python-logging

• Metadata
  • Source: https://www.loggly.com/blog/exceptional-logging-of-exceptions-in-python/
  • Author: Aaron Maxwell
  • Tags: [[Python Learning]] [[programming]] [[logging]]
• Big Tarp Pattern

try: main() except Exception: logger.exception("Error in main()!")```

• logger.exception(msg) method will log a full stack trace of the error with the message
• This will log to the level ERROR
• Or, logging with logger.info(msg, exc_info=True) allows for a full stack trace and customization of the log level
• Pinpoint Pattern

try: object = some_function() except SomeSpecificError as err: logger.warn("Some specific error was raised. ".format(err.message))```

• You don’t need the full stack trace when you know which exception was raised
• Message and Raise Pattern

try: some_function() except SomeError: logger.warn("Error occured, not handling it.") raise```

• This pattern allows for a higher level handler to deal with it
• Cryptic Message (Anti-Pattern)

try: some_function() except SomeError: logger.warn("Something bad.")```

• This will cause confusion down the road because it doesn’t inform others where exactly this is occurring in the code
• FIX: add exec_info=True to give the full stack trace in the message
• All Shall Pass (Anti-Pattern)

try: some_function() except Exception: pass```

• This is the worst pattern of all because it hides the fact that there is an error
• Python logging levels
  • 1. CRITICAL
  • 2. ERROR
  • 3. WARNING
  • 4. INFO
  • 5. DEBUG