const base64 = require('node-base64-image');
// or
import {encode, decode} from 'node-base64-image';

const url = 'https://example.com/test.jpg';
const options = {
  string: true,
  headers: {
    "User-Agent": "my-app"
  }
};

const image = await encode(url, options);
await decode(image, { fname: 'example', ext: 'jpg' });