feat: fetch user chatroom detail

src/main/java/toy/bookchat/bookchat/domain/chatroom/api/ChatRoomController.java

@@ -14,6 +14,7 @@
 import org.springframework.web.bind.annotation.RequestPart;
 import org.springframework.web.bind.annotation.RestController;
 import org.springframework.web.multipart.MultipartFile;
+import toy.bookchat.bookchat.domain.chatroom.api.dto.response.UserChatRoomDetailResponse;
 import toy.bookchat.bookchat.domain.chatroom.repository.query.dto.response.ChatRoomsResponseSlice;
 import toy.bookchat.bookchat.domain.chatroom.repository.query.dto.response.UserChatRoomsResponseSlice;
 import toy.bookchat.bookchat.domain.chatroom.service.ChatRoomService;
@@ -51,6 +52,11 @@ public UserChatRoomsResponseSlice getUserChatRooms(Long bookId, Long postCursorI
         return chatRoomService.getUserChatRooms(bookId, postCursorId, pageable, tokenPayload.getUserId());
     }
 
+    @GetMapping("/users/chatrooms/{roomId}")
+    public UserChatRoomDetailResponse getUserChatRoomDetails(@PathVariable Long roomId, @UserPayload TokenPayload tokenPayload) {
+        return chatRoomService.getUserChatRoomDetails(roomId, tokenPayload.getUserId());
+    }
+
     @GetMapping("/chatrooms")
     public ChatRoomsResponseSlice getChatRooms(@ModelAttribute ChatRoomRequest chatRoomRequest, Pageable pageable) {
         chatRoomRequest.validate();

src/main/java/toy/bookchat/bookchat/domain/chatroom/api/dto/response/UserChatRoomDetailResponse.java

@@ -0,0 +1,37 @@
+package toy.bookchat.bookchat.domain.chatroom.api.dto.response;
+
+import lombok.Builder;
+import lombok.Getter;
+import toy.bookchat.bookchat.domain.chatroom.ChatRoom;
+
+@Getter
+public class UserChatRoomDetailResponse {
+
+    private Long roomId;
+    private String roomName;
+    private String roomSid;
+    private Long roomMemberCount;
+    private String roomImageUri;
+    private Integer defaultRoomImageType;
+
+    @Builder
+    private UserChatRoomDetailResponse(Long roomId, String roomName, String roomSid, Long roomMemberCount, String roomImageUri, Integer defaultRoomImageType) {
+        this.roomId = roomId;
+        this.roomName = roomName;
+        this.roomSid = roomSid;
+        this.roomImageUri = roomImageUri;
+        this.defaultRoomImageType = defaultRoomImageType;
+        this.roomMemberCount = roomMemberCount;
+    }
+
+    public static UserChatRoomDetailResponse from(ChatRoom chatroom, Long roomMemberCount) {
+        return UserChatRoomDetailResponse.builder()
+            .roomId(chatroom.getId())
+            .roomName(chatroom.getRoomName())
+            .roomSid(chatroom.getRoomSid())
+            .roomImageUri(chatroom.getRoomImageUri())
+            .defaultRoomImageType(chatroom.getDefaultRoomImageType())
+            .roomMemberCount(roomMemberCount)
+            .build();
+    }
+}

src/main/java/toy/bookchat/bookchat/domain/chatroom/repository/query/ChatRoomQueryRepository.java

@@ -1,7 +1,9 @@
 package toy.bookchat.bookchat.domain.chatroom.repository.query;
 
+import java.util.Optional;
 import org.springframework.data.domain.Pageable;
 import org.springframework.data.domain.Slice;
+import toy.bookchat.bookchat.domain.chatroom.ChatRoom;
 import toy.bookchat.bookchat.domain.chatroom.repository.query.dto.response.ChatRoomResponse;
 import toy.bookchat.bookchat.domain.chatroom.repository.query.dto.response.UserChatRoomResponse;
 import toy.bookchat.bookchat.domain.chatroom.service.dto.request.ChatRoomRequest;
@@ -15,4 +17,6 @@ public interface ChatRoomQueryRepository {
     Slice<ChatRoomResponse> findChatRooms(ChatRoomRequest chatRoomRequest, Pageable pageable);
 
