replace UUID with distinguishable emojis

uuid4sym.py

#!/usr/bin/python3
# -*- coding: utf-8 -*-
"""uuid4sym - replace UUID version 4 to an easily distinguishable symbol

When looking at a long log file with some UUID4 uuids, you'll have a hard time
distinguishing between two UUIDs.

Both 26cb1b84-7748-11e9-9437-2bf0efaa1b2e and 2725e8de-7748-11e9-a9c8-f3e5d10ab3d6
looks similar to the human eye.

uuid4sym would replace each UUID with a symbol which is easier to distinguish.

uuid4sym replaces the first 50 UUIDs with animals emojis which are not similar.
The next UUIDs will be replaced with UXXX with a ascending serial number and
different color.

You can disable emojis with -e/--no-emojis, and disable colors with -C/--no-colors

"""

import re
import sys
import optparse

COLORS = range(31, 38)

ESC = '\033['


def color(i, txt):
    'color returns txt surrounded by terminal escape which colors it with color i'
    return '{e}{i}m{txt}{e}0m'.format(e=ESC,
                                      i=COLORS[0] + i % len(COLORS),
                                      txt=txt)


class Animal(object):
    'Animal will replace a given UUID, with the same emoji'
    animals = '🐭🐿🦔🦇🐍🐥🐦🐧🐹🐘🦏🐰🦁🐅🦛🦍🐠🐡🦐🐚🐌🦞🦅🦉🦜🦢🦚🏇🦗🎠♘♞🐽🐾👣🐢🦀🐈🐀🦋🐝🐞🐜🐛🕷🕸🦂🦎🦟🦠🐙🌰🌱🌽🐨'

    def __init__(self, colors=True, emojis=True):
        self.dict = {}
        self.i = 0
        self.colors = colors
        if not emojis:
            self.animals = ''

    def __repr__(self):
        return 'Animal(%d UUIDs)'%self.i

    def __str__(self):
        return 'Animal(%s)'%self.dict

    def size(self):
        'size returns the number of different UUIDs stored'
        return self.i

    def get(self, uuid):
        'get accepts UUID and replaced it with always the same symbol'
        animal = self.dict.get(uuid)
        if not animal:
            if self.i >= len(self.animals):
                index = self.i - len(self.animals)
                text = 'U%03d' % index
                if self.colors:
                    animal = color(index, text)
                else:
                    animal = text
            else:
                animal = self.animals[self.i]
            self.i += 1
        self.dict[uuid] = animal
        return animal


def main():
    'main function, reads from stdin, replaces UUIDv4 with symbols'
    parser = optparse.OptionParser(usage="usage: %prog [options]")
    parser.add_option("-C",
                      "--no-colors",
                      action="store_true",
                      default=False,
                      dest='no_colors',
                      help='do not use terminal colors')
    parser.add_option("-e",
                      "--no-emojis",
                      action="store_true",
                      default=False,
                      dest='no_emojis',
                      help='do not replace uuid with utf-8 emojis')
    options, args = parser.parse_args()
    if args:
        sys.stderr.write("No args are allowed")
        return

    animals = Animal(colors=not options.no_colors,
                     emojis=not options.no_emojis)
    uuid_re = re.compile('[a-f0-9]{8}(?:-[a-f0-9]{4}){3}-[a-f0-9]{12}')

    try:
        while True:
            line = sys.stdin.readline()
            if not line:
                break
            last_i = 0
            for match in uuid_re.finditer(line):
                start, end = match.span()
                sys.stdout.write(line[last_i:start])
                sys.stdout.write(animals.get(match.group(0)))
                last_i = end
            sys.stdout.write(line[last_i:])
            sys.stdout.flush()
    except KeyboardInterrupt:
        sys.stderr.write('Exit by Ctrl-C')


if __name__ == '__main__':
    main()