[kvandre12-commits]

Summary

Fixes #294.

When KRX intermittently returns an empty response (e.g. under request load / rate limiting), dataframe_empty_handler already caught the resulting exception — most commonly ValueError: Length mismatch: Expected axis has 0 elements, new values have N elements, raised when the expected column names are assigned to an empty frame — and returned an empty DataFrame.

The problem is how it reported that: it used print() to stdout, so callers hitting KRX rate limits saw output that looks like a crash even though the call actually returned an (empty) result. It also called logging.info(args, kwargs), which misuses the logging API — the kwargs dict is passed as the %-format args, which would raise inside logging if INFO logging were enabled.

This aligns with the intent of #150, where empty responses were made to degrade gracefully instead of surfacing as errors.

Change

• Replace the print() + buggy logging.info(args, kwargs) with a single, suppressible logger.warning(...) on a module-level logger.
• Behaviour is otherwise unchanged: an empty DataFrame is still returned, and the same exception types are still handled.
• Callers can now silence or redirect it, e.g. logging.getLogger("pykrx").setLevel(logging.ERROR).

Before (simulated empty KRX response)

Error occurred in get_market_net_purchases_of_equities_by_ticker: Length mismatch: Expected axis has 0 elements, new values have 8 elements

Printed to stdout — indistinguishable from a real crash.

After

A single WARNING log record (suppressible via the standard logging config), and the same empty DataFrame return value.

Tests

• New offline unit tests in tests/test_dataframe_empty_handler.py:
  • empty response → empty DataFrame + a warning record (no exception, no stdout print),
  • passthrough of non-empty results,
  • KeyError / json.JSONDecodeError handling.
• Existing market integration tests replay cleanly:
  pytest tests/integration/test_market_api.py -k "net_purchase or equities or ohlcv_by_date" → 5 passed.
• ruff check and ruff format --check pass.

Notes

No public API or return-value changes — this only changes how the empty-response condition is reported (stdout print → warning log).

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요약 (KR)

KRX가 요청 부하/레이트리밋 등으로 일시적으로 빈 응답을 줄 때(#294), dataframe_empty_handler는 이미 예외(대개 빈 프레임에 컬럼명을 지정하며 발생하는 ValueError: Length mismatch)를 잡아 빈 DataFrame을 반환하고 있었습니다. 다만 그 사실을 print()로 stdout에 출력해 마치 크래시처럼 보였고, logging.info(args, kwargs) 호출은 logging API를 잘못 사용합니다. 이를 억제 가능한 logger.warning(...) 한 줄로 교체했습니다(반환값·동작 동일, 빈 DataFrame 반환). 이는 #150의 처리 방향과 일치합니다. 데코레이터에 대한 오프라인 단위 테스트를 추가했으며 기존 통합 테스트도 통과합니다.

[seohyunjun]

작성해주신 PR 감사합니다.
#291 Issue와 같은 문제로 사전에 먼저 제출한 이가 있어 #292 PR 승인했습니다. 혹시 더 추가하고 싶은 logger나 제안 있으면 변경된 코드로 작성해주시면 승인해드리겠습니다. 🙏