taildir/README.md

A simple directory watcher that recursively monitors file changes using only native Node.js libraries

# taildir

A lightweight Node.js directory watcher that monitors file changes recursively and outputs new content as it's appended - similar to `tail -f` but for entire directories.

## Features

- Recursively watches all files in a directory tree
- Outputs only new content when files grow (like `tail -f`)
- Filter by file extensions (e.g., watch only `.log` files)
- Ignores hidden files and temporary files
- Lightweight - uses only native Node.js libraries
- Trims empty lines from output

## Installation

```bash
npm install -g taildir
```

Or run directly with `npx`:

```bash
npx taildir <directory>
```

## Usage

Watch the current directory:
```bash
taildir
```

Watch a specific directory:
```bash
taildir /path/to/directory
```

Watch only specific file extensions:
```bash
taildir /path/to/directory -e js,ts,json
taildir --ext log,txt
```

### Example Output

```
Starting to watch: /home/user/logs
Press Ctrl+C to stop

==> /home/user/logs/app.log <==
[2024-01-15 10:30:45] Application started
[2024-01-15 10:30:46] Connected to database

==> /home/user/logs/error.log <==
[2024-01-15 10:31:02] ERROR: Failed to process request
```

## How It Works

- When starting, `taildir` records the current size of all files
- When a file grows, it reads and displays only the new content
- New files created while watching will show their complete content
- Files that shrink (truncated) are tracked but don't produce output
- Hidden files (starting with `.`) are ignored

## Use Cases

- Monitor application logs across multiple files
- Watch output directories for generated content
- Track changes in data files
- Debug file-writing applications

## Requirements

- Node.js >= 14.0.0

## License

MIT