Python logging guide

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import logging
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# Configure immediately
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logging.basicConfig(
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    level=logging.INFO,
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    format='%(asctime)s - %(levelname)s - %(message)s',
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    filename='app.log' # Optional: Remove this line to print to console
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)
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logging.debug("This won't show (Level < INFO)")
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logging.info("Script processing started")
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logging.warning("Disk space low")
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logging.error("Database connection failed")

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import logging
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from .logging_config import setup_logging_dict
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from .make_connection import make_connection
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from .get_users import get_user
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logger = logging.getLogger(__name__)
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if __name__ == "__main__":
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    setup_logging_dict()
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    print(make_connection())
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    print(get_user(1))

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import logging
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import logging.config # separate import for `logging.config.dictConfig`
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from pathlib import Path
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import sys
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class ColorizedFormatter(logging.Formatter):
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    """a simple color fomatter for terminal"""
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    grey = "\x1b[38;20m"
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    purple = "\x1b[35;20m"
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    yellow = "\x1b[33;20m"
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    red = "\x1b[31;20m"
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    bold_red = "\x1b[31;1m"
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    reset = "\x1b[0m"
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    fmt = "%(asctime)s - %(name)s - %(levelname)s - %(message)s"
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    FORMATS = {
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        logging.DEBUG: purple + fmt + reset,
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        logging.INFO: grey + fmt + reset,
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        logging.WARNING: yellow + fmt + reset,
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        logging.ERROR: red + fmt + reset,
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        logging.CRITICAL: bold_red + fmt + reset,
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    }
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    def format(self, record):
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        log_fmt = self.FORMATS.get(record.levelno)
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        formatter = logging.Formatter(log_fmt)
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        return formatter.format(record)
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def setup_logging_dict():
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    """the actual setup for the logger"""
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    log_path = Path("learn_logging") / "app.log"
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    log_path.parent.mkdir(parents=True, exist_ok=True)
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    # 1. version is required and cannot be a float
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    # 2. disable_existing_loggers is also required and othewise it would slient
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    # 3. it basically has 3 component: the formatter, handler, and logger itself (for different module/package)
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    config = {
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        "version": 1,
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        "disable_existing_loggers": False,
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        "formatters": {
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            "standard": {"format": "%(asctime)s - %(module)s - %(levelname)s - %(message)s"},
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            "console_format": {"()": ColorizedFormatter},
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        },
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        "handlers": {
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            "file": {
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                "class": "logging.FileHandler",
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                "level": "DEBUG",
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                "formatter": "standard",
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                "filename": str(log_path),
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                "mode": "w",
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            },
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            "console": {
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                "class": "logging.StreamHandler",
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                "level": "DEBUG",
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                "formatter": "console_format",
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                "stream": sys.stdout,
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            },
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        },
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        "root": {
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            "handlers": ["console", "file"],
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            "level": "DEBUG",
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        },
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        "loggers": {
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            "my_cool_module": {
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                "level": "DEBUG",
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                "propagate": True,
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            },
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            "urllib3": {
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                "level": "WARNING",
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                "propagate": True,
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            },
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        },
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    }
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    logging.config.dictConfig(config=config)