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API Reference

Build a simple logger

logging_std.build_logger(*, verbose=False, error_stream=None, info_stream=None) cached

Build a logger that outputs to the standard output and error streams.

Messages of level INFO go to the standard output stream. Messages of level WARNING and higher go to the standard error stream. If verbose is true, messages of level DEBUG also go to the standard error stream.

The stream to send error messages to may be overridden by the error_stream parameter, and the one for informational messages - by the info_stream one.

Source code in src/logging_std/__init__.py 
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@functools.lru_cache
def build_logger(
    *,
    verbose: bool = False,
    error_stream: TextIO | None = None,
    info_stream: TextIO | None = None,
) -> logging.Logger:
    """Build a logger that outputs to the standard output and error streams.

    Messages of level `INFO` go to the standard output stream.
    Messages of level `WARNING` and higher go to the standard error stream.
    If `verbose` is true, messages of level `DEBUG` also go to the standard error stream.

    The stream to send error messages to may be overridden by the `error_stream` parameter,
    and the one for informational messages - by the `info_stream` one.
    """
    logger: Final = logging.getLogger("logging_std")
    logger.setLevel(logging.DEBUG if verbose else logging.INFO)
    logger.propagate = False

    if error_stream is None:
        error_stream = sys.stderr
    diag_handler: Final = logging.StreamHandler(error_stream)
    diag_handler.setLevel(logging.DEBUG if verbose else logging.WARNING)
    diag_handler.addFilter(lambda rec: rec.levelno != logging.INFO)
    logger.addHandler(diag_handler)

    if info_stream is None:
        info_stream = sys.stdout
    info_handler: Final = logging.StreamHandler(info_stream)
    info_handler.setLevel(logging.INFO)
    info_handler.addFilter(lambda rec: rec.levelno == logging.INFO)
    logger.addHandler(info_handler)

    return logger

logging_std.build_single_logger(*, verbose=False, stream=None) cached

Build a logger that outputs to the standard error stream.

Messages of level INFO and higher go to the standard error stream. If verbose is true, messages of level DEBUG also go to the standard error stream.

The stream to send messages to may be overridden by the stream parameter.

Source code in src/logging_std/__init__.py 
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@functools.lru_cache
def build_single_logger(
    *,
    verbose: bool = False,
    stream: TextIO | None = None,
) -> logging.Logger:
    """Build a logger that outputs to the standard error stream.

    Messages of level `INFO` and higher go to the standard error stream.
    If `verbose` is true, messages of level `DEBUG` also go to the standard error stream.

    The stream to send messages to may be overridden by the `stream` parameter.
    """
    logger: Final = logging.getLogger("logging_std")
    logger.setLevel(logging.DEBUG if verbose else logging.INFO)
    logger.propagate = False

    if stream is None:
        stream = sys.stderr
    diag_handler: Final = logging.StreamHandler(stream)
    diag_handler.setLevel(logging.DEBUG if verbose else logging.INFO)
    logger.addHandler(diag_handler)

    return logger