🪵 Logging

Logging records what happened and when so you can debug failures and understand system behavior. Unlike print, logs are structured, configurable, and can be stored in files or external systems.

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✅ Why Logging Matters

• Debugging: See context around failures.
• Monitoring: Track errors in production.
• Auditing: Keep a record of important events.

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✅ Basic Logging Example

import logging

logging.basicConfig(level=logging.INFO)

logging.info("App started")
logging.warning("Low disk space")
logging.error("Failed to connect to database")

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✅ Logging Levels

Level	Use Case
DEBUG	Detailed diagnostic info
INFO	Normal events
WARNING	Unexpected, but not fatal
ERROR	Something failed
CRITICAL	App cannot continue

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✅ Logging Exceptions

try:
    risky_operation()
except Exception:
    logging.exception("Something went wrong")

logging.exception records the traceback automatically.

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🔍 Key Takeaways

• Use logging instead of print for real applications.
• Choose the right log level for each message.
• Log exceptions with tracebacks for faster debugging.

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