Feat: 알림 시스템 기본 인프라 구축 (#141)

src/main/java/com/back/domain/notification/controller/NotificationController.java

@@ -0,0 +1,157 @@
+package com.back.domain.notification.controller;
+
+import com.back.domain.notification.dto.NotificationCreateRequest;
+import com.back.domain.notification.dto.NotificationResponse;
+import com.back.domain.notification.dto.NotificationListResponse;
+import com.back.domain.notification.entity.Notification;
+import com.back.domain.notification.service.NotificationService;
+import com.back.domain.studyroom.entity.Room;
+import com.back.domain.studyroom.repository.RoomRepository;
+import com.back.domain.user.entity.User;
+import com.back.domain.user.repository.UserRepository;
+import com.back.global.common.dto.RsData;
+import com.back.global.exception.CustomException;
+import com.back.global.exception.ErrorCode;
+import com.back.global.security.user.CustomUserDetails;
+import io.swagger.v3.oas.annotations.Operation;
+import io.swagger.v3.oas.annotations.Parameter;
+import io.swagger.v3.oas.annotations.tags.Tag;
+import lombok.RequiredArgsConstructor;
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.data.domain.Page;
+import org.springframework.data.domain.PageRequest;
+import org.springframework.data.domain.Pageable;
+import org.springframework.http.ResponseEntity;
+import org.springframework.security.core.annotation.AuthenticationPrincipal;
+import org.springframework.web.bind.annotation.*;
+
+@Slf4j
+@RestController
+@RequiredArgsConstructor
+@RequestMapping("/api/notifications")
+@Tag(name = "알림", description = "알림 관련 API")
+public class NotificationController {
+
+    private final NotificationService notificationService;
+    private final UserRepository userRepository;
+    private final RoomRepository roomRepository;
+
+    @Operation(summary = "알림 전송", description = "USER/ROOM/COMMUNITY/SYSTEM 타입별 알림 생성 및 전송")
+    @PostMapping
+    public ResponseEntity<RsData<NotificationResponse>> createNotification(
+            @Parameter(hidden = true) @AuthenticationPrincipal CustomUserDetails userDetails,
+            @RequestBody NotificationCreateRequest request) {
+
+        log.info("알림 전송 요청 - 타입: {}, 제목: {}", request.targetType(), request.title());
+
+        Notification notification = switch (request.targetType()) {
+            case "USER" -> {
+                User targetUser = userRepository.findById(request.targetId())
+                        .orElseThrow(() -> new CustomException(ErrorCode.USER_NOT_FOUND));
+                yield notificationService.createPersonalNotification(
+                        targetUser,
+                        request.title(),
+                        request.message(),
+                        request.redirectUrl()
+                );
+            }
+            case "ROOM" -> {
+                Room room = roomRepository.findById(request.targetId())
+                        .orElseThrow(() -> new CustomException(ErrorCode.ROOM_NOT_FOUND));
+                yield notificationService.createRoomNotification(
+                        room,
+                        request.title(),
+                        request.message(),
+                        request.redirectUrl()
+                );
+            }
+            case "COMMUNITY" -> {
+                User targetUser = userRepository.findById(request.targetId())
+                        .orElseThrow(() -> new CustomException(ErrorCode.USER_NOT_FOUND));
+                yield notificationService.createCommunityNotification(
+                        targetUser,
+                        request.title(),
+                        request.message(),
+                        request.redirectUrl()
