Highlight terms in stdin with different colors.

highlight.py

#!/usr/bin/env python
"""
# highlight

Highlight terms in stdin with different colors.

Example usage:

    $ tail -f /some/log_file | highlight batch3 slave master darwin
"""
import sys


colors_map = {'black': '0;30',
              'blue': '0;34',
              'green': '0;32',
              'cyan': '0;36',
              'red': '0;31',
              'purple': '0;35',
              'brown': '0;33',
              'light_gray': '0;37',
              'dark_gray': '1;30',
              'light_blue': '1;34',
              'light_green': '1;32',
              'light_cyan': '1;36',
              'light_red': '1;31',
              'light_purple': '1;35',
              'yellow': '1;33',
              'white': '1;37'}

for potentially_bland_color in ('black', 'light_gray', 'dark_gray', 'white'):
    del colors_map[potentially_bland_color]

def color_string(color):
    return '\033[%sm' % color

colors = [color_string(color) for color in colors_map.itervalues()]
reset = color_string(0)


def colorize(input_string, color):
    return ''.join((color, input_string, reset))


def highlight(terms, text):
    for index, term in enumerate(terms):
        color = colors[index % len(colors)]
        text = text.replace(term, colorize(term, color))
    return text


if __name__ == '__main__':
    if len(sys.argv) < 2:
        print 'Specify some terms to highlight.'
        sys.exit(1)

    for line in sys.stdin:
        sys.stdout.write(highlight(sys.argv[1:], line))