Server-side Image generation for Polotno

Is it possible to generate images from polotno JSON on the backend?

Yes. The is polotno-node package for such a use case.

Using polotno-node you can use most of Polotno Store API. The common usage is image generation from JSON generated by polotno:

const fs = require('fs');

// import polotno-node API

const { createInstance } = require('polotno-node');

async function run() {

// create working instance

const instance = await createInstance({

// to create your own API key please go here: https://polotno.dev/cabinet

key: 'nFA5H9elEytDyPyvKL7T',

});

// load sample json

const json = JSON.parse(fs.readFileSync('polotno.json'));

// here you can manipulate JSON somehow manually

// for example replace some images or change text

// then we can convert json into image

const url = await instance.jsonToDataURL(json);

// prepare base64 string to save as localfile

var base64Data = url.replace(/^data:image\/png;base64,/, '');

// save it to local file

require('fs').writeFileSync('out.png', base64Data, 'base64');

// close instance

instance.close();

}

run();