Logging System

Python's logging module provides a flexible framework for emitting log messages from Python programs.

📦 Components

• logging.Logger - Main logger interface for applications
• logging.Handler - Base class for all logging handlers
• logging.Formatter - Format log records for output
• logging.Filter - Filter log records based on criteria
• logging.config - Configuration utilities for logging

🔍 Quick Reference

Component	Purpose	Key Methods
Logger	Emit log messages	debug(), info(), warning(), error(), critical()
Handler	Route log records	emit(), handle(), setLevel()
Formatter	Format log output	format(), formatTime()
Filter	Filter log records	filter()

🚀 Basic Usage

import logging

# Configure basic logging
logging.basicConfig(level=logging.INFO)

# Get a logger
logger = logging.getLogger(__name__)

# Log messages
logger.debug("Debug message")
logger.info("Info message")
logger.warning("Warning message")
logger.error("Error message")
logger.critical("Critical message")

📊 Log Levels

Level	Numeric Value	When to Use
CRITICAL	50	Serious errors, program may abort
ERROR	40	Serious problems, but program continues
WARNING	30	Something unexpected happened
INFO	20	Confirmation that things work as expected
DEBUG	10	Detailed information for diagnosing problems