Extract SVG shapes from a draw.io mxlibrary file

shape-extract.mjs

import fs from 'node:fs'
import path from 'node:path'

let opts = {}
process.argv.forEach(function (val, index, array) {
  if (val.startsWith('--')) {
    opts[val.slice(2)] = process.argv[index+1]
  }
});

const { from, out } = opts

if (!from || !out) {
    console.warn("usage: extract --from file.xml --out ./shapes ")
    process.exit(1)
}

let input = fs.readFileSync(from).toString()
let data = JSON.parse(input.replaceAll(/<\/?mxlibrary>/g, ''))

if (!fs.existsSync(out)) {
    fs.mkdirSync(out)
}

console.log("Exporting shapes to %s", out)

data.forEach((shape, i) => {
    let src = Buffer.from(shape.data.split(',')[1], 'base64').toString()
    fs.writeFileSync(path.join(out, `shape-${i}.svg`), src, 'utf8')
})

console.log("Done.")