[FEAT] 헤드라인 생성을 위한 GPT API 설정

Author: EunbeenDev

src/main/java/com/movelog/domain/gpt/application/GptService.java

@@ -0,0 +1,63 @@
+package com.movelog.domain.gpt.application;
+
+import com.fasterxml.jackson.databind.JsonNode;
+import lombok.RequiredArgsConstructor;
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.http.MediaType;
+import org.springframework.stereotype.Service;
+import org.springframework.web.reactive.function.client.WebClient;
+import reactor.core.publisher.Mono;
+
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+@Service
+@RequiredArgsConstructor
+@Slf4j
+public class GptService {
+
+    private final WebClient gptWebClient;  // @Qualifier 제거하고 빈 이름에 맞는 생성자 주입
+    @Value("${chatgpt.api-key}")
+    private String apiKey;
+    @Value("${chatgpt.model}")
+    private String model;
+    @Value("${chatgpt.max-tokens}")
+    private Integer maxTokens;
+    @Value("${chatgpt.temperature}")
+    private Double temperature;
+    @Value("${chatgpt.top-p}")
+    private Double topP;
+
+    public Mono<JsonNode> callChatGpt(String prompt) {
+        return gptWebClient.post()
+                .uri("/chat/completions")  // 경로에 대한 수정
+                .header("Authorization", "Bearer " + apiKey)
+                .contentType(MediaType.APPLICATION_JSON)
+                .bodyValue(buildRequestBody(prompt))
+                .retrieve()
+                .bodyToMono(JsonNode.class)
+                .doOnSuccess(response -> log.info("GPT API 응답 성공: {}", response))
+                .doOnError(error -> log.error("GPT API 호출 중 오류 발생: {}", error.getMessage()))
+                .onErrorResume(error -> {
+                    log.error("GPT API 호출 중 예외 처리 발생: {}", error.getMessage());
+                    return Mono.error(new RuntimeException("GPT API 호출 실패", error));
+                });
+    }
+
+    private Map<String, Object> buildRequestBody(String prompt) {
+        Map<String, Object> bodyMap = new HashMap<>();
+        bodyMap.put("model", model);
+        bodyMap.put("max_tokens", maxTokens);
+        bodyMap.put("temperature", temperature);
+        bodyMap.put("top_p", topP);
+        bodyMap.put("messages", List.of(
+                Map.of(
+                        "role", "user",
+                        "content", prompt
+                )
+        ));
+        return bodyMap;
+    }
+}