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#

#

# Copyright (C) 2006, 2007 Google Inc.

#

# This program is free software; you can redistribute it and/or modify

# it under the terms of the GNU General Public License as published by

# the Free Software Foundation; either version 2 of the License, or

# (at your option) any later version.

#

# 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

# General Public License for more details.

#

# You should have received a copy of the GNU 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.

"""Logging for Ganeti

This module abstracts the logging handling away from the rest of the

Ganeti code. It offers some utility functions for easy logging.

"""

# pylint: disable-msg=W0603,C0103

import sys

import logging

def SetupLogging(logfile, debug=False, stderr_logging=False, program=""):

  """Configures the logging module.

  """

  fmt = "%(asctime)s: " + program + " "

  if debug:

    fmt += ("pid=%(process)d/%(threadName)s %(levelname)s"

           " %(module)s:%(lineno)s %(message)s")

  else:

    fmt += "pid=%(process)d %(levelname)s %(message)s"

  formatter = logging.Formatter(fmt)

  root_logger = logging.getLogger("")

  root_logger.setLevel(logging.NOTSET)

  if stderr_logging:

    stderr_handler = logging.StreamHandler()

    stderr_handler.setFormatter(formatter)

    if debug:

      stderr_handler.setLevel(logging.NOTSET)

    else:

      stderr_handler.setLevel(logging.CRITICAL)

    root_logger.addHandler(stderr_handler)

  # this can fail, if the logging directories are not setup or we have

  # a permisssion problem; in this case, it's best to log but ignore

  # the error if stderr_logging is True, and if false we re-raise the

  # exception since otherwise we could run but without any logs at all

  try:

    logfile_handler = logging.FileHandler(logfile)

    logfile_handler.setFormatter(formatter)

    if debug:

      logfile_handler.setLevel(logging.DEBUG)

    else:

      logfile_handler.setLevel(logging.INFO)

    root_logger.addHandler(logfile_handler)

  except EnvironmentError, err:

    if stderr_logging:

      logging.exception("Failed to enable logging to file '%s'", logfile)

    else:

      # we need to re-raise the exception

      raise

# Backwards compatibility

Error = logging.error

Info = logging.info

Debug = logging.debug

def ToStdout(txt):

  """Write a message to stdout only, bypassing the logging system

  Parameters:

    - txt: the message

  """

  sys.stdout.write(txt + '\n')

  sys.stdout.flush()

def ToStderr(txt):

  """Write a message to stderr only, bypassing the logging system

  Parameters:

    - txt: the message

  """

  sys.stderr.write(txt + '\n')

  sys.stderr.flush()