dalog 0.1.2

Your friendly terminal logs viewer

dalog - Your friendly terminal logs viewer

dalog is a terminal-based log viewing application built with Python and Textual. It provides advanced features for viewing, searching, and analyzing log files with a modern, keyboard-driven interface optimized for developer workflows.

Features

• Live Search: Real-time filtering
• Exclusion System: Filter out unwanted log entries with persistent patterns and regex
• Smart Styling: Pattern-based syntax highlighting with regex support
• Live Reload: Automatically update when log files change (like tail -f)
• Visual Mode: Vi-style visual line selection with clipboard support
• HTML Rendering: Render HTML tags in logs (configurable tags)
• ** Vim Keybindings**: Full vim-style navigation with customizable keybindings
• ** Configurable**: Extensive configuration options via TOML files
• CLI Exclusions: Filter logs directly from command line with --exclude parameter
• Theme Support: Choose from built-in Textual themes via CLI

Installation

Via pip (recommended)

pip install dalog

Development Installation

# Clone the repository
git clone https://github.com/mwmdev/dalog.git
cd dalog

# Install in development mode
pip install -e .

# Or with development dependencies
pip install -e ".[dev]"

Quick Start

Basic Usage

# View a single log file
dalog application.log

# Start with search pre-filled
dalog --search ERROR application.log

# Exclude unwanted log levels
dalog --exclude "WARNING" application.log

# Load only last 1000 lines
dalog --tail 1000 large-application.log

# Use custom configuration
dalog --config ~/.config/dalog/custom.toml app.log

# Use a specific Textual theme
dalog --theme gruvbox error.log

CLI Arguments

Required Arguments

• log_file - The path to the log file you want to view
  • Must be an existing, readable file
  • Example: dalog application.log or dalog /var/log/app.log

Optional Arguments

• --config / -c - Specify a custom configuration file

  • Type: Path to existing TOML configuration file
  • Example: dalog --config ~/.config/dalog/custom.toml app.log
  • If not specified, dalog searches for config files in the standard locations

• --search / -s - Start dalog with a search term already applied

  • Type: String (search term or regex pattern)
  • Example: dalog --search "ERROR" app.log
  • Example: dalog -s "user_id=\\d+" app.log (regex pattern)

• --tail / -t - Load only the last N lines from the file

  • Type: Integer (number of lines)
  • Useful for large log files to improve startup performance
  • Example: dalog --tail 1000 large-app.log
  • Example: dalog -t 500 app.log

• --theme - Set the visual theme for the application

  • Type: String (theme name)
  • Available themes include: textual-dark, textual-light, nord, gruvbox, catppuccin-mocha, dracula, tokyo-night, monokai, flexoki, catppuccin-latte, solarized-light
  • Example: dalog --theme gruvbox app.log
  • Example: dalog --theme nord error.log

• --exclude / -e - Exclude lines matching the specified pattern

  • Type: String (pattern or regex)
  • Can be used multiple times to exclude multiple patterns
  • Patterns are case-sensitive and support regex
  • Applied in addition to config file exclusions
  • Example: dalog --exclude "DEBUG" app.log
  • Example: dalog -e "WARNING" -e "INFO" app.log
  • Example: dalog --exclude "ERROR.*timeout" app.log (regex)

• --version / -V - Display the version number and exit

  • Example: dalog --version
  • Example: dalog -V

Default Keybindings

Key	Action
/	Open search
ESC	Close search/cancel/exit visual mode
j/k	Navigate down/up
h/l	Navigate left/right
g/G	Go to top/bottom
Ctrl+u/Ctrl+d	Page up/down
V	Enter visual line mode (vi-style selection)
v	Start selection at cursor (in visual mode)
y	Yank/copy selected lines to clipboard (in visual mode)
r	Reload file
L	Toggle live reload
w	Toggle text wrapping
e	Manage exclusions
q	Quit

