feat: Epic #499 - Real-time Notification System

ServerlessFunction/build.gradle

@@ -35,6 +35,7 @@ dependencies {
     implementation 'software.amazon.awssdk:url-connection-client'
     implementation 'software.amazon.awssdk:ssm'
     implementation 'software.amazon.awssdk:scheduler'
+    implementation 'software.amazon.awssdk:sqs'
 
     // AWS X-Ray SDK (다운스트림 서비스 추적용)
     implementation 'com.amazonaws:aws-xray-recorder-sdk-core:2.15.0'

ServerlessFunction/src/main/java/com/mzc/secondproject/serverless/common/config/AwsClients.java

@@ -11,6 +11,7 @@
 import software.amazon.awssdk.services.s3.S3Client;
 import software.amazon.awssdk.services.s3.presigner.S3Presigner;
 import software.amazon.awssdk.services.sns.SnsClient;
+import software.amazon.awssdk.services.sqs.SqsClient;
 import software.amazon.awssdk.services.ssm.SsmClient;
 
 /**
@@ -60,7 +61,12 @@ public final class AwsClients {
 	private static final SsmClient SSM_CLIENT = SsmClient.builder()
 			.overrideConfiguration(XRAY_CONFIG)
 			.build();
-
+
+	// SQS
+	private static final SqsClient SQS_CLIENT = SqsClient.builder()
+			.overrideConfiguration(XRAY_CONFIG)
+			.build();
+
 	private AwsClients() {
 		// 인스턴스화 방지
 	}
@@ -104,4 +110,8 @@ public static ComprehendClient comprehend() {
 	public static SsmClient ssm() {
 		return SSM_CLIENT;
 	}
+
+	public static SqsClient sqs() {
+		return SQS_CLIENT;
+	}
 }

ServerlessFunction/src/main/java/com/mzc/secondproject/serverless/common/config/EnvConfig.java

@@ -15,7 +15,18 @@ public final class EnvConfig {
 	private EnvConfig() {
 		// 유틸리티 클래스 - 인스턴스화 방지
 	}
-
+
+	/**
+	 * 선택적 환경 변수를 가져옵니다.
+	 * 환경 변수가 설정되지 않은 경우 null을 반환합니다.
+	 *
+	 * @param name 환경 변수 이름
+	 * @return 환경 변수 값 또는 null
+	 */
+	public static String get(String name) {
+		return System.getenv(name);
+	}
+
 	/**
 	 * 필수 환경 변수를 가져옵니다.
 	 * 환경 변수가 설정되지 않았거나 빈 문자열인 경우 IllegalStateException을 발생시킵니다.

ServerlessFunction/src/main/java/com/mzc/secondproject/serverless/common/util/JsonUtil.java

@@ -1,5 +1,7 @@
 package com.mzc.secondproject.serverless.common.util;
 
+import com.google.gson.Gson;
+import com.google.gson.GsonBuilder;
 import com.google.gson.JsonArray;
 import com.google.gson.JsonElement;
 
@@ -10,9 +12,25 @@
  * JSON 파싱 관련 공통 유틸리티
  */
 public class JsonUtil {
-
+
+	private static final Gson GSON = new GsonBuilder().create();
+
 	private JsonUtil() {
 	}
+
+	/**
+	 * 객체를 JSON 문자열로 변환
+	 */
+	public static String toJson(Object obj) {
+		return GSON.toJson(obj);
+	}
+
+	/**
+	 * JSON 문자열을 객체로 변환
+	 */
+	public static <T> T fromJson(String json, Class<T> clazz) {
+		return GSON.fromJson(json, clazz);
+	}
 
 	// 응답에서 JSON 부분만 추출
 	public static String extractJson(String response) {

ServerlessFunction/src/main/java/com/mzc/secondproject/serverless/domain/badge/service/BadgeService.java

@@ -7,6 +7,7 @@
 import com.mzc.secondproject.serverless.domain.badge.repository.BadgeRepository;
 import com.mzc.secondproject.serverless.domain.badge.strategy.BadgeConditionStrategy;
 import com.mzc.secondproject.serverless.domain.badge.strategy.BadgeConditionStrategyFactory;
+import com.mzc.secondproject.serverless.domain.notification.service.NotificationPublisher;
 import com.mzc.secondproject.serverless.domain.stats.model.UserStats;
 import com.mzc.secondproject.serverless.domain.stats.repository.UserStatsRepository;
 import org.slf4j.Logger;
@@ -24,20 +25,23 @@ public class BadgeService {
 
 	private final BadgeRepository badgeRepository;
 	private final UserStatsRepository userStatsRepository;
-
+	private final NotificationPublisher notificationPublisher;
+
 	/**
 	 * 기본 생성자 (Lambda에서 사용)
 	 */
 	public BadgeService() {
-		this(new BadgeRepository(), new UserStatsRepository());
+		this(new BadgeRepository(), new UserStatsRepository(), NotificationPublisher.getInstance());
 	}
-	
+
 	/**
 	 * 의존성 주입 생성자 (테스트 용이성)
 	 */
-	public BadgeService(BadgeRepository badgeRepository, UserStatsRepository userStatsRepository) {
+	public BadgeService(BadgeRepository badgeRepository, UserStatsRepository userStatsRepository,
+						NotificationPublisher notificationPublisher) {
 		this.badgeRepository = badgeRepository;
 		this.userStatsRepository = userStatsRepository;
+		this.notificationPublisher = notificationPublisher;
 	}
 
