Quick documentation on how to use the receipt printer API via receiptprinterd.

• Source code: https://codeberg.org/dma/receiptprinterd

The usages below assume you're using the nixos-media-box machine. If you're running anything else, simply replace the hostname.

To print a simple string:

curl -L http://nixos-media-box.local/receipt -F "text=Hello, world!"

To print a file:

curl -L http://nixos-media-box.local/receipt -F "text=@/path/to/file"

To print from stdin:

echo "Hello, world!" | curl -L http://nixos-media-box.local/receipt -F "text=@-"

To print an image:

curl -L http://nixos-media-box.local/receipt/image -F "image=@/path/to/image.jpg"

Any image format supported by Pillow will be supported here as well. This includes JPEG and PNG.

If the image is too wide, it will be automatically shrunk.

If the image is in landscape orientation, it will automatically be rotated to fit the receipt. There is currently no way to turn this off.

If the image is too dark, you can set the brightness filter:

curl -L http://nixos-media-box.local/receipt/image \
   -F "image=@/path/to/image.jpg" \
   -F "brightness=0.85"

For all parameters, see the API documentation for POST /image.

To print a QR code encoding some text:

curl -L http://nixos-media-box.local/receipt/qr -F "text=youtu.be/xuzKafChH7k"

By default, after each printing request, the server will command the printer to cut the paper. To change this behavior, add:

-F cut=false

You may also manually command the printer to cut via a request:

curl -L -X POST http://nixos-media-box.local/receipt/cut

See http://nixos-media-box.local/receipt/docs.