Logarithmic

🍎 Get it on the Mac App Store

---

Logarithmic is fully open source (Apache 2.0 license) and always will be. The Mac App Store version is available for $9.99 to provide a signed, notarized build that runs without security warnings on macOS. This also helps support ongoing development and covers the cost of the Apple Developer Program.

You can always build from source for free using the instructions below!

---

The ultimate cross-platform log tailing application with intelligent grouping, syntax highlighting, and session management.

🚀 Why Logarithmic is the Best Log Tailing Application Ever

🎯 Intelligent Log Management

• Session Management - Save and restore complete log tracking sessions with window positions
• Wildcard Support - Track log files with patterns like app-*.log and automatically switch to newest files
• Smart Grouping - Organize related logs into groups with tabbed or combined views
• Window Snapping - Auto-snap windows together for perfect multi-monitor layouts
• F3 Window Recovery - Press F3 to instantly move all windows to your cursor when monitors disconnect

🎨 Beautiful & Customizable Interface

• Syntax Highlighting - Automatic colorization of errors (red), warnings (orange), and verbose logs (gray)
• Custom Fonts - Modern, readable typography with Michroma, Oxanium, and Red Hat Mono
• Adjustable Font Sizes - Separate controls for log content, UI elements, and status bars
• Theme Support - Customizable color schemes for different log levels

⚡ Powerful Real-Time Features

• Live Mode - Auto-scroll to latest logs with visual indicators
• Pause/Resume - Freeze updates while keeping the tail active in background
• Go Live Button - Instantly jump back to the latest logs
• Clear on Demand - Clear display without affecting the underlying log stream
• Log Filtering - Real-time text filtering with case-insensitive option

🔧 Advanced Capabilities

• Multi-Window Design - Each log opens in its own independent window
• File State Management - Handles creation, deletion, rotation, and missing files gracefully
• Combined View - Merge multiple logs into a single interleaved stream with source labels
• Tabbed View - View multiple logs in tabs with individual controls
• Persistent Settings - All preferences, window positions, and sessions saved automatically
• Multi-Monitor Support - Seamless operation across multiple displays with F3 recovery for undocking

🤖 AI Integration

• MCP Server - Built-in Model Context Protocol server for AI agent integration
• Claude Desktop Support - Connect Claude to your logs for intelligent analysis
• Log Metadata - Add human-readable IDs and descriptions for better AI understanding
• Search & Query Tools - AI agents can list, search, and retrieve log content
• Thread-Safe Architecture - MCP server runs asynchronously without blocking the UI

🔄 Auto-Update Notifications

• Version Check - Automatically checks for updates on startup
• Manual Check - "Check for Updates" button in Settings
• Non-Blocking - Background thread keeps UI responsive
• Smart Detection - Detects dev builds vs release builds

💡 Lost Your Windows After Undocking?

If you undock your laptop or disconnect monitors and your log windows are stuck on a disconnected display:

1. Press F3 on the main window (or any visible window)
2. All windows instantly move to your mouse cursor location
3. Redistribute them on your current monitor setup

No need to close and reopen the application or manually hunt for off-screen windows!

Quick Links

• Release Process - How to build and release
• Changelog - Version history and release notes
• Coding Guidelines - Python development standards
• MCP Server Quick Start - Get started with AI integration
• MCP Server Details - Technical documentation for MCP server
• App Encryption Documentation - Encryption/export usage details

📸 Screenshots

Single Log Window - Live Tailing

Real-time log tailing with syntax highlighting, pause/resume, and live mode indicator

Grouped Logs - Tabbed View

Multiple related logs organized in tabs with individual controls for each

Grouped Logs - Combined View

Interleaved log streams with source labels for easy correlation

🤖 AI Integration with MCP Server

Logarithmic now includes a built-in Model Context Protocol (MCP) server that allows AI agents like Claude Desktop to directly access and analyze your logs!

Quick Start

1. Enable MCP Server: Go to Settings tab → Check "Enable MCP Server"
2. Restart Application: Changes take effect after restart
3. Configure Claude Desktop: Add Logarithmic to your Claude Desktop MCP servers
4. Ask Claude: "List all available logs" or "Search for errors in my application logs"

What You Can Do

• 📋 List Logs: AI can see all your tracked logs with descriptions
• 🔍 Search: Find patterns across all logs instantly
• 📖 Read Content: AI can retrieve and analyze full log content
• 🐛 Debug: Ask AI to find errors, analyze patterns, or suggest fixes

Learn More: See MCP Quick Start Guide for detailed setup instructions.

📦 Installation

Download Pre-Built Binaries

Download the latest release for your platform from the Releases page:

• Windows: Logarithmic-Windows.zip - Extract and run Logarithmic.exe
• macOS: Logarithmic-macOS.zip - Extract and run Logarithmic.app
• Linux: Logarithmic-Linux.tar.gz - Extract and run ./Logarithmic

No installation required - just download, extract, and run!

