[FEAT] Chatbot ver.1 개발 (#89)

* [FEATURE] 챗봇 엔티티 생성

* [FEATURE] 메시지 전송 dto 구현

* [FEATURE] 메시지 응답 dto 구현

* [FEATURE] repository 구현

* [FEATURE] 세션 만드는 createSession, 메시지 전송하고 응답 받는 createMessage 메소드 구현

* [FEATURE] OpenAI API와 통신하면서 세션을 만들거나, 메시지에 대한 응답을 받는 메소드들 구현

* [STYLE] 코드 포맷팅

src/main/java/com/fav/daengnyang/domain/chatbot/controller/ChatbotController.java

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+package com.fav.daengnyang.domain.chatbot.controller;
+
+import com.fav.daengnyang.domain.chatbot.service.ChatbotService;
+import com.fav.daengnyang.domain.chatbot.service.dto.request.CreateMessageRequest;
+import com.fav.daengnyang.domain.chatbot.service.dto.response.MessageResponse;
+import com.fav.daengnyang.global.auth.dto.MemberPrincipal;
+import com.fav.daengnyang.global.dto.response.ExceptionResponse;
+import com.fav.daengnyang.global.web.dto.response.SuccessResponse;
+import jakarta.validation.Valid;
+import lombok.RequiredArgsConstructor;
+import org.springframework.security.core.annotation.AuthenticationPrincipal;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.RequestBody;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
+
+@RequiredArgsConstructor
+@RequestMapping("/chatbots")
+@RestController
+public class ChatbotController {
+
+    private final ChatbotService chatbotService;
+
+    // 챗봇에게 메시지 보내고 응답 받기
+    @PostMapping
+    public SuccessResponse<?> createMessage(
+            @AuthenticationPrincipal MemberPrincipal memberPrincipal,
+            @Valid @RequestBody CreateMessageRequest messageRequest
+    ) throws InterruptedException {
+        MessageResponse response = chatbotService.getMessage(memberPrincipal.getMemberId(), messageRequest);
+        return SuccessResponse.ok(response);
+    }
+
+    // 챗봇에게 처음 메시지 보내기(새로운 세션 만들기)
+    @PostMapping("/session")
+    public SuccessResponse<?> createSession(
+            @AuthenticationPrincipal MemberPrincipal memberPrincipal
+    ){
+        chatbotService.createSession(memberPrincipal.getMemberId());
+        return SuccessResponse.created("세션 생성에 성공했습니다.");
+    }
+}

src/main/java/com/fav/daengnyang/domain/chatbot/entity/Chatbot.java

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+package com.fav.daengnyang.domain.chatbot.entity;
+
+import jakarta.persistence.*;
+import lombok.Builder;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import lombok.Setter;
+
+@Entity
+@Table(name = "chatbot")
+@Getter
+@Setter
+@NoArgsConstructor
+public class Chatbot {
+
+    @Id
+    @Column(name = "member_id")
+    private Long memberId;
+
+    @Column(name = "thread_id")
+    private String threadId;
+
+    @Builder
+    public Chatbot(Long memberId, String threadId) {
+        this.memberId = memberId;
+        this.threadId = threadId;
+    }
+}

src/main/java/com/fav/daengnyang/domain/chatbot/repository/ChatbotRepository.java

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+package com.fav.daengnyang.domain.chatbot.repository;
+
+import com.fav.daengnyang.domain.chatbot.entity.Chatbot;
+import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.stereotype.Repository;
+
+@Repository
+public interface ChatbotRepository extends JpaRepository<Chatbot, Long> {
+}

