Merge pull request #295 from prgrms-web-devcourse-final-project/feat/chat-cache

채팅 기록 redis 캐시

Author: DooHyoJeong

backend/src/main/java/com/ai/lawyer/domain/chatbot/service/ChatBotService.java

@@ -6,8 +6,8 @@
 import com.ai.lawyer.domain.chatbot.dto.ChatDto.ChatResponse;
 import com.ai.lawyer.domain.chatbot.entity.History;
 import com.ai.lawyer.domain.chatbot.repository.HistoryRepository;
-import com.ai.lawyer.domain.kafka.dto.ChatPostProcessEvent;
-import com.ai.lawyer.domain.kafka.dto.DocumentDto;
+import com.ai.lawyer.infrastructure.kafka.dto.ChatPostProcessEvent;
+import com.ai.lawyer.infrastructure.kafka.dto.DocumentDto;
 import com.ai.lawyer.domain.member.entity.Member;
 import com.ai.lawyer.domain.member.repositories.MemberRepository;
 import com.ai.lawyer.global.qdrant.service.QdrantService;

backend/src/main/java/com/ai/lawyer/domain/chatbot/service/HistoryService.java

@@ -1,13 +1,14 @@
 package com.ai.lawyer.domain.chatbot.service;
 
-import com.ai.lawyer.domain.chatbot.dto.ChatDto;
+import com.ai.lawyer.domain.chatbot.dto.ChatDto.ChatHistoryDto;
 import com.ai.lawyer.domain.chatbot.dto.HistoryDto;
 import com.ai.lawyer.domain.chatbot.entity.Chat;
 import com.ai.lawyer.domain.chatbot.entity.History;
 import com.ai.lawyer.domain.chatbot.exception.HistoryNotFoundException;
 import com.ai.lawyer.domain.chatbot.repository.HistoryRepository;
 import com.ai.lawyer.domain.member.entity.Member;
 import com.ai.lawyer.domain.member.repositories.MemberRepository;
+import com.ai.lawyer.infrastructure.redis.service.ChatCacheService;
 import lombok.RequiredArgsConstructor;
 import org.springframework.http.ResponseEntity;
 import org.springframework.stereotype.Service;
@@ -20,6 +21,8 @@
 @RequiredArgsConstructor
 public class HistoryService {
 
+    private final ChatCacheService chatCacheService;
+
     private final HistoryRepository historyRepository;
     private final MemberRepository memberRepository;
 
@@ -54,20 +57,30 @@ public String deleteHistory(Long memberId, Long roomId) {
     }
 
     @Transactional(readOnly = true)
-    public ResponseEntity<List<ChatDto.ChatHistoryDto>> getChatHistory(Long memberId, Long roomId) {
+    public ResponseEntity<List<ChatHistoryDto>> getChatHistory(Long memberId, Long roomId) {
 
         Member member = memberRepository.findById(memberId).orElseThrow(
                 () -> new IllegalArgumentException("존재하지 않는 회원입니다.")
         );
 
-        List<Chat> chats = historyRepository.findByHistoryIdAndMemberId(roomId, member).getChats();
-        List<ChatDto.ChatHistoryDto> chatDtos = new ArrayList<>();
-
-        for (Chat chat : chats) {
-            ChatDto.ChatHistoryDto dto = ChatDto.ChatHistoryDto.from(chat);
-            chatDtos.add(dto);
+        // 1. Redis 캐시에서 조회 (있으면 바로 반환)
+        List<ChatHistoryDto> cached = chatCacheService.getChatHistory(roomId);
+        if (!cached.isEmpty()) {
+            return ResponseEntity.ok(cached);
         }
 
+        // 2. DB에서 조회 후 캐시에 저장
+        History history = historyRepository.findByHistoryIdAndMemberId(roomId, member);
+        List<Chat> chats = history.getChats();
+
+        // 엔티티 -> DTO 변환
+        List<ChatHistoryDto> chatDtos = chats.stream()
+                .map(ChatHistoryDto::from)
+                .toList();
+
+        // DB 조회 결과를 Redis 캐시에 저장
+        chatDtos.forEach(dto -> chatCacheService.cacheChatMessage(roomId, dto));
+
         return ResponseEntity.ok(chatDtos);
 
     }

backend/src/main/java/com/ai/lawyer/global/config/RedisConfig.java

@@ -1,5 +1,9 @@
 package com.ai.lawyer.global.config;
 