 	/**
@@ -98,6 +102,15 @@ public List<UserBadge> checkAndAwardBadges(String userId, UserStats stats) {
 				badgeRepository.save(badge);
 				newBadges.add(badge);
 				logger.info("Badge awarded: userId={}, badge={}", userId, type.name());
+
+				// 알림 발행
+				notificationPublisher.publishBadgeEarned(
+						userId,
+						type.name(),
+						type.getName(),
+						type.getDescription(),
+						badge.getImageUrl()
+				);
 			}
 		}
 

ServerlessFunction/src/main/java/com/mzc/secondproject/serverless/domain/chatting/service/GameService.java

@@ -13,6 +13,7 @@
 import com.mzc.secondproject.serverless.domain.chatting.repository.ConnectionRepository;
 import com.mzc.secondproject.serverless.domain.chatting.repository.GameRoundRepository;
 import com.mzc.secondproject.serverless.domain.chatting.repository.GameSessionRepository;
+import com.mzc.secondproject.serverless.domain.notification.service.NotificationPublisher;
 import com.mzc.secondproject.serverless.domain.vocabulary.model.Word;
 import com.mzc.secondproject.serverless.domain.vocabulary.repository.WordRepository;
 import org.slf4j.Logger;
@@ -37,30 +38,33 @@ public class GameService {
 	private final WordRepository wordRepository;
 	private final GameStatsService gameStatsService;
 	private final GameSchedulerClient gameSchedulerClient;
-
+	private final NotificationPublisher notificationPublisher;
+
 	/**
 	 * 기본 생성자 (Lambda에서 사용)
 	 */
 	public GameService() {
 		this(new ChatRoomRepository(), new ConnectionRepository(),
 				new GameRoundRepository(), new GameSessionRepository(),
-				new WordRepository(), new GameStatsService(), new GameSchedulerClient());
+				new WordRepository(), new GameStatsService(), new GameSchedulerClient(),
+				NotificationPublisher.getInstance());
 	}
-	
+
 	/**
 	 * 의존성 주입 생성자 (테스트 용이성)
 	 */
 	public GameService(ChatRoomRepository chatRoomRepository, ConnectionRepository connectionRepository,
 	                   GameRoundRepository gameRoundRepository, GameSessionRepository gameSessionRepository,
 	                   WordRepository wordRepository, GameStatsService gameStatsService,
-	                   GameSchedulerClient gameSchedulerClient) {
+	                   GameSchedulerClient gameSchedulerClient, NotificationPublisher notificationPublisher) {
 		this.chatRoomRepository = chatRoomRepository;
 		this.connectionRepository = connectionRepository;
 		this.gameRoundRepository = gameRoundRepository;
 		this.gameSessionRepository = gameSessionRepository;
 		this.wordRepository = wordRepository;
 		this.gameStatsService = gameStatsService;
 		this.gameSchedulerClient = gameSchedulerClient;
+		this.notificationPublisher = notificationPublisher;
 	}
 
 	/**
@@ -508,7 +512,10 @@ private CommandResult finishGame(GameSession session, ChatRoom room, String reas
 		} catch (Exception e) {
 			logger.error("Failed to update game stats: roomId={}, error={}", room.getRoomId(), e.getMessage());
 		}
-
+
+		// 게임 종료 알림 발행 (각 플레이어별)
+		publishGameEndNotifications(session, room.getRoomId());
+
 		// 최종 점수 정렬
 		StringBuilder sb = new StringBuilder("🎮 게임 종료!\n\n📊 최종 순위:\n");
 		if (session.getScores() != null && !session.getScores().isEmpty()) {
@@ -698,11 +705,11 @@ private List<Map<String, Object>> buildRankingList(Map<String, Integer> scores)
 		if (scores == null || scores.isEmpty()) {
 			return List.of();
 		}
-		
+
 		List<Map.Entry<String, Integer>> sorted = scores.entrySet().stream()
 				.sorted(Map.Entry.<String, Integer>comparingByValue().reversed())
 				.toList();
-		
+
 		List<Map<String, Object>> ranking = new ArrayList<>();
 		for (int i = 0; i < sorted.size(); i++) {
 			Map<String, Object> entry = new HashMap<>();
@@ -713,7 +720,39 @@ private List<Map<String, Object>> buildRankingList(Map<String, Integer> scores)
 		}
 		return ranking;
 	}
-
+
+	/**
+	 * 게임 종료 알림 발행
+	 */
+	private void publishGameEndNotifications(GameSession session, String roomId) {
+		if (session.getScores() == null || session.getScores().isEmpty()) {
+			return;
+		}
+
+		List<Map.Entry<String, Integer>> sorted = session.getScores().entrySet().stream()
+				.sorted((a, b) -> b.getValue().compareTo(a.getValue()))
+				.toList();
+
+		int totalPlayers = sorted.size();
+
+		for (int i = 0; i < sorted.size(); i++) {
+			int rank = i + 1;
+			String userId = sorted.get(i).getKey();
+			int score = sorted.get(i).getValue();
+			boolean isWinner = rank == 1;
+
+			notificationPublisher.publishGameEnd(
+					userId,
+					roomId,
+					session.getGameSessionId(),
+					rank,
+					totalPlayers,
+					score,
+					isWinner
+			);
+		}
+	}
+
 	// ========== Result DTOs ==========
 
