Bundle static files in Motoko canisters

ic-bundle-static-files.mjs

#!/usr/bin/env node

import {writeFile} from 'fs/promises';

import {Blob} from 'node:buffer';

import fetch from 'node-fetch';

const fetchData = async (url) => {
  const response = await fetch(url);

  if (!response || !response.ok) {
    throw new Error(`Data ${url} cannot be fetched.`);
  }

  return response.text();
};

const template = ({variable, content}) => `module {
  public let ${variable}: [Nat8] = [${content}];
}`;

const generate = async ({url, dest, variable}) => {
  const data = await fetchData(url);

  const blob = new Blob([data], {
    type: 'text/plain'
  });

  await writeFile(dest, template({variable, content: [...new Uint8Array(await blob.arrayBuffer())]}));
};

(async () => {
  try {
    const assets = [
      {
        url: 'https://raw.githubusercontent.com/deckgo/ic-kit/main/dist/robots.txt',
        dest: './canisters/src/storage/assets/storage.robots.txt.mo',
        variable: 'robots_txt'
      },
      {
        url: 'https://raw.githubusercontent.com/deckgo/ic-kit/main/dist/build/index.css',
        dest: './canisters/src/storage/assets/storage.index.css.mo',
        variable: 'index_css'
      }
    ];

    await Promise.all(assets.map((asset) => generate(asset)));
  } catch (err) {
    console.error(err);
  }
})();