     ChatRoomDetails findChatRoomDetails(Long roomId, Long userId);
+
+    Optional<ChatRoom> findUserChatRoom(Long roomId, Long userId);
 }

src/main/java/toy/bookchat/bookchat/domain/chatroom/repository/query/ChatRoomQueryRepositoryImpl.java

@@ -18,6 +18,7 @@
 import com.querydsl.jpa.impl.JPAQueryFactory;
 import java.util.List;
 import java.util.Map;
+import java.util.Optional;
 import org.springframework.data.domain.Pageable;
 import org.springframework.data.domain.Slice;
 import org.springframework.stereotype.Repository;
@@ -220,4 +221,13 @@ public ChatRoomDetails findChatRoomDetails(Long roomId, Long userId) {
 
         return ChatRoomDetails.from(participants, roomTags);
     }
+
+    @Override
+    public Optional<ChatRoom> findUserChatRoom(Long roomId, Long userId) {
+        return Optional.ofNullable(queryFactory.select(chatRoom)
+            .from(chatRoom)
+            .join(participant).on(participant.chatRoom.eq(chatRoom).and(participant.user.id.eq(userId)))
+            .where(chatRoom.id.eq(roomId))
+            .fetchOne());
+    }
 }

src/main/java/toy/bookchat/bookchat/domain/chatroom/service/ChatRoomService.java

@@ -20,6 +20,7 @@
 import toy.bookchat.bookchat.domain.chatroom.ChatRoom;
 import toy.bookchat.bookchat.domain.chatroom.ChatRoomHashTag;
 import toy.bookchat.bookchat.domain.chatroom.HashTag;
+import toy.bookchat.bookchat.domain.chatroom.api.dto.response.UserChatRoomDetailResponse;
 import toy.bookchat.bookchat.domain.chatroom.repository.ChatRoomBlockedUserRepository;
 import toy.bookchat.bookchat.domain.chatroom.repository.ChatRoomHashTagRepository;
 import toy.bookchat.bookchat.domain.chatroom.repository.ChatRoomRepository;
@@ -124,6 +125,14 @@ public UserChatRoomsResponseSlice getUserChatRooms(Long bookId, Long postCursorI
         return UserChatRoomsResponseSlice.of(chatRoomRepository.findUserChatRoomsWithLastChat(pageable, bookId, postCursorId, userId));
     }
 
+    @Transactional(readOnly = true)
+    public UserChatRoomDetailResponse getUserChatRoomDetails(Long roomId, Long userId) {
+        ChatRoom chatroom = chatRoomRepository.findUserChatRoom(roomId, userId).orElseThrow(ChatRoomNotFoundException::new);
+        Long roomMemberCount = participantRepository.countByChatRoom(chatroom);
+
+        return UserChatRoomDetailResponse.from(chatroom, roomMemberCount);
+    }
+
     @Transactional(readOnly = true)
     public ChatRoomsResponseSlice getChatRooms(ChatRoomRequest chatRoomRequest, Pageable pageable) {
         return ChatRoomsResponseSlice.of(chatRoomRepository.findChatRooms(chatRoomRequest, pageable));
@@ -225,4 +234,5 @@ public void exitChatRoom(Long userId, Long roomId) {
         participantRepository.delete(participant);
         messagePublisher.sendNotificationMessage(chatRoom.getRoomSid(), NotificationMessage.createExitMessage(chat, user.getId()));
     }
+
 }

src/main/java/toy/bookchat/bookchat/domain/participant/repository/ParticipantRepository.java

@@ -15,4 +15,6 @@ public interface ParticipantRepository extends ParticipantQueryRepository,
     List<Participant> findWithPessimisticLockByChatRoom(ChatRoom chatRoom);
 
     void deleteByChatRoom(ChatRoom chatRoom);
+
+    Long countByChatRoom(ChatRoom chatroom);
 }