 	public record GameStartResult(

ServerlessFunction/src/main/java/com/mzc/secondproject/serverless/domain/news/config/NewsConfig.java

@@ -0,0 +1,83 @@
+package com.mzc.secondproject.serverless.domain.news.config;
+
+import com.mzc.secondproject.serverless.common.config.EnvConfig;
+
+/**
+ * 뉴스 도메인 설정
+ * 상수 및 환경변수 관리
+ */
+public final class NewsConfig {
+
+	private NewsConfig() {
+	}
+
+	// ========== Environment Variables ==========
+	private static final String BUCKET_NAME = EnvConfig.getOrDefault("NEWS_BUCKET_NAME", "group2-englishstudy");
+
+	// ========== TTS 설정 ==========
+	/** TTS 텍스트 최대 길이 */
+	public static final int TTS_MAX_TEXT_LENGTH = 3000;
+
+	/** TTS 오디오 저장 경로 */
+	public static final String TTS_AUDIO_PREFIX = "news/audio/";
+
+	/** 기본 TTS 음성 */
+	public static final String DEFAULT_VOICE = "Joanna";
+
+	// ========== 페이지네이션 ==========
+	/** 기본 페이지 크기 */
+	public static final int DEFAULT_PAGE_SIZE = 10;
+
+	/** 최대 페이지 크기 */
+	public static final int MAX_PAGE_SIZE = 50;
+
+	// ========== 퀴즈 피드백 ==========
+	public static final String FEEDBACK_PERFECT = "Perfect! You understood the article completely.";
+	public static final String FEEDBACK_GREAT = "Great job! You have a solid understanding of the article.";
+	public static final String FEEDBACK_GOOD = "Good effort! Review the highlighted words for better comprehension.";
+	public static final String FEEDBACK_KEEP_PRACTICING = "Keep practicing! Try reading the article again before retaking the quiz.";
+	public static final String FEEDBACK_DONT_GIVE_UP = "Don't give up! Focus on vocabulary and main ideas.";
+
+	// ========== Score 기준 ==========
+	public static final int SCORE_PERFECT = 100;
+	public static final int SCORE_GREAT_THRESHOLD = 80;
+	public static final int SCORE_GOOD_THRESHOLD = 60;
+	public static final int SCORE_KEEP_PRACTICING_THRESHOLD = 40;
+
+	// ========== Getter Methods ==========
+	public static String bucketName() {
+		return BUCKET_NAME;
+	}
+
+	/**
+	 * 점수에 따른 피드백 생성
+	 */
+	public static String getFeedbackByScore(int score) {
+		if (score == SCORE_PERFECT) {
+			return FEEDBACK_PERFECT;
+		} else if (score >= SCORE_GREAT_THRESHOLD) {
+			return FEEDBACK_GREAT;
+		} else if (score >= SCORE_GOOD_THRESHOLD) {
+			return FEEDBACK_GOOD;
+		} else if (score >= SCORE_KEEP_PRACTICING_THRESHOLD) {
+			return FEEDBACK_KEEP_PRACTICING;
+		} else {
+			return FEEDBACK_DONT_GIVE_UP;
+		}
+	}
+
+	/**
+	 * limit 값 파싱 및 유효성 검증
+	 */
+	public static int parseLimit(String limitStr) {
+		if (limitStr == null) {
+			return DEFAULT_PAGE_SIZE;
+		}
+		try {
+			int limit = Integer.parseInt(limitStr);
+			return Math.min(Math.max(limit, 1), MAX_PAGE_SIZE);
+		} catch (NumberFormatException e) {
+			return DEFAULT_PAGE_SIZE;
+		}
+	}
+}

ServerlessFunction/src/main/java/com/mzc/secondproject/serverless/domain/news/constants/NewsKey.java

@@ -126,4 +126,16 @@ public static String userNewsCommentsPk(String userId) {
 	public static String userNewsStatPk(String userId) {
 		return "USER_NEWS_STAT#" + userId;
 	}
+
+	// === Utility Methods ===
+
+	/**
+	 * PK에서 날짜 추출 (NEWS#2024-01-15 → 2024-01-15)
+	 */
+	public static String extractDateFromPk(String pk) {
+		if (pk == null || !pk.startsWith(NEWS)) {
+			return null;
+		}
+		return pk.substring(NEWS.length());
+	}
 }