Synnefo » ./kamaki

# Copyright 2013 GRNET S.A. All rights reserved.

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# Redistribution and use in source and binary forms, with or

# without modification, are permitted provided that the following

# conditions are met:

#

#   1. Redistributions of source code must retain the above

#      copyright notice, this list of conditions and the following

#      disclaimer.

#

#   2. Redistributions in binary form must reproduce the above

#      copyright notice, this list of conditions and the following

#      disclaimer in the documentation and/or other materials

#      provided with the distribution.

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# THIS SOFTWARE IS PROVIDED BY GRNET S.A. ``AS IS'' AND ANY EXPRESS

# OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED

# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR

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from os import chmod

from os.path import expanduser

import logging

LOG_FILE = [expanduser('~/.kamaki.log')]

ALL = 0

_blacklist = {}

def deactivate(name):

    """Deactivate a logger. Can be restored"""

    xlogger = logging.getLogger(name)

    _blacklist[name] = xlogger.level

    xlogger.setLevel(logging.CRITICAL)

def activate(name):

    """Restore a loggers settings"""

    old_logger = logging.getLogger(name)

    old_logger.setLevel(_blacklist.pop(name, old_logger.level))

def if_logger_enabled(func):

    def wrap(name, *args, **kwargs):

        if name in _blacklist:

            return logging.getLogger(name)

        return func(name, *args, **kwargs)

    return wrap

def get_log_filename():

    for logfile in LOG_FILE:

        try:

            with open(logfile, 'a+') as f:

                f.seek(0)

            chmod(logfile, 0600)

        except IOError:

            continue

        return logfile

    print('Failed to open any logging locations, file-logging aborted')

def set_log_filename(filename):

    global LOG_FILE

    LOG_FILE[0] = filename

def _add_logger(name, level=None, filename=None, fmt=None):

    log = get_logger(name)

    h = logging.FileHandler(filename) if (

        filename) else logging.StreamHandler()

    lfmt = logging.Formatter(fmt or '%(name)s\n %(message)s')

    h.setFormatter(lfmt)

    log.addHandler(h)

    log.setLevel(level or logging.DEBUG)

    return log

@if_logger_enabled

def add_file_logger(name, level=None, filename=None):

    try:

        return _add_logger(

            name, level, filename or get_log_filename(),

            fmt='%(name)s(%(levelname)s) %(asctime)s\n\t%(message)s')

    except Exception:

        return get_logger(name)

@if_logger_enabled

def add_stream_logger(name, level=None, fmt=None):

    try:

        return _add_logger(name, level, fmt=fmt)

    except Exception:

        return get_logger(name)

@if_logger_enabled

def get_logger(name):

    return logging.getLogger(name)