ComfyUI-Downloader

A powerful and user-friendly extension for ComfyUI that adds a built-in model downloader with a sleek modal interface. Download models, LoRAs, VAEs, and other assets directly from URLs without leaving ComfyUI.

Features

• 🚀 High-Speed Downloads: Optimized for datacenter connections with parallel downloading (8 connections, 32MB chunks)
• 📦 Queue Management: Download multiple files with automatic queue processing
• 🎯 Smart Integration: Detects missing models from your workflow and suggests downloads
• 🔄 Real-time Progress: Live progress tracking with download speed and ETA
• 🛡️ Security: Built-in path traversal protection and file validation
• 📂 Auto-Organization: Downloads files to the correct ComfyUI folders (checkpoints, loras, VAEs, etc.)
• ⏸️ Download Control: Cancel downloads in progress with queue management
• 🎨 Clean UI: Modal-based interface that integrates seamlessly with ComfyUI

👉 Watch Full Video

Models urls are loaded from workflow or https://github.com/Comfy-Org/ComfyUI-Manager/blob/main/model-list.json

Installation

Method 2: Manual Installation

1. Navigate to your ComfyUI custom nodes directory:

   cd ComfyUI/custom_nodes/

2. Clone this repository:

   git clone https://github.com/romandev-codex/ComfyUI-Downloader.git

3. Install dependencies:

   cd ComfyUI-Downloader
   pip install -r requirements.txt

4. Restart ComfyUI

Requirements

• Python 3.8+
• ComfyUI
• Dependencies:
  • aiohttp
  • hf_transfer

Usage

Basic Usage

1. Click the "Downloader" button in the ComfyUI interface (next to the settings button)
2. The downloader modal will open
3. Paste a model URL in the URL field
4. Select the destination folder (checkpoints, loras, vae, etc.)
5. Enter a filename (supports subfolders like subfolder/model.safetensors)
6. Click "Download"

Advanced Features

Subfolder Support

You can organize downloads into subfolders:

my-loras/character-lora.safetensors
sdxl/checkpoints/my-model.safetensors

File Override Protection

• If a file already exists, you'll be prompted for confirmation
• Choose to override or cancel the download

Missing Model Detection

• The extension scans your workflow for missing models
• Missing models are highlighted in the UI for quick downloading

Queue Management

• Multiple downloads are queued automatically
• One download processes at a time for optimal performance
• Cancel queued or active downloads anytime

Configuration

The extension uses optimized settings for datacenter connections:

• Chunk Size: 32MB (balanced for 500MB to 30GB+ files)
• Parallel Connections: 8 (optimal for datacenter bandwidth)

These settings are configured in the __init__.py file and can be adjusted if needed.

Supported Folders

The downloader supports all standard ComfyUI model directories:

• checkpoints
• loras
• vae
• upscale_models
• embeddings
• controlnet
• clip_vision
• And more...

Security

ComfyUI-Downloader includes multiple security measures:

• Path traversal attack prevention
• Filename validation (no backslashes, dots, or escape sequences)
• Path resolution verification
• Only downloads to configured ComfyUI model directories

API

The extension provides REST API endpoints for programmatic access:

Start Download

POST /{API_PREFIX}/server_download/start
{
  "url": "https://example.com/model.safetensors",
  "save_path": "checkpoints",
  "filename": "model.safetensors",
  "override": false
}

Cancel Download

POST /{API_PREFIX}/server_download/cancel
{
  "download_id": "checkpoints/model.safetensors"
}

WebSocket Events

• server_download_progress: Real-time progress updates
• server_download_complete: Download completion notification
• server_download_error: Error notifications

Development

Project Structure

ComfyUI-Downloader/
├── __init__.py              # Main extension logic and API endpoints
├── requirements.txt         # Python dependencies
├── web/
│   ├── css/
│   │   └── downloader.css  # UI styling
│   └── js/
│       ├── downloader.js   # Extension initialization
│       └── UI.js           # Modal UI implementation
└── README.md

Building and Testing

1. Make your changes
2. Restart ComfyUI to reload the extension
3. Test in the browser console for any errors

Troubleshooting

Button Doesn't Appear

• Ensure ComfyUI is fully loaded before looking for the button
• Check browser console for JavaScript errors
• Verify the extension is in the custom_nodes directory

Downloads Fail

• Check internet connectivity
• Verify the URL is accessible
• Check browser console and ComfyUI terminal for error messages
• Ensure you have write permissions to the ComfyUI directories

Slow Download Speeds

• The extension is optimized for datacenter connections
• Adjust CHUNK_SIZE and NUM_CONNECTIONS in __init__.py if needed
• Check your network bandwidth and latency

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

License

MIT License - see LICENSE file for details

Credits

Created for the ComfyUI community to make model management easier and more efficient.

Support

If you encounter issues or have suggestions:

• Open an issue on GitHub
• Check existing issues for solutions
• Provide error messages and browser console logs when reporting bugs