logger.py

# Copyright 2013 GRNET S.A. All rights reserved.
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from os import chmod
import logging


LOG_FILE = ['kamaki.log', '/tmp/kamaki.log']


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 = [filename] + LOG_FILE


def add_file_logger(
        name, caller,
        level=logging.DEBUG, prefix='', filename='/tmp/kamaki.log'):
    try:
        assert caller and filename
        logger = logging.getLogger(name)
        h = logging.FileHandler(filename)
        fmt = logging.Formatter(
            '%(asctime)s ' + caller + ' %(name)s-%(levelname)s: %(message)s')
        h.setFormatter(fmt)
        logger.addHandler(h)
        logger.setLevel(level)
    except Exception:
        pass


def get_logger(name):
    return logging.getLogger(name)