[OpenAI] 스프링을 활용해 API 요청 보내기

dependencies {
    implementation 'org.springframework.boot:spring-boot-starter-web'
    compileOnly 'org.projectlombok:lombok'
    developmentOnly 'org.springframework.boot:spring-boot-devtools'
    annotationProcessor 'org.springframework.boot:spring-boot-configuration-processor'
    annotationProcessor 'org.projectlombok:lombok'
    testImplementation 'org.springframework.boot:spring-boot-starter-test'
    testRuntimeOnly 'org.junit.platform:junit-platform-launcher'

    implementation 'com.fasterxml.jackson.core:jackson-databind:2.15.0'
    implementation 'org.apache.httpcomponents.client5:httpclient5:5.1'
    implementation 'org.springframework.boot:spring-boot-starter-json'

}

openai:
  api:
    key: YOUR_OPENAI_API_KEY

package org.example.openaitest._core;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.filter.CharacterEncodingFilter;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;

@Configuration
public class WebConfig implements WebMvcConfigurer {

    @Bean
    public CharacterEncodingFilter characterEncodingFilter() {
        CharacterEncodingFilter filter = new CharacterEncodingFilter();
        filter.setEncoding("UTF-8");
        filter.setForceEncoding(true);
        return filter;
    }
}

package org.example.openaitest.ai;

import lombok.RequiredArgsConstructor;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.ResponseBody;

import java.io.IOException;

@RequiredArgsConstructor
@Controller
public class OpenAIController {

    private final OpenAIService openAIService;


    @GetMapping("/")
    public String index() {
        return "index"; 
    }

    @PostMapping("/api/openai/generate-poem")
    @ResponseBody
    public String generatePoem(@RequestBody OpenAIRequest.RequestDTO request) throws IOException {
        return openAIService.getResponse(request.getContent());
    }
}

package org.example.openaitest.ai;

import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.ObjectMapper;
import org.apache.hc.client5.http.classic.methods.HttpPost;
import org.apache.hc.client5.http.impl.classic.CloseableHttpClient;
import org.apache.hc.client5.http.impl.classic.CloseableHttpResponse;
import org.apache.hc.client5.http.impl.classic.HttpClients;
import org.apache.hc.core5.http.io.entity.StringEntity;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Service;

import java.io.IOException;
import java.nio.charset.StandardCharsets;

@Service
public class OpenAIService {

    @Value("${openai.api.key}")
    private String apiKey;

    private final ObjectMapper objectMapper;

    public OpenAIService(ObjectMapper objectMapper) {
        this.objectMapper = objectMapper;
    }

    public String getResponse(String prompt) throws IOException {
        try (CloseableHttpClient httpClient = HttpClients.createDefault()) {
            HttpPost request = new HttpPost("https://api.openai.com/v1/chat/completions");
            request.setHeader("Content-Type", "application/json; charset=UTF-8");
            request.setHeader("Authorization", "Bearer " + apiKey);

            String json = "{ \"model\": \"gpt-3.5-turbo\", \"messages\": [" +
                    "{\"role\": \"system\", \"content\": \"당신은 음악 스트리밍 관리자입니다. 모든 응답을 한국어로 해주세요.\"}," +
                    "{\"role\": \"user\", \"content\": \"" + prompt + "\"}] }";
            request.setEntity(new StringEntity(json, StandardCharsets.UTF_8));

            try (CloseableHttpResponse response = httpClient.execute(request)) {
                JsonNode jsonNode = objectMapper.readTree(response.getEntity().getContent());
                return jsonNode.get("choices").get(0).get("message").get("content").asText();
            }
        }
    }
}

package org.example.openaitest.ai;


import lombok.Data;

public class OpenAIRequest {

    @Data
    public static class RequestDTO{
        private String content;
    }

}

<!DOCTYPE html>
<html lang="ko">
<head>
    <meta charset="UTF-8">
    <title>OpenAI API 테스트</title>
    <script src="https://code.jquery.com/jquery-3.6.0.min.js"></script>
</head>
<body>
<h1>OpenAI API 사용</h1>
<form id="prompt-form">
    <label for="prompt">프롬프트 입력:</label><br>
    <textarea id="prompt" name="prompt" rows="4" cols="50"></textarea><br><br>
    <input type="button" value="제출" onclick="submitPrompt()">
</form>
<h2>응답:</h2>
<pre id="response"></pre>

<script>
    function submitPrompt() {
        var prompt = $('#prompt').val();
        $.ajax({
            url: '/api/openai/generate-poem',
            type: 'POST',
            contentType: 'application/json',
            data: JSON.stringify({ prompt: prompt }),
            success: function(response) {
                $('#response').text(response);
            },
            error: function(error) {
                $('#response').text('Error: ' + error.responseText);
            }
        });
    }
</script>
</body>
</html>