Development Setup

Prerequisites

• Python 3.11 or higher
• pip

Installation

1. Clone the repository

   git clone <repository-url>
   cd logarithmic

2. Create a virtual environment

   python -m venv .venv

3. Activate the virtual environment

   • Windows: .venv\Scripts\activate
   • macOS/Linux: source .venv/bin/activate

4. Install dependencies

   pip install -r requirements.txt

5. Install development dependencies (optional)

   pip install -e ".[dev]"

6. Set up pre-commit hooks (recommended)

   pre-commit install

   This will automatically run ruff format and ruff --fix on your code before each commit, ensuring consistent code style.

Running the Application

python -m logarithmic

Or from the source directory:

python src/logarithmic/__main__.py

Running Tests

pytest

With coverage:

pytest --cov=src/logarithmic --cov-report=term-missing

📖 Usage Guide

Getting Started

1. Add a log file:

   • Enter the path to a log file in the input box
   • Click "Add" or press Enter
   • Supports wildcards: C:\logs\app-*.log or /var/log/app-*.log

2. Open a viewer:

   • Double-click a log file in the list to open its viewer window
   • Windows automatically position themselves with smart snapping

Session Management

Located at the top of the main window:

• Save Session: Preserves all tracked logs, groups, and window positions
• Duplicate Session: Create a copy of the current session
• Delete Session: Remove a saved session
• Session Dropdown: Quickly switch between saved sessions

Log Groups

Organize related logs together:

1. Create a Group: Click "New Group" and give it a name
2. Assign Logs: Right-click a log → "Assign to Group"
3. View Group: Double-click the group to open the group window
4. Switch Modes: Toggle between Tabbed and Combined view

Tabbed Mode: Each log in its own tab with individual controls
Combined Mode: All logs merged into one stream with source labels

Window Controls

Every log window includes:

• Pause Button: Freeze updates while keeping the tail active
• Clear Button: Clear the display (history preserved in tabbed mode)
• Go Live Button: Appears when scrolled up - click to jump to latest logs
• Status Bar: Shows line count, live/scroll mode, and pause status
• Set Default Size: Save current window size as default for new windows

Settings Tab

Customize your experience:

• Log Content Font Size: 6-24pt for log text
• UI Elements Font Size: 6-18pt for buttons and labels
• Status Bar Font Size: 6-14pt for status text
• MCP Server: Enable AI agent integration (see MCP Quick Start)
  • Enable/disable MCP server
  • Configure binding address (default: 127.0.0.1)
  • Configure port (default: 3000)
• About: View current version and check for updates
• Theme Colors: Customize error, warning, verbose, and default colors (coming soon)

Window Recovery (F3 Hotkey)

Problem: Undocked your laptop or disconnected a monitor? Windows stuck on a disconnected display?

Solution: Press F3 on the main window to instantly relocate all windows to your mouse cursor!

How it works:

1. Move your mouse to where you want your windows
2. Press F3 on the main window
3. All windows (main + log viewers + groups) cascade from your cursor position
4. Rearrange them as needed on your current monitor setup

This feature is a lifesaver for laptop users who frequently dock/undock or switch between monitor configurations.

Keyboard Shortcuts

• Enter: Add log file from input box
• Double-Click: Open log viewer or group window
• F3: Move all windows to cursor position (essential for multi-monitor setups!)
• Scroll Up: Exit live mode (shows Go Live button)
• Scroll to Bottom: Re-enter live mode automatically

Syntax Highlighting

Logs are automatically colorized based on keywords:

• 🔴 Red: error, fatal, critical, exception, fail, failed, failure
• 🟠 Orange: warning, warn, caution, deprecated
• ⚪ Gray: verbose, debug, trace
• Default: Normal log text

🏗️ Architecture

The application follows a clean architecture with separation of concerns:

Core Components

• main_window.py: Main control window with session and group management
• log_viewer_window.py: Individual log viewer windows with ContentController
• log_group_window.py: Group windows with tabbed and combined modes
• content_controller.py: Unified content display and control management
• log_manager.py: Centralized log buffer and subscriber management
• file_watcher.py: File watching and tailing logic using watchdog
• wildcard_watcher.py: Wildcard pattern matching and file switching
• log_highlighter.py: Syntax highlighting for log content
• settings.py: Session, preferences, and theme management
• fonts.py: Custom font loading and management

MCP Server Components

• mcp_server.py: Model Context Protocol server for AI agent integration
• mcp_bridge.py: Thread-safe bridge between LogManager and MCP server
• Exposes logs as MCP resources with tools for listing, searching, and retrieving content
• Runs asynchronously in separate thread without blocking the UI
• See MCP Server Details for architecture details

File State Management

The file watcher implements a robust three-state system:

1. Non-Existent: Watch parent directory for file creation
2. Exists: Tail the file and watch for deletion/move
3. Deleted/Moved: Close handles and return to state 1

This ensures graceful handling of log rotation, file system changes, and wildcard pattern matching.

