1 # Copyright 2009 the Melange authors.

     2 #

     3 # Licensed under the Apache License, Version 2.0 (the "License");

     4 # you may not use this file except in compliance with the License.

     5 # You may obtain a copy of the License at

     6 #

     7 #   http://www.apache.org/licenses/LICENSE-2.0

     8 #

     9 # Unless required by applicable law or agreed to in writing, software

    10 # distributed under the License is distributed on an "AS IS" BASIS,

    11 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

    12 # See the License for the specific language governing permissions and

    13 # limitations under the License.

    14 

    15 """Various utilities.

    16 

    17 Current contents:

    18  - Text colorization using ANSI color codes

    19 """

    20 

    21 __authors__ = [

    22     # alphabetical order by last name, please

    23     '"David Anderson" <dave@natulte.net>',

    24     ]

    25 

    26 # The magic escape sequence understood by modern terminal emulators to

    27 # configure fore/background colors and other basic text display

    28 # settings.

    29 _ANSI_ESCAPE = '\x1b[%dm'

    30 

    31 

    32 # Some intrnal non-color settings that we use.

    33 _RESET = 0  # Reset to terminal defaults.

    34 _BOLD = 1   # Brighter colors.

    35 

    36 

    37 # ANSI color codes.

    38 RED = 31

    39 GREEN = 32

    40 WHITE = 37

    41 

    42 

    43 def _ansi_escape(code):

    44     return _ANSI_ESCAPE % code

    45 

    46 

    47 def colorize(text, color, bold=False):

    48     """Colorize some text using ANSI color codes.

    49 

    50     Note that while ANSI color codes look good in a terminal they look

    51     like noise in log files unless viewed in an ANSI color capable

    52     viewer (such as 'less -R').

    53 

    54     Args:

    55       text: The text to colorize.

    56       color: One of the color symbols from this module.

    57       bold: If True, make the color brighter.

    58 

    59     Returns:

    60       The input text string, appropriately sprinkled with color

    61       codes. Colors are reset to terminal defaults after the input

    62       text.

    63     """

    64     bold = _ansi_escape(_BOLD) if bold else ''

    65     return '%s%s%s%s' % (bold, _ansi_escape(color),

    66                          text, _ansi_escape(_RESET))