Source code for pi3d.util.Log

from __future__ import absolute_import, division, print_function, unicode_literals

import errno
import logging
import os
import os.path

[docs]class Log(object): def __init__(self, name=None, level='WARNING', file=None, format=None): ''' The typical usage of the Log module has a single LOGGER per Python file. At the top of the file is typically: LOGGER = pi3d.Log(level='INFO', file='error.log') and then later on you can do things like: * LOGGER.debug('stuff here') *'Some information about %s', some_name) * LOGGER.error('Not everything was displayed, sorry!') * LOGGER.error('You died with error code %d, message %s', error_code, msg) * LOGGER.critical('Your machine is about to explode. Leave the building.') (Note that the values for the format string, like "some_name", "error_code" or "msg" are passed in as arguments - that's so you never even construct the message if it isn't going to be displayed.) ***N.B. if name is not passed as an argument then this will set the root logger properties (and all the pi3d module logging will also be logged, which is what you usually want.)*** The level, file, format arguments are passed on to set_logs() see below. ''' self.logger = logging.getLogger(name) # NB overriding default None will stop module logging! self.debug = self.logger.debug # to reference methods to those of the logger instance = self.warning = self.logger.warning self.error = self.logger.error self.critical = self.logger.critical # pi3d only adds one handler for each instance of Log. self.HANDLER holds a # reference to it so that can be changed by subsequent calls to set_logs() self.HANDLER = None self.set_logs(level, file, format)
[docs] def set_logs(self, level=None, file=None, format=None): ''' You can redirect, filter or reformat your logging by calling Log.set_logs(). Log.set_logs() has three optional parameters: level: can be one of 'DEBUG', 'INFO', 'WARNING', 'ERROR', or 'CRITICAL'. Everything that's the current log level or greater is displayed - for example, if your current log level is 'WARNING', then you'll display all warning, error, or critical messages. If this argument is not supplied then the level will not change from previously set. file: is the name of a file to which to redirect messages. If this argument is not supplied or is set to None then logging to file will stop if previously set, and will be directed to terminal. format: controls what information is in the output messages. The default is `'%(asctime)s %(levelname)s: %(name)s: %(message)s'` which results in output looking like this: `time LEVEL: filename: Your Message Here.`''' if level is not None: self.logger.setLevel(level.upper()) hdlrs = self.logger.handlers # shortcut if self.HANDLER is not None: # this is one created by pi3d previously if self.HANDLER not in hdlrs: # error if it's been deleted by external actions self.HANDLER = None # shouldn't really get here but see above if file: # make new FileHandler file_handler = logging.FileHandler(file) if self.HANDLER is not None: self.logger.removeHandler(self.HANDLER) self.logger.addHandler(file_handler) self.HANDLER = file_handler else: # check if FileHandler previously and remove so logging to screen if type(self.HANDLER) == logging.FileHandler: self.logger.removeHandler(self.HANDLER) self.HANDLER = None if self.HANDLER is None: # need to make a new StreamHandler self.HANDLER = logging.StreamHandler() self.logger.addHandler(self.HANDLER) if format is None: format = '%(asctime)s %(levelname)s: %(name)s: %(message)s' self.HANDLER.setFormatter(logging.Formatter(format))