feat: WebSocket으로 채팅 기능(만) 완료 #81

be/build.gradle

@@ -69,7 +69,7 @@ dependencies {
 
     // webSocket
     implementation 'org.springframework.boot:spring-boot-starter-websocket'
-    implementation 'org.webjars:stomp-websocket'
+    implementation 'org.webjars:stomp-websocket:2.3.4'
 }
 
 tasks.named('test') {

be/src/main/java/kr/codesquad/chat/controller/ChatController.java

@@ -8,7 +8,8 @@
 import org.springframework.web.bind.annotation.RequestBody;
 import org.springframework.web.bind.annotation.RestController;
 
-import kr.codesquad.chat.dto.ChatRoomCreateRequest;
+import kr.codesquad.chat.dto.request.ChatRoomCreateRequest;
+import kr.codesquad.chat.dto.response.ChatRoomCreateResponse;
 import kr.codesquad.chat.service.ChatService;
 import kr.codesquad.util.Constants;
 import lombok.RequiredArgsConstructor;
@@ -19,12 +20,13 @@ public class ChatController {
 
 	private final ChatService chatService;
 
-	@PostMapping("/")
-	public ResponseEntity<Void> createChatRoom(@RequestBody ChatRoomCreateRequest chatRoomCreateRequest,
+	@PostMapping("/api/chat")
+	public ResponseEntity<ChatRoomCreateResponse> createChatRoom(
+		@RequestBody ChatRoomCreateRequest chatRoomCreateRequest,
 		HttpServletRequest request) {
 		String loginId = (String)request.getAttribute(Constants.LOGIN_ID);
-		chatService.createRoom(chatRoomCreateRequest, loginId);
-		return ResponseEntity.status(HttpStatus.CREATED).build();
+		return ResponseEntity.status(HttpStatus.CREATED)
+			.body(chatService.createRoom(chatRoomCreateRequest, loginId));
 	}
 
 }

be/src/main/java/kr/codesquad/chat/dto/ChatMapper.java

@@ -4,6 +4,8 @@
 import org.mapstruct.Mapping;
 import org.mapstruct.factory.Mappers;
 
+import kr.codesquad.chat.dto.request.ChatRoomCreateRequest;
+import kr.codesquad.chat.dto.response.ChatRoomCreateResponse;
 import kr.codesquad.chat.entity.ChatRoom;
 
 @Mapper
@@ -12,4 +14,7 @@ public interface ChatMapper {
 
 	@Mapping(target = "senderId", source = "userId")
 	ChatRoom toChatRoom(ChatRoomCreateRequest chatRoomCreateRequest, Long userId);
+
+	@Mapping(target = "chatRoomId", source = "id")
+	ChatRoomCreateResponse toChatRoomCreateResponse(ChatRoom chatRoom);
 }

be/src/main/java/kr/codesquad/chat/dto/ChatRoomCreateRequest.java → be/src/main/java/kr/codesquad/chat/dto/request/ChatRoomCreateRequest.java

@@ -1,4 +1,4 @@
-package kr.codesquad.chat.dto;
+package kr.codesquad.chat.dto.request;
 
 import lombok.Getter;
 

be/src/main/java/kr/codesquad/chat/dto/request/SendMessageRequest.java

@@ -0,0 +1,20 @@
+package kr.codesquad.chat.dto.request;
+
+import lombok.Builder;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+
+@Getter
+@NoArgsConstructor
+public class SendMessageRequest {
+	private Long chatRoomId;
+	private Long senderId;
+	private String content;
+
+	@Builder
+	public SendMessageRequest(Long chatRoomId, Long senderId, String content) {
+		this.chatRoomId = chatRoomId;
+		this.senderId = senderId;
+		this.content = content;
+	}
+}

be/src/main/java/kr/codesquad/chat/dto/response/ChatRoomCreateResponse.java

@@ -0,0 +1,10 @@
+package kr.codesquad.chat.dto.response;
+
+import lombok.Builder;
+import lombok.Getter;
+
+@Getter
+@Builder
+public class ChatRoomCreateResponse {
+	private final Long chatRoomId;
+}

be/src/main/java/kr/codesquad/chat/service/ChatService.java

@@ -1,26 +1,61 @@
 package kr.codesquad.chat.service;
 
+import java.io.IOException;
+import java.util.HashSet;
+import java.util.Set;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.ConcurrentMap;
+
 import org.springframework.stereotype.Service;
+import org.springframework.web.socket.TextMessage;
+import org.springframework.web.socket.WebSocketSession;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
 
 import kr.codesquad.chat.dto.ChatMapper;
-import kr.codesquad.chat.dto.ChatRoomCreateRequest;
+import kr.codesquad.chat.dto.request.ChatRoomCreateRequest;
+import kr.codesquad.chat.dto.request.SendMessageRequest;
+import kr.codesquad.chat.dto.response.ChatRoomCreateResponse;
 import kr.codesquad.chat.repository.ChatMessageRepository;
 import kr.codesquad.chat.repository.ChatRoomRepository;
 import kr.codesquad.user.entity.User;
 import kr.codesquad.user.repository.UserRepository;
 import lombok.RequiredArgsConstructor;
+import lombok.extern.slf4j.Slf4j;
 