+import com.ai.lawyer.domain.chatbot.dto.ChatDto.ChatHistoryDto;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.SerializationFeature;
+import com.fasterxml.jackson.datatype.jsr310.JavaTimeModule;
 import lombok.extern.slf4j.Slf4j;
 import org.springframework.beans.factory.annotation.Value;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
@@ -10,6 +14,7 @@
 import org.springframework.data.redis.connection.RedisStandaloneConfiguration;
 import org.springframework.data.redis.connection.lettuce.LettuceConnectionFactory;
 import org.springframework.data.redis.core.RedisTemplate;
+import org.springframework.data.redis.serializer.GenericJackson2JsonRedisSerializer;
 import org.springframework.data.redis.serializer.StringRedisSerializer;
 
 @Slf4j
@@ -53,4 +58,25 @@ public RedisTemplate<String, Object> redisTemplate(RedisConnectionFactory redisC
         log.info("=== RedisTemplate 설정 완료 (host={}, port={}) ===", redisHost, redisPort);
         return redisTemplate;
     }
+
+    @Bean
+    public RedisTemplate<String, ChatHistoryDto> chatRedisTemplate(RedisConnectionFactory connectionFactory) {
+        RedisTemplate<String, ChatHistoryDto> template = new RedisTemplate<>();
+        template.setConnectionFactory(connectionFactory);
+
+        template.setKeySerializer(new StringRedisSerializer());
+
+        ObjectMapper mapper = new ObjectMapper();
+        mapper.registerModule(new JavaTimeModule());
+        mapper.disable(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS);
+        GenericJackson2JsonRedisSerializer serializer = new GenericJackson2JsonRedisSerializer(mapper);
+
+        template.setValueSerializer(serializer);
+        template.setHashValueSerializer(serializer);
+
+        template.afterPropertiesSet();
+        return template;
+    }
+
+
 }

backend/src/main/java/com/ai/lawyer/domain/kafka/consumer/ChatPostProcessingConsumer.java renamed to backend/src/main/java/com/ai/lawyer/infrastructure/kafka/consumer/ChatPostProcessingConsumer.java

@@ -1,12 +1,16 @@
-package com.ai.lawyer.domain.kafka.consumer;
+package com.ai.lawyer.infrastructure.kafka.consumer;
 
+import com.ai.lawyer.domain.chatbot.dto.ChatDto.ChatHistoryDto;
+import com.ai.lawyer.domain.chatbot.dto.ChatDto.ChatLawDto;
+import com.ai.lawyer.domain.chatbot.dto.ChatDto.ChatPrecedentDto;
 import com.ai.lawyer.domain.chatbot.dto.ExtractionDto.KeywordExtractionDto;
 import com.ai.lawyer.domain.chatbot.dto.ExtractionDto.TitleExtractionDto;
 import com.ai.lawyer.domain.chatbot.entity.*;
 import com.ai.lawyer.domain.chatbot.repository.*;
 import com.ai.lawyer.domain.chatbot.service.KeywordService;
-import com.ai.lawyer.domain.kafka.dto.ChatPostProcessEvent;
-import com.ai.lawyer.domain.kafka.dto.DocumentDto;
+import com.ai.lawyer.infrastructure.kafka.dto.ChatPostProcessEvent;
+import com.ai.lawyer.infrastructure.kafka.dto.DocumentDto;
+import com.ai.lawyer.infrastructure.redis.service.ChatCacheService;
 import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
 import org.springframework.ai.chat.memory.ChatMemory;
@@ -19,6 +23,7 @@
 import org.springframework.stereotype.Service;
 import org.springframework.transaction.annotation.Transactional;
 
+import java.util.ArrayList;
 import java.util.List;
 import java.util.stream.Collectors;
 
@@ -28,6 +33,8 @@
 public class ChatPostProcessingConsumer {
 
     private final KeywordService keywordService;
+    private final ChatCacheService chatCacheService;
+
     private final HistoryRepository historyRepository;
     private final ChatRepository chatRepository;
     private final KeywordRankRepository keywordRankRepository;
@@ -59,7 +66,7 @@ public void consume(ChatPostProcessEvent event) {
             // 2. 채팅방 제목 설정 / 및 필터
             setHistoryTitle(event.getUserMessage(), history, event.getChatResponse());
 
-            // 3. 채팅 기록 저장
+            // 3. 채팅 기록 저장 및 Redis 캐시 저장
             saveChatWithDocuments(history, MessageType.USER, event.getUserMessage(), event.getSimilarCaseDocuments(), event.getSimilarLawDocuments());
             saveChatWithDocuments(history, MessageType.ASSISTANT, event.getChatResponse(), event.getSimilarCaseDocuments(), event.getSimilarLawDocuments());
 
