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📜 Sublog

Sublog is a nuclear's contextual logging system that allows you to:

  • display variables besides log messages: logger.debug('message', airspeed=20),
  • wrap errors with context: with add_context('ignition'),
  • catch errors and show traceback in a concise, pretty format: with error_handler().
from nuclear.sublog import logger, error_handler, add_context

with error_handler():
    logger.debug('checking engine', temperature=85.0, pressure='12kPa')
    with add_context('ignition', request=42):
        logger.info('ignition ready', speed='zero')
        with add_context('liftoff'):
            raise RuntimeError('explosion')

sublog demo

Context logger

Use nuclear.sublog.logger to log message with a pretty format out of the box.

Pass additional context variables as keyword arguments to display them in the log message.

from nuclear.sublog import logger

logger.info('info log')
logger.debug('debug log', var1=1, var2='two')
logger.info('not great not terrible', radioactivity=3.6)
logger.error('this is bad')
logger.exception(RuntimeError('this is worse'))

Error handler

Use nuclear.sublog.error_handler to catch errors and show traceback in a concise, pretty format.

from nuclear.sublog import error_handler

with error_handler():
    raise RuntimeError('explosion')

Wrapping context

Use nuclear.sublog.add_context to wrap code with additional context information. This will be included in in the log message, if an error occurs.

from nuclear.sublog import add_context

with add_context('reloading plugins'):
    with add_context('loading config'):
        raise RuntimeError('file is missing')
This will produce an error with the following message: 
reloading plugins: loading config: file is missing

Note that while each individual part of the message may not provide a comprehensive explanation of the error, when combined, the whole message becomes highly informative. This is the core principle behind enriching errors with context.