python config_error ai_generated true

LogCaptureWarning: No logger named 'myapp' found in caplog

ID: python/pytest-logging-capture-missing

Also available as: JSON · Markdown · 中文
80%Fix Rate
83%Confidence
0Evidence
2025-12-01First Seen

Version Compatibility

VersionStatusIntroducedDeprecatedNotes
7.0.0 active
8.0.0 active

Root Cause

The caplog fixture is used to capture log messages, but the specified logger name does not exist or has not been configured, so no log records are captured.

generic

中文

使用caplog fixture捕获日志消息,但指定的日志记录器名称不存在或未配置,因此未捕获到任何日志记录。

Workarounds

  1. 90% success Verify the logger name used in the code under test and match it in caplog
    In the test:
    import logging
    logger = logging.getLogger('myapp')
    logger.info('test message')
    with caplog.at_level(logging.INFO, logger='myapp'):
        # run code
        assert 'test message' in caplog.text
  2. 85% success Use caplog.set_level() to enable capturing for all loggers
    caplog.set_level(logging.DEBUG)
    # Now all log messages are captured
    assert 'expected message' in caplog.text

Dead Ends

Common approaches that don't work:

  1. Using caplog.clear() before capturing logs 50% fail

    This clears existing logs but does not fix the logger name issue.

  2. Setting the log level to DEBUG globally 40% fail

    This may generate more logs but does not ensure the correct logger is captured.