+@Slf4j
 @RequiredArgsConstructor
 @Service
 public class ChatService {
 
 	private final ChatRoomRepository chatRoomRepository;
 	private final ChatMessageRepository chatMessageRepository;
 	private final UserRepository userRepository;
+	private final ObjectMapper objectMapper;
+	private final ConcurrentMap<Long, Set<WebSocketSession>> sessionMap = new ConcurrentHashMap<>();
 
-	public void createRoom(ChatRoomCreateRequest chatRoomCreateRequest, String loginId) {
+	public ChatRoomCreateResponse createRoom(ChatRoomCreateRequest chatRoomCreateRequest, String loginId) {
 		User user = userRepository.findByLoginId(loginId);
-		chatRoomRepository.save(ChatMapper.INSTANCE.toChatRoom(chatRoomCreateRequest, user.getId()));
+		return ChatMapper.INSTANCE.toChatRoomCreateResponse(
+			chatRoomRepository.save(ChatMapper.INSTANCE.toChatRoom(chatRoomCreateRequest, user.getId())));
+	}
+
+	public void sendMessage(Long chatRoomId, WebSocketSession session, SendMessageRequest message) {
+		if (!sessionMap.containsKey(chatRoomId)) {
+			sessionMap.put(chatRoomId, new HashSet<>());
+		}
+		Set<WebSocketSession> sessions = sessionMap.get(chatRoomId);
+		sessions.add(session);
+		sessionMap.put(chatRoomId, sessions);
+		sessions.parallelStream().forEach(s -> sendMessage(s, message));
+	}
+
+	private <T> void sendMessage(WebSocketSession session, T message) {
+		try {
+			session.sendMessage(new TextMessage(objectMapper.writeValueAsString(message)));
+		} catch (IOException e) {
+			log.error(e.getMessage(), e);
+		}
 	}
 
 }

be/src/main/java/kr/codesquad/core/websocket/WebSocketHandler.java

@@ -7,6 +7,8 @@
 
 import com.fasterxml.jackson.databind.ObjectMapper;
 
+import kr.codesquad.chat.dto.request.SendMessageRequest;
+import kr.codesquad.chat.service.ChatService;
 import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
 
@@ -15,16 +17,15 @@
 @RequiredArgsConstructor
 public class WebSocketHandler extends TextWebSocketHandler {
 
-	private final MsgService msgService;
+	private final ChatService chatService;
 	private final ObjectMapper objectMapper;
 
 	@Override
 	protected void handleTextMessage(WebSocketSession session, TextMessage message) throws Exception {
 		String payload = message.getPayload();
 		log.info("payload:{}", payload);
 
-		Message msg = objectMapper.readValue(payload, Message.class);
-		MsgRoom room = msgService.findById(msg.getRoomId());
-		room.handleActions(session, msg, msgService);
+		SendMessageRequest msg = objectMapper.readValue(payload, SendMessageRequest.class);
+		chatService.sendMessage(msg.getChatRoomId(), session, msg);
 	}
 }

be/src/main/java/kr/codesquad/item/repository/ItemPaginationRepository.java

@@ -1,6 +1,6 @@
 package kr.codesquad.item.repository;
 
-import static kr.codesquad.chat.entity.QChat.*;
+import static kr.codesquad.chat.entity.QChatRoom.*;
 import static kr.codesquad.favorite.entity.QFavorite.*;
 import static kr.codesquad.item.entity.QItem.*;
 
@@ -33,12 +33,12 @@ public List<ItemListVo> readByConditions(ItemConditions itemConditions) {
 				item.createdAt,
 				item.price,
 				item.status,
-				chat.countDistinct().as("chat"),
+				chatRoom.countDistinct().as("chat"),
 				favorite.countDistinct().as("favorite"),
 				item.userId
 			))
 			.from(item)
-			.leftJoin(chat).on(item.id.eq(chat.itemId))
+			.leftJoin(chatRoom).on(item.id.eq(chatRoom.itemId))
 			.leftJoin(favorite).on(item.id.eq(favorite.itemId))
 			.where(lessThanItemId(itemConditions.getItemId()), equalLocationName(itemConditions.getLocationName())
 				, equalCategoryId(itemConditions.getCategoryId()), checkStatus(itemConditions.getIsSold())