+                );
+            }
+            case "SYSTEM" -> {
+                yield notificationService.createSystemNotification(
+                        request.title(),
+                        request.message(),
+                        request.redirectUrl()
+                );
+            }
+            default -> throw new IllegalArgumentException("유효하지 않은 알림 타입입니다: " + request.targetType());
+        };
+
+        NotificationResponse response = NotificationResponse.from(notification);
+
+        return ResponseEntity.ok(RsData.success("알림 전송 성공", response));
+    }
+
+    @Operation(summary = "알림 목록 조회", description = "사용자의 알림 목록 조회 (페이징)")
+    @GetMapping
+    public ResponseEntity<RsData<NotificationListResponse>> getNotifications(
+            @Parameter(hidden = true) @AuthenticationPrincipal CustomUserDetails userDetails,
+            @Parameter(description = "페이지 번호 (0부터 시작)") @RequestParam(defaultValue = "0") int page,
+            @Parameter(description = "페이지 크기") @RequestParam(defaultValue = "20") int size,
+            @Parameter(description = "읽지 않은 알림만 조회") @RequestParam(defaultValue = "false") boolean unreadOnly) {
+
+        log.info("알림 목록 조회 - 유저 ID: {}, 읽지 않은 것만: {}", userDetails.getUserId(), unreadOnly);
+
+        Pageable pageable = PageRequest.of(page, size);
+        Page<Notification> notifications;
+
+        if (unreadOnly) {
+            notifications = notificationService.getUnreadNotifications(userDetails.getUserId(), pageable);
+        } else {
+            notifications = notificationService.getUserNotifications(userDetails.getUserId(), pageable);
+        }
+
+        long unreadCount = notificationService.getUnreadCount(userDetails.getUserId());
+
+        NotificationListResponse response = NotificationListResponse.from(
+                notifications,
+                userDetails.getUserId(),
+                unreadCount,
+                notificationService
+        );
+
+        return ResponseEntity.ok(RsData.success("알림 목록 조회 성공", response));
+    }
+
+    @Operation(summary = "알림 읽음 처리", description = "특정 알림을 읽음 상태로 변경")
+    @PutMapping("/{notificationId}/read")
+    public ResponseEntity<RsData<NotificationResponse>> markAsRead(
+            @Parameter(hidden = true) @AuthenticationPrincipal CustomUserDetails userDetails,
+            @Parameter(description = "알림 ID") @PathVariable Long notificationId) {
+
+        log.info("알림 읽음 처리 - 알림 ID: {}, 유저 ID: {}", notificationId, userDetails.getUserId());
+
+        User user = userRepository.findById(userDetails.getUserId())
+                .orElseThrow(() -> new CustomException(ErrorCode.USER_NOT_FOUND));
+
+        notificationService.markAsRead(notificationId, user);
+
+        Notification notification = notificationService.getNotification(notificationId);
+        NotificationResponse response = NotificationResponse.from(notification);
+
+        return ResponseEntity.ok(RsData.success("알림 읽음 처리 성공", response));
+    }
+
+    @Operation(summary = "모든 알림 읽음 처리", description = "사용자의 읽지 않은 모든 알림을 읽음 상태로 변경")
+    @PutMapping("/read-all")
+    public ResponseEntity<RsData<Void>> markAllAsRead(
+            @Parameter(hidden = true) @AuthenticationPrincipal CustomUserDetails userDetails) {
+
+        log.info("전체 알림 읽음 처리 - 유저 ID: {}", userDetails.getUserId());
+
+        User user = userRepository.findById(userDetails.getUserId())
+                .orElseThrow(() -> new CustomException(ErrorCode.USER_NOT_FOUND));
+
+        notificationService.markMultipleAsRead(userDetails.getUserId(), user);
+
+        return ResponseEntity.ok(RsData.success("전체 알림 읽음 처리 성공"));
+    }
+}

