_no_feedback | who={} | drillAnswerId={}",
+                answer.getUserId(), answer.getId());
+    }
+
     @Transactional(readOnly = true)
     public List<RecentDrillQuestionResponse> getRecentlyPracticedQuestions(Long userId) {
         List<RecentDrillQuestionProjection> projections = drillAnswerRepository