Visual Mode

DaLog supports vi-style visual line selection:

1. Press V (or enter a line number and press V) to enter visual line mode
2. Use j/k to navigate to the desired starting line (cursor shown with underline)
3. Press v to start selection from the current cursor position
4. Use j/k to extend the selection up/down
5. Press y to yank (copy) selected lines to clipboard
6. Press ESC to exit visual mode without copying

Configuration

DaLog looks for configuration files in the following order:

1. Command-line specified: --config path/to/config.toml
2. $XDG_CONFIG_HOME/dalog/config.toml
3. ~/.config/dalog/config.toml
4. ~/.dalog.toml
5. ./config.toml (current directory)

Example Configuration

[app]
default_tail_lines = 1000
live_reload = true
case_sensitive_search = false
vim_mode = true

[keybindings]
search = "/"
reload = "r"
toggle_live_reload = "L"
toggle_wrap = "w"
quit = "q"
show_exclusions = "e"
scroll_down = "j"
scroll_up = "k"
scroll_left = "h"
scroll_right = "l"
scroll_home = "g"
scroll_end = "G"

[display]
show_line_numbers = true
wrap_lines = false
max_line_length = 1000
visual_mode_bg = "white"  # Background color for visual mode selection

[styling.patterns]
error = { pattern = "(?i)error", background = "red", color = "white" }
warning = { pattern = "(?i)warning", background = "yellow", color = "black", bold = true }
info = { pattern = "(?i)info", color = "blue" }

[styling.timestamps]
iso_datetime = { pattern = "\\d{4}-\\d{2}-\\d{2}T\\d{2}:\\d{2}:\\d{2}", color = "cyan" }

[html]
# Configure which HTML tags to render in logs
enabled_tags = ["b", "i", "em", "strong", "span", "code", "pre"]
strip_unknown_tags = true

[exclusions]
patterns = ["DEBUG:", "TRACE:"]
regex = true
case_sensitive = false

Styling System

DaLog supports powerful regex-based styling patterns:

[styling.custom]
# Highlight IP addresses
ip_address = { pattern = "\\b(?:[0-9]{1,3}\\.){3}[0-9]{1,3}\\b", color = "magenta" }

# Highlight URLs
url = { pattern = "https?://[\\w\\.-]+", color = "blue", underline = true }

# Highlight email addresses
email = { pattern = "\\b[A-Za-z0-9._%+-]+@[A-Za-z0-9.-]+\\.[A-Z|a-z]{2,}\\b", color = "cyan" }

# Custom application-specific patterns
user_id = { pattern = "user_id=\\d+", color = "green", bold = true }

Development

Setting up the development environment

# Clone the repository
git clone https://github.com/mwmdev/dalog.git
cd dalog

# Install development dependencies
pip install -e ".[dev]"

# Run tests
pytest

# Run linting
black src/
mypy src/
pylint src/

Project Structure

dalog/
├── src/dalog/          # Main package
│   ├── app.py          # Textual application
│   ├── cli.py          # Click CLI interface
│   ├── config/         # Configuration management
│   ├── core/           # Core functionality
│   ├── widgets/        # Custom Textual widgets
│   └── styles/         # CSS styles
├── tests/              # Test suite
├── docs/               # Documentation
└── pyproject.toml      # Project configuration

Contributing

Contributions are welcome! Please feel free to submit a Pull Request. For major changes, please open an issue first to discuss what you would like to change.

1. Fork the repository
2. Create your feature branch (git checkout -b feature/amazing-feature)
3. Commit your changes (git commit -m 'Add some amazing feature')
4. Push to the branch (git push origin feature/amazing-feature)
5. Open a Pull Request

License

This project is licensed under the MIT License - see the LICENSE file for details.

Acknowledgments

• Built with Textual - an amazing TUI framework
• Inspired by traditional Unix tools like tail, less, and grep
• Thanks to all contributors and users