Merge pull request #85 from Seeds-kr/feature/GroupChat-PastChat

그룹채팅 과거 기록 읽음 구현

Author: prin81208

LifeMaster-BE/src/main/java/com/example/LifeMaster_BE/Group/GroupChat/GroupChatDto.java

@@ -18,6 +18,16 @@ public static class ChatMessage {
         private String senderName;
         private String message;
         private LocalDateTime timestamp;
+        public static ChatMessage from(GroupChatEntity entity) {
+            return ChatMessage.builder()
+                    .id(entity.getId())
+                    .groupId(entity.getGroup().getId())
+                    .senderId(entity.getSender().getId())
+                    .senderName(entity.getSender().getNickname())
+                    .message(entity.getMessage())
+                    .timestamp(entity.getTimestamp())
+                    .build();
+        }
     }
 
     @Builder(toBuilder = true)

LifeMaster-BE/src/main/java/com/example/LifeMaster_BE/Group/GroupChat/GroupChatQueryController.java

@@ -0,0 +1,22 @@
+package com.example.LifeMaster_BE.Group.GroupChat;
+
+import lombok.RequiredArgsConstructor;
+import org.springframework.web.bind.annotation.*;
+
+import java.util.List;
+
+@RestController
+@RequiredArgsConstructor
+@RequestMapping("/groups")
+public class GroupChatQueryController {
+
+    private final GroupChatService chatService;
+
+    // 채팅방 최초 로딩용
+    @GetMapping("/{groupId}/chats")
+    public List<GroupChatDto.ChatMessage> getChats(
+            @PathVariable Long groupId
+    ) {
+        return chatService.getChatsByGroup(groupId);
+    }
+}

LifeMaster-BE/src/main/java/com/example/LifeMaster_BE/Group/GroupChat/GroupChatRepository.java

@@ -2,5 +2,8 @@
 
 import org.springframework.data.jpa.repository.JpaRepository;
 
+import java.util.List;
+
 public interface GroupChatRepository extends JpaRepository<GroupChatEntity, Long> {
+    List<GroupChatEntity> findByGroupIdOrderByTimestampAsc(Long groupId);
 }

LifeMaster-BE/src/main/java/com/example/LifeMaster_BE/Group/GroupChat/GroupChatService.java

@@ -6,6 +6,8 @@
 import org.springframework.stereotype.Service;
 
 import java.time.LocalDateTime;
+import java.util.List;
+import java.util.stream.Collectors;
 
 @Service
 @RequiredArgsConstructor
@@ -40,4 +42,12 @@ public void markAsRead(Long messageId, MemberEntity reader) {
             chatMessageRepository.save(messageEntity);
         });
     }
+
+    public List<GroupChatDto.ChatMessage> getChatsByGroup(Long groupId) {
+        return chatMessageRepository
+                .findByGroupIdOrderByTimestampAsc(groupId)
+                .stream()
+                .map(GroupChatDto.ChatMessage::from)
+                .collect(Collectors.toList());
+    }
 }