src/main/java/com/back/domain/notification/dto/NotificationCreateRequest.java

@@ -0,0 +1,13 @@
+package com.back.domain.notification.dto;
+
+public record NotificationCreateRequest(
+        String targetType,      // USER, ROOM, SYSTEM
+        Long targetId,          // nullable (SYSTEM일 때 null)
+        String title,
+        String message,
+        String notificationType, // STUDY_REMINDER, ROOM_JOIN 등
+        String redirectUrl,      // targetUrl
+        String scheduleType,     // ONE_TIME (향후 확장용)
+        String scheduledAt       // 예약 시간 (향후 확장용)
+) {
+}

src/main/java/com/back/domain/notification/dto/NotificationItemDto.java

@@ -0,0 +1,31 @@
+package com.back.domain.notification.dto;
+
+import com.back.domain.notification.entity.Notification;
+import com.back.domain.notification.entity.NotificationType;
+
+import java.time.LocalDateTime;
+
+/**
+ * 알림 목록 아이템 DTO
+ */
+public record NotificationItemDto(
+        Long notificationId,
+        String title,
+        String message,
+        NotificationType notificationType,
+        String targetUrl,
+        boolean isRead,
+        LocalDateTime createdAt
+) {
+    public static NotificationItemDto from(Notification notification, boolean isRead) {
+        return new NotificationItemDto(
+                notification.getId(),
+                notification.getTitle(),
+                notification.getContent(),
+                notification.getType(),
+                notification.getTargetUrl(),
+                isRead,
+                notification.getCreatedAt()
+        );
+    }
+}

src/main/java/com/back/domain/notification/dto/NotificationListResponse.java

@@ -0,0 +1,48 @@
+package com.back.domain.notification.dto;
+
+import com.back.domain.notification.entity.Notification;
+import com.back.domain.notification.service.NotificationService;
+import org.springframework.data.domain.Page;
+
+import java.util.List;
+
+/**
+ * 알림 목록 응답 DTO
+ */
+public record NotificationListResponse(
+        List<NotificationItemDto> content,
+        PageableDto pageable,
+        long unreadCount
+) {
+
+    // 페이지 정보 DTO
+    public record PageableDto(
+            int page,
+            int size,
+            boolean hasNext
+    ) {}
+
+    public static NotificationListResponse from(
+            Page<Notification> notifications,
+            Long userId,
+            long unreadCount,
+            NotificationService notificationService) {
+
+        List<NotificationItemDto> items = notifications.getContent().stream()
+                .map(notification -> {
+                    boolean isRead = notificationService.isNotificationRead(notification.getId(), userId);
+                    return NotificationItemDto.from(notification, isRead);
+                })
+                .toList();
+
+        return new NotificationListResponse(
+                items,
+                new PageableDto(
+                        notifications.getNumber(),
+                        notifications.getSize(),
+                        notifications.hasNext()
+                ),
+                unreadCount
+        );
+    }
+}

src/main/java/com/back/domain/notification/dto/NotificationResponse.java

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+package com.back.domain.notification.dto;
+
+import com.back.domain.notification.entity.Notification;
+import com.back.domain.notification.entity.NotificationType;
+
+import java.time.LocalDateTime;
+
+/**
+ * 알림 응답 DTO
+ */
+public record NotificationResponse(
+        Long notificationId,
+        String title,
+        String message,
+        NotificationType notificationType,
+        String targetUrl,
+        boolean isRead,
+        LocalDateTime createdAt,
+        LocalDateTime readAt
+) {
+    public static NotificationResponse from(Notification notification) {
+        return new NotificationResponse(
+                notification.getId(),
+                notification.getTitle(),
+                notification.getContent(),
+                notification.getType(),
+                notification.getTargetUrl(),
+                false, // 읽음 여부는 NotificationListResponse에서 처리
+                notification.getCreatedAt(),
+                null   // readAt은 NotificationRead에서 가져와야 함
+        );
+    }
+
+    public static NotificationResponse from(Notification notification, boolean isRead, LocalDateTime readAt) {
+        return new NotificationResponse(
+                notification.getId(),
+                notification.getTitle(),
+                notification.getContent(),
+                notification.getType(),
+                notification.getTargetUrl(),
+                isRead,
+                notification.getCreatedAt(),
+                readAt
+        );
+    }
+}

src/main/java/com/back/domain/notification/dto/NotificationWebSocketDto.java

@@ -0,0 +1,33 @@
+package com.back.domain.notification.dto;
+
+import com.back.domain.notification.entity.NotificationType;
+
+import java.time.LocalDateTime;
+
+public record NotificationWebSocketDto(
+        Long notificationId,
+        String title,
+        String message,
+        NotificationType notificationType,
+        String targetUrl,
+        LocalDateTime createdAt
+) {
+
+    public static NotificationWebSocketDto from(
+            Long notificationId,
+            String title,
+            String content,
+            NotificationType type,
+            String targetUrl,
+            LocalDateTime createdAt) {
+
+        return new NotificationWebSocketDto(
+                notificationId,
+                title,
+                content,
+                type,
+                targetUrl,
+                createdAt
+        );
+    }
+}