Subscriber Pattern

The LogManager implements a publisher-subscriber pattern:

• Log viewers and group windows subscribe to specific log files
• New content is broadcast to all subscribers
• Efficient memory management with centralized buffering
• Supports multiple subscribers per log file

✨ Key Features in Detail

Session Management

• Auto-save: Last used session loads automatically on startup
• Multiple Sessions: Switch between different project configurations
• Complete State: Saves logs, groups, window positions, and settings
• Duplicate & Delete: Easily manage your session library

Wildcard Support

• Pattern Matching: Use * and ? in file paths
• Auto-Switch: Automatically follows the newest matching file
• Rotation Handling: Seamlessly handles log rotation
• Visual Indicator: Shows current file in window title

Log Grouping

• Flexible Organization: Group related logs by project, service, or environment
• Two View Modes: Tabbed for individual focus, Combined for correlation
• Independent Controls: Each tab has its own pause/clear/live controls
• Source Labels: Combined mode prefixes each line with the source filename

Smart Window Management

• Auto-Snapping: Windows snap to each other within 20 pixels
• Position Memory: Window positions saved per log/group
• Default Sizing: Set your preferred default window size
• Multi-Monitor: Works seamlessly across multiple displays
• F3 Recovery: Press F3 to move all windows to cursor when monitors are disconnected

Syntax Highlighting

• Real-Time: Applied as logs stream in
• Customizable: Theme colors configurable per session
• Performance: Efficient Qt-based syntax highlighter
• Keyword-Based: Matches common logging patterns

📁 Project Structure

logarithmic/
├── .github/
│   ├── workflows/
│   │   ├── ci.yml              # Continuous integration
│   │   └── release.yml         # Automated releases
│   └── RELEASE.md              # Release documentation
├── Docs/
│   ├── Changelog.md            # Version history and release notes
│   ├── CodingGuidelines.md     # Development standards
│   ├── MCP_Quickstart.md       # MCP server quick start guide
│   └── MCP_Details.md          # MCP server technical details
├── fonts/
│   ├── Michroma/               # Title font
│   ├── Oxanium/                # UI font
│   └── Red_Hat_Mono/           # Monospace log font
├── images/
│   ├── main_window.png         # Screenshots
│   ├── single_window.png
│   ├── grouped_tabbed.png
│   └── grouped_combined.png
├── src/
│   └── logarithmic/
│       ├── __init__.py
│       ├── __main__.py         # Application entry point
│       ├── content_controller.py   # Unified content display
│       ├── exceptions.py       # Custom exceptions
│       ├── file_watcher.py     # File tailing logic
│       ├── fonts.py            # Font management
│       ├── log_group_window.py # Group window UI
│       ├── log_highlighter.py  # Syntax highlighting
│       ├── log_manager.py      # Log buffer management
│       ├── log_viewer_window.py    # Single log window
│       ├── main_window.py      # Main control window
│       ├── mcp_bridge.py       # MCP server bridge
│       ├── mcp_server.py       # MCP server implementation
│       ├── settings.py         # Session & preferences
│       ├── version_checker.py  # Auto-update version checking
│       └── wildcard_watcher.py # Wildcard pattern support
├── .gitignore
├── LICENSE                     # Apache 2.0
├── Logarithmic.spec           # PyInstaller configuration
├── pyproject.toml             # Project metadata
├── requirements.txt           # Dependencies
└── README.md

🎯 Use Cases

Logarithmic is perfect for:

• Software Development: Monitor application logs during development and debugging
• DevOps: Track multiple service logs across microservices architectures
• System Administration: Watch system logs, web server logs, and application logs simultaneously
• Game Development: Monitor Unreal Engine, Unity, or custom game engine logs
• CI/CD Pipelines: Track build and deployment logs in real-time
• Testing: Monitor test execution logs with automatic error highlighting
• Production Monitoring: Keep an eye on production logs with session-based organization
• AI-Assisted Debugging: Use Claude or other AI agents to analyze logs and find issues faster

🤝 Contributing

All contributions must follow the standards defined in Docs/CodingGuidelines.md.

Key requirements:

• Use ruff for linting and formatting
• Use mypy for type checking
• Include type hints for all functions
• Write tests for new functionality
• Follow Google-style docstrings

📄 License

Copyright 2025 Willem J Hattingh

Licensed under the Apache License, Version 2.0 - See LICENSE file for details.

🙏 Acknowledgments

Fonts

Logarithmic uses three beautiful open-source fonts:

• Michroma - Window titles (SIL OFL 1.1)
• Oxanium - UI elements (SIL OFL 1.1)
• Red Hat Mono - Log content (SIL OFL 1.1)

All fonts are licensed under the SIL Open Font License 1.1.

---

Made with ❤️ for developers who love clean, powerful log tailing.