Integrate Spring With Open AI

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
	<modelVersion>4.0.0</modelVersion>
	<parent>
		<groupId>org.springframework.boot</groupId>
		<artifactId>spring-boot-starter-parent</artifactId>
		<version>3.3.2</version>
		<relativePath/> <!-- lookup parent from repository -->
	</parent>
	<groupId>br.com.erakles</groupId>
	<artifactId>spring-openai</artifactId>
	<version>0.0.1-SNAPSHOT</version>
	<name>spring-openai</name>
	<description>Demo project to explain the Spring and OpenAI integration</description>

	<properties>
		<java.version>17</java.version>
		<spring-ai.version>1.0.0-M1</spring-ai.version>
	</properties>

	<dependencies>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-web</artifactId>
		</dependency>

		<dependency>
			<groupId>org.apache.httpcomponents.client5</groupId>
			<artifactId>httpclient5</artifactId>
			<version>5.3.1</version>
		</dependency>

		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-test</artifactId>
			<scope>test</scope>
		</dependency>
	</dependencies>

	<build>
		<plugins>
			<plugin>
				<groupId>org.springframework.boot</groupId>
				<artifactId>spring-boot-maven-plugin</artifactId>
			</plugin>
		</plugins>
	</build>

</project>

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.MediaType;
import org.springframework.stereotype.Service;
import org.springframework.web.client.RestTemplate;

@Service
public class JavaOpenAIService {

    @Value("${openai.api.url}")
    private String apiUrl;

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

    @Value("${openai.api.model}")
    private String modelVersion;

    private final RestTemplate restTemplate;

    public JavaOpenAIService(RestTemplate restTemplate) {
        this.restTemplate = restTemplate;
    }

    /**
     * @param prompt - the question you are expecting to ask ChatGPT
     * @return the response in JSON format
     */
    public String ask(String prompt) {
        HttpEntity<String> entity = new HttpEntity<>(buildMessageBody(modelVersion, prompt), buildOpenAIHeaders());
        return restTemplate
                .exchange(apiUrl, HttpMethod.POST, entity, String.class)
                .getBody();
    }

    private HttpHeaders buildOpenAIHeaders() {
        HttpHeaders headers = new HttpHeaders();
        headers.set("Authorization", "Bearer " + apiKey);
        headers.set("Content-Type", MediaType.APPLICATION_JSON_VALUE);
        return headers;
    }

    private String buildMessageBody(String modelVersion, String prompt) {
        return String.format("{ \"model\": \"%s\", \"messages\": [{\"role\": \"user\", \"content\": \"%s\"}]}", modelVersion, prompt);
    }
}

import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

import br.com.erakles.springopenai.service.SpringOpenService;

@RestController
public class SpringOpenAIController {

    private final SpringOpenService springOpenService;

    SpringOpenAIController(SpringOpenService springOpenService) {
        this.springOpenService = springOpenService;
    }

    @GetMapping("/chat")
    public ResponseEntity<String> sendMessage(@RequestParam String prompt) {
        return ResponseEntity.ok(springOpenService.askMeAnything(prompt));
    }
}