@@ -99,6 +106,10 @@ private void extractAndUpdateKeywordRanks(String message) {
     }
 
     private void saveChatWithDocuments(History history, MessageType type, String message, List<DocumentDto> similarCaseDocuments, List<DocumentDto> similarLawDocuments) {
+
+        List<ChatPrecedent> chatPrecedents = new ArrayList<>();
+        List<ChatLaw> chatLaws = new ArrayList<>();
+
         Chat chat = chatRepository.save(Chat.builder()
                 .historyId(history)
                 .type(type)
@@ -108,7 +119,7 @@ private void saveChatWithDocuments(History history, MessageType type, String mes
         // Ai 메시지가 저장될 때 관련 문서 저장
         if (type == MessageType.ASSISTANT) {
             if (similarCaseDocuments != null && !similarCaseDocuments.isEmpty()) {
-                List<ChatPrecedent> chatPrecedents = similarCaseDocuments.stream()
+                chatPrecedents = similarCaseDocuments.stream()
                         .map(doc -> ChatPrecedent.builder()
                                 .chatId(chat)
                                 .precedentContent(doc.getText())
@@ -120,7 +131,7 @@ private void saveChatWithDocuments(History history, MessageType type, String mes
             }
 
             if (similarLawDocuments != null && !similarLawDocuments.isEmpty()) {
-                List<ChatLaw> chatLaws = similarLawDocuments.stream()
+                chatLaws = similarLawDocuments.stream()
                         .map(doc -> ChatLaw.builder()
                                 .chatId(chat)
                                 .content(doc.getText())
@@ -130,5 +141,16 @@ private void saveChatWithDocuments(History history, MessageType type, String mes
                 chatLawRepository.saveAll(chatLaws);
             }
         }
+
+        // Redis 캐시에 DTO 저장
+        ChatHistoryDto dto = ChatHistoryDto.builder()
+                .type(type.toString())
+                .message(message)
+                .createdAt(chat.getCreatedAt())
+                .precedent(chatPrecedents.isEmpty() ? null : ChatPrecedentDto.from(chatPrecedents.get(0)))
+                .law(chatLaws.isEmpty() ? null : ChatLawDto.from(chatLaws.get(0)))
+                .build();
+
+        chatCacheService.cacheChatMessage(history.getHistoryId(), dto);
     }
 }

backend/src/main/java/com/ai/lawyer/domain/kafka/dto/ChatPostProcessEvent.java renamed to backend/src/main/java/com/ai/lawyer/infrastructure/kafka/dto/ChatPostProcessEvent.java

@@ -1,4 +1,4 @@
-package com.ai.lawyer.domain.kafka.dto;
+package com.ai.lawyer.infrastructure.kafka.dto;
 
 import lombok.AllArgsConstructor;
 import lombok.Data;

backend/src/main/java/com/ai/lawyer/domain/kafka/dto/DocumentDto.java renamed to backend/src/main/java/com/ai/lawyer/infrastructure/kafka/dto/DocumentDto.java

@@ -1,4 +1,4 @@
-package com.ai.lawyer.domain.kafka.dto;
+package com.ai.lawyer.infrastructure.kafka.dto;
 
 import lombok.AllArgsConstructor;
 import lombok.Data;

backend/src/main/java/com/ai/lawyer/infrastructure/redis/service/ChatCacheService.java

@@ -0,0 +1,35 @@
+package com.ai.lawyer.infrastructure.redis.service;
+
+import com.ai.lawyer.domain.chatbot.dto.ChatDto.ChatHistoryDto;
+import lombok.RequiredArgsConstructor;
+import org.springframework.data.redis.core.RedisTemplate;
+import org.springframework.stereotype.Service;
+
+import java.time.Duration;
+import java.util.List;
+
+@Service
+@RequiredArgsConstructor
+public class ChatCacheService {
+
+    private final RedisTemplate<String, ChatHistoryDto> chatRedisTemplate; // 새 템플릿 사용
+    private static final String CHAT_HISTORY_KEY_PREFIX = "chat:history:";
+
+    // 채팅 메시지 캐싱 (24시간)
+    public void cacheChatMessage(Long roomId, ChatHistoryDto chatHistory) {
+        String key = CHAT_HISTORY_KEY_PREFIX + roomId;
+        chatRedisTemplate.opsForList().rightPush(key, chatHistory);
+        chatRedisTemplate.expire(key, Duration.ofHours(24));
+    }
+
+    public List<ChatHistoryDto> getChatHistory(Long roomId) {
+        String key = CHAT_HISTORY_KEY_PREFIX + roomId;
+        List<ChatHistoryDto> cachedList = chatRedisTemplate.opsForList().range(key, 0, -1);
+        return cachedList == null ? List.of() : cachedList;
+    }
+
+    public void clearChatHistory(Long roomId) {
+        chatRedisTemplate.delete(CHAT_HISTORY_KEY_PREFIX + roomId);
+    }
+
+}