Filter special chars such as color codes from shell output

Question

I ran shell commands in python, logged their outputs into files and finally showed on a web page. however the color style chars of command outputs were also logged. is there a way to filter out the color style chars or display them correctly on web pages? Many thanks!

Output log:

" 22200K .......\u001b[0m\u001b[91m... .......... ...\u001b[0m\u001b[91m.\u001b[0m\u001b[91m...... .........\u001b[0m\u001b[91m.\u001b[0m\u001b[91m \u001b[0m\u001b[91m.\u001b[0m\u001b[91m.\u001b[0m\u001b[91m.\u001b[0m\u001b[91m.\u001b[0m\u001b[91m...... 50% 28.6K 12m55s"

the real text:

[INFO][88] 22250K .......... .......... .......... .......... .......... 50% 35.8K 12m53s

Answer 1

In the unlikely case when you have xterm256 color codes as well, this will filter both 'normal' ansi and xterm256 ansi codes:

import re
print re.sub(r'\x1b(\[.*?[@-~]|\].*?(\x07|\x1b\\))', '', a)

or in a slightly less obfuscated and more readable form:

'(' + CSI + '.*?' + CMD + '|' + OSC + '.*?' + '(' + ST + '|' + BEL + ')' + ')'

Complete code with tests:

import re

tests = [
    u"22200K .......\u001b[0m\u001b[91m... .......... ...\u001b[0m\u001b[91m.\u001b[0m\u001b[91m...... .........\u001b[0m\u001b[91m.\u001b[0m\u001b[91m \u001b[0m\u001b[91m.\u001b[0m\u001b[91m.\u001b[0m\u001b[91m.\u001b[0m\u001b[91m.\u001b[0m\u001b[91m...... 50% 28.6K 12m55s",
    u"=\u001b[m=",
    u"-\u001b]23\u0007-",
]

def trim_ansi(a):
    ESC = r'\x1b'
    CSI = ESC + r'\['
    OSC = ESC + r'\]'
    CMD = '[@-~]'
    ST = ESC + r'\\'
    BEL = r'\x07'
    pattern = '(' + CSI + '.*?' + CMD + '|' + OSC + '.*?' + '(' + ST + '|' + BEL + ')' + ')'
    return re.sub(pattern, '', a)

for t in tests:
    print trim_ansi(t)