applog 1.0.1

a logger for applications, not libs

applog

A beautiful, zero-dependency logging formatter for Python with colors, emoji support, clickable file links, and intelligent number highlighting.

Features

• 🎨 Colored output by log level (respects NO_COLOR and FORCE_COLOR standards)
• 😊 Smart emoji support - clean emoji-only output with automatic fallback for incompatible terminals
• 🔗 Clickable file links (OSC 8 hyperlinks) - Ctrl+Click to open in your editor
• 🔢 Automatic number highlighting - numbers stand out in your logs
• 📦 Zero external dependencies - pure Python standard library
• 🚀 No pre-rendering - logs wrap correctly when terminal resizes
• ⚙️ Environment variable aware - follows NO_COLOR, FORCE_COLOR, NO_EMOJI, FORCE_EMOJI conventions

Installation

uv add applog

Quick Start

from applog import logger

logger.debug("Debug message")
logger.info("Info message")
logger.warning("Warning message")
logger.error("Error message")
logger.critical("Critical message")

With colors and emojis (default on supported terminals):

Thu 12:42:25 🐛 <module>: Debug message
Thu 12:42:26 ℹ️ <module>: Info message
Thu 12:42:26 ⚠️ <module>: Warning message
Thu 12:42:26 ❌ <module>: Error message
Thu 12:42:26 🔥 <module>: Critical message

Without color/emoji support (automatic fallback):

Thu 12:42:25 DBG <module>: Debug message
Thu 12:42:26 INF <module>: Info message
Thu 12:42:26 WRN <module>: Warning message
Thu 12:42:26 ERR <module>: Error message
Thu 12:42:26 CRT <module>: Critical message

Changing Date Format

from applog import root_logger

# Change to 24-hour time without seconds
root_logger.handlers[0].formatter.datefmt = '%H:%M'

# Change to full datetime
root_logger.handlers[0].formatter.datefmt = '%Y-%m-%d %H:%M:%S'

Customizing Colors

from applog import Color, root_logger

# Modify color codes (ANSI escape sequences)
Color.INFO = '\033[94m'  # Bright blue for INFO

Customizing Emojis

from applog import logging, root_logger

# Modify emoji mapping (access via formatter)
formatter = root_logger.handlers[0].formatter
if hasattr(formatter, 'LEVEL_EMOJIS'):
    formatter.LEVEL_EMOJIS['INFO'] = '📘'  # Change INFO emoji
    formatter.LEVEL_EMOJIS['CRITICAL'] = '💀'  # Change CRITICAL emoji

Environment Variables

Variable	Effect
NO_COLOR	Disable all colored output
FORCE_COLOR	Force colored output even in non-TTY
NO_EMOJI	Disable emoji output (uses text fallback)
FORCE_EMOJI	Force emoji output even in non-TTY

Example:

# Disable emoji output
NO_EMOJI=1 python myapp.py

# Force emoji even when logging to a file
FORCE_EMOJI=1 python myapp.py > output.log

Terminal Support

Emoji support is automatically detected and works on:

• ✅ VS Code integrated terminal
• ✅ Windows Terminal
• ✅ macOS Terminal.app and iTerm2
• ✅ Modern Linux terminals (GNOME Terminal, Konsole, etc.)

Fallback to text labels occurs automatically on:

• Legacy Windows terminals (CMD, PowerShell classic)
• Linux TTY consoles (no emoji fonts)

Using with Standard Logging

applog configures the root logger, so any standard logging calls will use the same formatting:

import logging
from applog import logger

# These will all have the same beautiful formatting
logging.warning("Root logger warning")
custom_logger = logging.getLogger(__name__)
custom_logger.info("Custom logger info")

Advanced Usage

Adding Handlers

from applog import root_logger
import logging

# Add file handler
file_handler = logging.FileHandler('app.log')
file_handler.setFormatter(logging.Formatter('%(asctime)s - %(levelname)s - %(message)s'))
root_logger.addHandler(file_handler)

Creating Child Loggers

from applog import logger

module_logger = logger.getChild('module_name')
module_logger.info("This will inherit parent settings")

Notes

• For end-user applications only: Only use this library in end-user applications. Libraries should normally only call standard logging.getLogger(__name__) and not mess with formatting - let the final application control the formatting.
• Terminal-only: This formatter is specifically for console output.
• The module configures the root logger on import - import it early in your application.
• Hyperlinks use OSC 8 sequences - won't work in very old terminals

Why applog?

• vs rich.logging: Logs adapt when you resize your terminal (no pre-rendering)
• vs loguru: Works with all standard logging calls out of the box
• The result: Beautiful, clickable, dependency-free logging with emoji support that just works