nanolog

nanolog

Life is too short. Use nanolog to make logging and printing simpler!

nanolog features a convenient logger API built on top of python's builtin logging.

The library also ships with many printing utilities. Python 3 only.

Installation

From stable package on PyPI

.. code:: bash

pip install nanolog

From bleeding edge master branch

.. code:: bash

pip install git+git://github.com/SurrealAI/nanolog.git

nanolog.Logger

Logging levels, from least severe to most:

• LOG_ALL: log everything
• TRACE: fine-grained debugging messages
• DEBUG: normal debugging
• INFO: messages you usually don't want to see
• NOTICE (i.e. INFO5): non-error messages you usually want to see
• WARNING: exceptional circumstances that might not be errors
• ERROR: errors that occur, but are anticipated and handled
• CRITICAL: fatal errors that lead to termination
• LOG_OFF: turn off all logging

.. code:: python

import nanolog as nl

logger = nl.Logger.create_logger(
    'main',
    stream='out',
    level='debug',
)

logger.info('my', 3, 'world', 1/16.)  # just like print
# >>> my 3 world 0.0625

# nanolog use 'warn' instead of 'warning'
logger.warnfmt('{}, we are {:.3f} miles from {planet}',
               'Houston', 17/7, planet='Mars')  # just like str.format
# >>> Houston, we are 2.429 miles from Mars

Use a trailing number to indicate level, the larger the higher priority

.. code:: python

logger.info7(...)  # info level 7
logger.errorfmt8(...)  # error level 8

Display a banner line or block

.. code:: python

logger.infobanner3('my', 3, 'world', symbol='!', banner_len=16, banner_lines=3)

prints:

::

!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!! my 3 world !!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Of course, banner method also comes with a str.format version

.. code:: python

logger.debugbannerfmt(
    '{3}&{0}&{2}&{1}', 'a', 'b', 'c', 'd', 
    symbol='<*_*>', banner_len=16, banner_lines=6
)

displays:

::

<*_*><*_*><*_*><*_*><*_*>
<*_*><*_*><*_*><*_*><*_*>
<*_*><*_ d&a&c&b <*_*><*_
<*_*><*_*><*_*><*_*><*_*>
<*_*><*_*><*_*><*_*><*_*>
<*_*><*_*><*_*><*_*><*_*>

Prettyprint support (uses the thirdparty lib prettyprinter)

.. code:: python

logger.infopp7(...)
logger.warnppfmt('my warning {:.3f} format {:.2f} string', 1/7., 1/9.)

Logger config

TODO

Time formatting

TODO

Printing utililites

prettyprint

Better alternatives for the pprint module in python standard lib.

• pprint: takes variable number of objects, just like print()

• pprintstr: return string instead of printing to IO stream

• pprintfmt: just like print('...'.format)

• pprintfmtstr: return string instead of printing to IO stream

Convenient aliases (pp stands for prettyprint; a single p means normal print)

+--------------+--------------------+ | short | original | +==============+====================+ | pf | printfmt | +--------------+--------------------+ | pferr | printfmterr | +--------------+--------------------+ | pstr | printstr | +--------------+--------------------+ | perr | printerr | +--------------+--------------------+ | pp | pprint | +--------------+--------------------+ | ppstr | pprintstr | +--------------+--------------------+ | ppf | pprintfmt | +--------------+--------------------+ | ppfstr | pprintfmtstr | +--------------+--------------------+

TODO: talk about global configs

Print redirection context managers

• PrintRedirection
• PrintFile
• PrintSuppress
• PrintString