Source code for gemseo.utils.logging_tools

# Copyright 2021 IRT Saint Exupéry, https://www.irt-saintexupery.com
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
# License version 3 as published by the Free Software Foundation.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
# Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public License
# along with this program; if not, write to the Free Software Foundation,
# Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
# Contributors:
#    INITIAL AUTHORS - initial API and implementation and/or initial
#                           documentation
#        :author: Antoine Dechaume
#    OTHER AUTHORS   - MACROSCOPIC CHANGES
"""
Logging tools
=============
"""
from __future__ import annotations

import logging
import types


[docs]class MultiLineHandlerMixin: """Stateless mixin class to override logging handlers behavior.""" @staticmethod def __get_raw_record_message(record): """Return the raw message of a log record.""" return record.msg
[docs] def emit(self, record): """Emit one logging message per input record line.""" # compute the message without the logging prefixes (timestamp, level, ...) message = record.getMessage() # replace getMessage so the message is not computed again when emitting # each line record.getMessage = types.MethodType(self.__get_raw_record_message, record) # backup old raw message old_msg = record.msg for line in message.split("\n"): record.msg = line super().emit(record) # restore genuine getMessage and raw message for other handlers record.getMessage = types.MethodType(logging.LogRecord.getMessage, record) record.msg = old_msg
[docs]class MultiLineStreamHandler(MultiLineHandlerMixin, logging.StreamHandler): """StreamHandler to split multiline logging messages."""
[docs]class MultiLineFileHandler(MultiLineHandlerMixin, logging.FileHandler): """FileHandler to split multiline logging messages."""
[docs]class LoggingContext: """Context manager for selective logging. Change the level of the logger in a ``with`` block. Examples: logger.setLevel(logging.INFO) logger.info("This should appear.") with LoggingContext(logger, logging.WARNING): logger.warning("This should appear.") logger.info("This should not appear.") logger.info("This should appear.") Source: `Logging Cookbook <https://docs.python.org/3/howto/ logging-cookbook.html#using-a-context-manager-for-selective-logging>`_ """ def __init__(self, logger, level, handler=None, close=True): """ Args: logger: The logger. level: The level of the logger to be used on block entry. handler: An additional handler to be used on block entry. close: Whether to close the handler on block exit. """ self.logger = logger self.level = level self.handler = handler self.close = close def __enter__(self): if self.level is not None: self.old_level = self.logger.level self.logger.setLevel(self.level) if self.handler: self.logger.addHandler(self.handler) def __exit__(self, et, ev, tb): if self.level is not None: self.logger.setLevel(self.old_level) if self.handler: self.logger.removeHandler(self.handler) if self.handler and self.close: self.handler.close()
# implicit return of None => don't swallow exceptions