SaveImageS3 R2 Sidebar

ComfyUI-SaveImageS3

Save generated ComfyUI images to S3-compatible storage such as Cloudflare R2, MinIO, AWS S3, or other S3 API services.

This fork rewrites the extension for current ComfyUI Desktop/manual installs and adds an asset sidebar with preview thumbnails, public links, copy/open actions, persistent config, and upload history.

Features

• Save Image S3 output node.
• Saves a local PNG copy like ComfyUI's native Save Image node.
• Uploads the PNG and a JSON metadata file to S3-compatible storage.
• Builds a public URL from Public URL + object key, which works well with Cloudflare R2 custom domains.
• Randomizes uploaded S3 object names to avoid predictable public URLs.
• Shows uploaded assets in a left sidebar with local preview thumbnails.
• Provides Copy and Open actions for every uploaded public link.
• Stores config and upload history outside workflow JSON, so credentials are not embedded in workflows.

Installation

Clone this repository into ComfyUI/custom_nodes/ComfyUI-SaveImageS3 and install dependencies in the ComfyUI Python environment:

pip install -r requirements.txt

Restart ComfyUI after installation.

Configuration

Open the SaveImageS3 sidebar from the S3 rail button, the ComfyUI settings entry, or the canvas context menu.

Fields:

• Scheme: Friendly name, for example r2.
• Endpoint: S3 API endpoint, for example <account>.r2.cloudflarestorage.com.
• Bucket: Bucket name.
• Access Key: S3 access key.
• Secret: S3 secret key. The UI does not return the stored secret after save.
• Public URL: Public asset base URL, for example https://img.example.com/.
• Region: Region string, or auto for services such as R2.
• HTTPS: Whether to use HTTPS when connecting to the S3 API.

Config and upload history are stored under this plugin's data/ directory:

• data/config.json
• data/history.json

Do not commit data/config.json; it contains credentials.

Usage

Add Save Image S3 to your workflow and connect an IMAGE input.

Inputs:

• filename_prefix: Local output filename prefix, same purpose as the native Save Image node.
• object_prefix: Optional S3 object key prefix, for example comfyui/outputs.

On execution, the node:

1. Saves the image to ComfyUI's local output directory.
2. Uploads the PNG to S3.
3. Uploads a JSON metadata file next to it.
4. Records the public link in history.
5. Shows the latest upload in the SaveImageS3 sidebar.

The local filename remains the normal ComfyUI output filename for preview/history. The uploaded S3 object name is randomized, so public URLs do not expose predictable counters such as ComfyUI_00026_.png.

Cloudflare R2 Notes

R2's S3 put_object response does not return your custom-domain public URL. Set Public URL to the R2 custom domain base URL, and this extension will join it with the uploaded object key.

Example:

Public URL: https://img.example.com/
Object key: comfyui/ComfyUI_00001_.png
Result URL: https://img.example.com/comfyui/ComfyUI_00001_.png

Tests

python -m pytest tests -v
python -m compileall -q .
node --check web/plugin.js