Feat/apply async

[Bumnote]

#️⃣ 연관된 이슈

#52

📝 작업 내용

• 기존 동기 방식 -> Async + CompletableFuture 비동기 방식으로 전환
• 가상 사용자 30명 기준 1초 동안 동시 요청을 했을 때, 전후 비교는 다음과 같습니다.

개선 전

개선 후

결론

• 개선 후, 실패률이 더 높았을 뿐 아니라, Heap 사용량 또한 대폭 증가한 것을 확인할 수 있었습니다.

💬 리뷰 요구사항

리뷰어가 특별히 봐주었으면 하는 부분이 있다면 작성해주세요

[Copilot]

Pull Request Overview

This PR converts the travel analysis service from synchronous to asynchronous processing using @Async and CompletableFuture. The goal was to improve performance under concurrent load, though the PR description notes that the change actually resulted in higher failure rates and increased heap usage.

• Introduced async processing with custom thread pool configuration
• Refactored service layer to return CompletableFuture types
• Added new persistence service to separate concerns

Reviewed Changes

Copilot reviewed 9 out of 10 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
application.yml	Increased max-request-size and updated OpenAI model version
CustomRejectedExecutionHandler.java	New custom handler for thread pool saturation with caller-runs fallback
AsyncConfig.java	Thread pool configuration for OpenAI operations
RetripService.java	Converted to async processing, removed business logic moved to persistence service
RetripPersistenceService.java	New service handling database operations and entity building
OpenAiClient.java	Added async annotation and CompletableFuture return type
GptImageAnalysisService.java	Updated to work with async CompletableFuture pattern
RetripController.java	Modified to handle async responses
README.md	Updated project documentation

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[Copilot]

Running rejected tasks synchronously on the caller thread defeats the purpose of async processing and can cause thread blocking. Consider implementing a proper backpressure mechanism or circuit breaker pattern instead.

Suggested change

	try {
	log.info("호출 스레드에서 작업 실행 재시도");
	r.run();
	} catch (Exception e) {
	log.error("거부된 작업 재실행 중 오류 발생", e);
	}
	log.error("거부된 작업이 드롭되었습니다. (Rejected task dropped)");

[Copilot]

Throwing an exception inside exceptionally() creates an unhandled exception that will be wrapped in a CompletionException. This should return a default value or use handle() method instead to properly manage the exception flow.

Suggested change

	.exceptionally(throwable -> {
	log.error("전체 처리 과정에서 오류 발생", throwable);
	throw new RuntimeException("여행 분석 처리 중 오류가 발생했습니다: " + throwable.getMessage(), throwable);
	.handle((result, throwable) -> {
	if (throwable != null) {
	log.error("전체 처리 과정에서 오류 발생", throwable);
	throw new RuntimeException("여행 분석 처리 중 오류가 발생했습니다: " + throwable.getMessage(), throwable);
	}
	return result;

[Copilot]

Wrapping the original exception in a RuntimeException loses the specific exception type information. Consider returning the original exception using CompletableFuture.failedFuture(e) or creating a more specific custom exception type.

Suggested change

	return CompletableFuture.failedFuture(
	new RuntimeException("GPT API 호출 중 오류가 발생했습니다: " + e.getMessage(), e)
	);
	return CompletableFuture.failedFuture(e);