adam/logging_setup.py

from __future__ import annotations

import logging
from logging.handlers import RotatingFileHandler
from pathlib import Path


def configure_logging(root: Path) -> logging.Logger:
    log_dir = root / "logs"
    log_dir.mkdir(parents=True, exist_ok=True)

    logger = logging.getLogger("adam")
    logger.setLevel(logging.INFO)
    desired_log = str((log_dir / "adam.log").resolve())
    existing_file = next(
        (
            handler
            for handler in logger.handlers
            if isinstance(handler, RotatingFileHandler)
            and str(Path(handler.baseFilename).resolve()) == desired_log
        ),
        None,
    )
    if existing_file is not None:
        return logger
    for handler in list(logger.handlers):
        logger.removeHandler(handler)
        handler.close()

    formatter = logging.Formatter(
        "%(asctime)s | %(levelname)-7s | %(name)s | %(message)s",
        datefmt="%Y-%m-%d %H:%M:%S",
    )
    file_handler = RotatingFileHandler(
        log_dir / "adam.log",
        maxBytes=2_000_000,
        backupCount=3,
        encoding="utf-8",
    )
    file_handler.setFormatter(formatter)
    logger.addHandler(file_handler)

    console_handler = logging.StreamHandler()
    console_handler.setFormatter(formatter)
    logger.addHandler(console_handler)
    return logger