qa/qa_logging.py

#
#

# Copyright (C) 2014 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.

""" Handles the logging of messages with appropriate coloring.

"""

import sys


_INFO_SEQ = None
_WARNING_SEQ = None
_ERROR_SEQ = None
_RESET_SEQ = None


def _SetupColours():
  """Initializes the colour constants.

  """
  # pylint: disable=W0603
  # due to global usage
  global _INFO_SEQ, _WARNING_SEQ, _ERROR_SEQ, _RESET_SEQ

  # Don't use colours if stdout isn't a terminal
  if not sys.stdout.isatty():
    return

  try:
    import curses
  except ImportError:
    # Don't use colours if curses module can't be imported
    return

  curses.setupterm()

  _RESET_SEQ = curses.tigetstr("op")

  setaf = curses.tigetstr("setaf")
  _INFO_SEQ = curses.tparm(setaf, curses.COLOR_GREEN)
  _WARNING_SEQ = curses.tparm(setaf, curses.COLOR_YELLOW)
  _ERROR_SEQ = curses.tparm(setaf, curses.COLOR_RED)


_SetupColours()


def _FormatWithColor(text, seq):
  if not seq:
    return text
  return "%s%s%s" % (seq, text, _RESET_SEQ)


FormatWarning = lambda text: _FormatWithColor(text, _WARNING_SEQ)
FormatError = lambda text: _FormatWithColor(text, _ERROR_SEQ)
FormatInfo = lambda text: _FormatWithColor(text, _INFO_SEQ)