firebase-config.js

const yaml = require('js-yaml');
const fs = require('fs');

const redirectsYaml = fs.readFileSync('./redirects.yaml', 'utf8');
const {redirects: parsedRedirects} = yaml.safeLoad(redirectsYaml);

const firebaseJson = require('./firebase.incl.json');
firebaseJson.hosting.redirects = parsedRedirects.reduce(
  (redirects, redirect) => {
    const type = [301, 302].includes(redirect.type) ? redirect.type : 301;
    if (redirect.source && redirect.destination) {
      redirects.push({
        source: redirect.source,
        destination: redirect.destination,
        type,
      });
    }
    return redirects;
  },
  [],
);
if (process.env.ELEVENTY_ENV === 'prod') {
  const hashListJson = fs.readFileSync('dist/script-hash-list.json', 'utf-8');
  const hashList = JSON.parse(hashListJson);
  firebaseJson.hosting.headers[0].headers.push({
    key: 'Content-Security-Policy',
    value:
      `script-src 'strict-dynamic' ${hashList.join(' ')} ` +
      `'unsafe-inline' http: https:; object-src 'none'; base-uri 'self'; ` +
      `frame-ancestors 'self'; ` +
      `report-uri https://csp.withgoogle.com/csp/webdev`,
  });
  firebaseJson.hosting.headers[0].headers.push({
    key: 'X-Frame-Options',
    value: 'SAMEORIGIN',
  });
}

fs.writeFileSync('./firebase.json', JSON.stringify(firebaseJson, null, 2));