src/main/java/com/fav/daengnyang/domain/chatbot/service/ChatbotService.java

@@ -0,0 +1,190 @@
+package com.fav.daengnyang.domain.chatbot.service;
+
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fav.daengnyang.domain.chatbot.entity.Chatbot;
+import com.fav.daengnyang.domain.chatbot.repository.ChatbotRepository;
+import com.fav.daengnyang.domain.chatbot.service.dto.request.CreateMessageRequest;
+import com.fav.daengnyang.domain.chatbot.service.dto.response.MessageResponse;
+import lombok.RequiredArgsConstructor;
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.http.HttpEntity;
+import org.springframework.http.HttpHeaders;
+import org.springframework.http.HttpMethod;
+import org.springframework.http.ResponseEntity;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+import org.springframework.web.client.RestTemplate;
+
+import java.util.ArrayList;
+import java.util.List;
+
+@Service
+@RequiredArgsConstructor
+@Transactional
+public class ChatbotService {
+
+    private final ChatbotRepository chatbotRepository;
+
+    // GPT API 키
+    @Value("${gpt-key}")
+    private String gptKey;
+
+    // assistant ID
+    @Value(("${assistant-id}"))
+    private String assistantId;
+
+    // 유저의 메시지에 대한 응답 받기
+    public MessageResponse getMessage(Long memberId, CreateMessageRequest messageRequest) throws InterruptedException {
+        String threadId = getThreadId(memberId);
+        sendMessage(threadId, messageRequest.getChat());
+        runMessages(threadId, assistantId);
+        Thread.sleep(1500);
+        List<String> messages = getMessageTextValues(threadId);
+        MessageResponse response = MessageResponse.builder()
+                .chat(messages.get(0))
+                .build();
+        return response;
+    }
+
+    // 세션 생성하면서 첫 메시지 보내는 메소드
+    public void createSession(Long memberId) {
+        chatbotRepository.deleteById(memberId);
+        getThreadId(memberId);
+    }
+
+    // 지금 스레드(세션) id 가져오기
+    private String getThreadId(Long memberId) {
+        try {
+            Chatbot chatbot = chatbotRepository.findById(memberId).orElseThrow(Exception::new);
+            return chatbot.getThreadId();
+        } catch (Exception e){
+            String thread = createThreadId();
+            Chatbot chatbot = new Chatbot();
+            chatbot.setThreadId(thread);
+            chatbot.setMemberId(memberId);
+            chatbotRepository.save(chatbot);
+            return thread;
+        }
+    }
+
+    // 새로운 스레드(세션 만들기)
+    private String createThreadId() {
+        String URL = "https://api.openai.com/v1/threads";
+        try {
+            // HTTP 요청 설정
+            RestTemplate restTemplate = new RestTemplate();
+            HttpHeaders headers = new HttpHeaders();
+            headers.set("Content-Type", "application/json");
+            headers.set("Authorization", "Bearer " + gptKey);
+            headers.set("OpenAI-Beta", "assistants=v2");
+            HttpEntity<String> entity = new HttpEntity<>("", headers);
+
+            // API 호출
+            ResponseEntity<String> response = restTemplate.exchange(URL, HttpMethod.POST, entity, String.class);
+            String jsonResponse = response.getBody();
+
+            // JSON 응답에서 id 추출
+            ObjectMapper objectMapper = new ObjectMapper();
+            JsonNode rootNode = objectMapper.readTree(jsonResponse);
+            return rootNode.path("id").asText();
+        } catch (Exception e) {
+            e.printStackTrace();
+            return null;
+        }
+    }
+
+    // 메시지 전송하기
+    private void sendMessage(String threadId, String messageContent) {
+        String BASE_URL = "https://api.openai.com/v1/threads/";
+        try {
+            // HTTP 요청 설정
+            RestTemplate restTemplate = new RestTemplate();
+            HttpHeaders headers = new HttpHeaders();
+            headers.set("Content-Type", "application/json");
+            headers.set("Authorization", "Bearer " + gptKey);
+            headers.set("OpenAI-Beta", "assistants=v2");
+
+            // 요청 바디 설정
+            String requestBody = String.format(
