[BUG] Terminal colors encodings visible in app logs #1366

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1. cray44 commented on May 8, 2026

   

   cray44

   on May 8, 2026

   Last edited by cray44

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   Hi I'd like to take a look at this. It looks like subprocess output containing ANSI escape sequences is being passed through to the web app logs without stripping. I'm planning to add an ANSI-sanitizing utility and apply it at the Terraform/Ansible output capture points. Will submit a PR once I have a working fix.
2. janderik commented on Jul 22, 2026

   

   janderik

   on Jul 22, 2026

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   This is a common issue when terminal output with ANSI color codes is displayed in a web interface. The color codes (like \x1b[31m for red) are not being stripped before rendering.

   Solutions:

   1. Strip ANSI codes before logging:

   import re
   
   def strip_ansi_codes(text: str) -> str:
       """Remove ANSI escape codes from text."""
       ansi_escape = re.compile(r'\x1b\[[0-9;]*m')
       return ansi_escape.sub('', text)
   
   # Use when logging
   logger.info(strip_ansi_codes(output))

   2. Use a logging filter:

   import logging
   import re
   
   class ANSI stripFilter(logging.Filter):
       def __init__(self):
           super().__init__()
           self.ansi_escape = re.compile(r'\x1b\[[0-9;]*m')
       
       def filter(self, record):
           record.msg = self.ansi_escape.sub('', record.msg)
           return True
   
   # Add to logger
   logger.addFilter(ANSI stripFilter())

   3. Disable colors in non-TTY environments:

   import sys
   import os
   
   def should_use_colors():
       """Check if we should use colors (TTY, not piped, etc.)."""
       return (
           hasattr(sys.stdout, 'isatty') and 
           sys.stdout.isatty() and 
           os.environ.get('TERM') != 'dumb'
       )
   
   # Disable colors when not in a terminal
   use_colors = should_use_colors()

   4. For subprocess output:

   import subprocess
   
   result = subprocess.run(
       command,
       capture_output=True,
       text=True,
       env={**os.environ, 'TERM': 'dumb'}  # Force no colors
   )

   The cleanest solution is usually #1 (strip at log time) or #3 (prevent colors in non-TTY environments).

   Happy to help review a PR implementing any of these approaches!