YouTube.js/scripts/get-agents.js

import { fetch } from 'undici';
import { gunzip } from 'zlib';
import { dirname, resolve } from 'path';
import { fileURLToPath } from 'url';
import { writeFile } from 'fs/promises';

(async () => {

  const __dirname = dirname(fileURLToPath(import.meta.url));

  const buf = await (await fetch('https://github.com/intoli/user-agents/blob/master/src/user-agents.json.gz?raw=true')).arrayBuffer();
  const bytes = new Uint8Array(buf);

  // Only get desktop and mobile agents
  const allowed_agents = new Set([
    'desktop',
    'mobile'
  ]);

  const decompressed = await new Promise((resolve, reject) => {
    gunzip(bytes, (err, result) => {
      if (err) {
        reject(err);
      } else {
        resolve(result.buffer);
      }
    });
  });

  const contents = new TextDecoder().decode(decompressed);

  const agents = JSON.parse(contents);

  if (!Array.isArray(agents)) {
    throw new Error('Invalid user-agents.json');
  }

  const agentsByDevice = agents.reduce((acc, agent) => {
    const device = agent.deviceCategory;
    if (!allowed_agents.has(device))
      return acc;
    if (!acc[device]) {
      acc[device] = [];
    }
    // We dont want to massive of a list of agents for each device
    if (acc[device].length <= 25) acc[device].push(agent.userAgent);
    return acc;
  }, {});

  await writeFile(resolve(__dirname, '..', 'src', 'utils', 'user-agents.ts'), `/* eslint-disable */\n/* Generated file do not edit */\nexport default ${JSON.stringify(agentsByDevice, null, 2)} as { desktop: string[], mobile: string[] };`);

})();