+                    "{\"role\": \"user\", \"content\": \"%s\"}",
+                    messageContent
+            );
+            HttpEntity<String> entity = new HttpEntity<>(requestBody, headers);
+
+            // API 호출
+            String url = BASE_URL + threadId + "/messages";
+            restTemplate.exchange(url, HttpMethod.POST, entity, String.class);
+        } catch (Exception e) {
+            e.printStackTrace();
+            return;
+        }
+    }
+
+    // 메시지를 GPT에서 동작시킴
+    private void runMessages(String threadId, String assistantId) {
+        String BASE_URL = "https://api.openai.com/v1/threads/";
+        try {
+            // HTTP 요청 설정
+            RestTemplate restTemplate = new RestTemplate();
+            HttpHeaders headers = new HttpHeaders();
+            headers.set("Authorization", "Bearer " + gptKey);
+            headers.set("Content-Type", "application/json");
+            headers.set("OpenAI-Beta", "assistants=v2");
+
+            // 요청 바디 설정
+            String requestBody = String.format(
+                    "{\"assistant_id\": \"%s\"}",
+                    assistantId
+            );
+            HttpEntity<String> entity = new HttpEntity<>(requestBody, headers);
+
+            // API 호출
+            String url = BASE_URL + threadId + "/runs";
+            restTemplate.exchange(url, HttpMethod.POST, entity, String.class);
+        } catch (Exception e) {
+            e.printStackTrace();
+            return;
+        }
+    }
+
+    // Message의 Text를 받아서 반환하는 메소드
+    private List<String> getMessageTextValues(String threadId) {
+        String BASE_URL = "https://api.openai.com/v1/threads/";
+        try {
+            // HTTP 요청 설정
+            RestTemplate restTemplate = new RestTemplate();
+            HttpHeaders headers = new HttpHeaders();
+            headers.set("Content-Type", "application/json");
+            headers.set("Authorization", "Bearer " + gptKey);
+            headers.set("OpenAI-Beta", "assistants=v2");
+
+            HttpEntity<String> entity = new HttpEntity<>(null, headers);
+
+            // API 호출
+            String url = BASE_URL + threadId + "/messages";
+            ResponseEntity<String> response = restTemplate.exchange(url, HttpMethod.GET, entity, String.class);
+
+            // 응답 처리
+            String jsonResponse = response.getBody();
+            ObjectMapper objectMapper = new ObjectMapper();
+            JsonNode rootNode = objectMapper.readTree(jsonResponse);
+            List<String> textValues = new ArrayList<>();
+
+            // 메시지에서 text value 추출
+            for (JsonNode messageNode : rootNode.path("data")) {
+                for (JsonNode contentNode : messageNode.path("content")) {
+                    if (contentNode.path("type").asText().equals("text")) {
+                        String textValue = contentNode.path("text").path("value").asText();
+                        textValues.add(textValue);
+                    }
+                }
+            }
+
+            return textValues;
+        } catch (Exception e) {
+            e.printStackTrace();
+            return null;
+        }
+    }
+}

src/main/java/com/fav/daengnyang/domain/chatbot/service/dto/request/CreateMessageRequest.java

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+package com.fav.daengnyang.domain.chatbot.service.dto.request;
+
+import jakarta.validation.constraints.NotNull;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import lombok.Setter;
+
+@Getter
+@Setter
+@NoArgsConstructor
+public class CreateMessageRequest {
+
+    @NotNull(message = "챗봇에게 보낼 메시지를 입력해 주세요.")
+    private String chat;
+}

src/main/java/com/fav/daengnyang/domain/chatbot/service/dto/response/MessageResponse.java

@@ -0,0 +1,18 @@
+package com.fav.daengnyang.domain.chatbot.service.dto.response;
+
+import lombok.Builder;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import lombok.Setter;
+
+@NoArgsConstructor
+@Getter
+@Setter
+public class MessageResponse {
+    private String chat;
+
+    @Builder
+    public MessageResponse(String chat) {
+        this.chat = chat;
+    }
+}