Function downloadFileHelper

backend-api/utils/disk-utils.ts:21–140

(
  url: string,
  dirPath: string,
  filePath: string,
  cookies?: string
)

  'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/122.0.0.0 Safari/537.36';

export const downloadFileHelper = async (
  url: string,
  dirPath: string,
  filePath: string,
  cookies?: string
): Promise<void> => {
  ensureDirectoryExistence(filePath);

  // Delete any existing partial download
  if (fs.existsSync(filePath)) {
    fs.unlinkSync(filePath);
  }

  const headers = {
    'User-Agent': USER_AGENT,
    Accept: '*/*',
    'Accept-Language': 'en-US,en;q=0.9',
    'Accept-Encoding': 'identity', // Prevent gzip to avoid corruption
    Connection: 'keep-alive',
    Range: 'bytes=0-', // Support range requests
    Referer: 'https://www.tiktok.com/',
    ...(cookies ? { Cookie: cookies } : {}),
  };

  return new Promise((resolve, reject) => {
    const handleResponse = (response: http.IncomingMessage) => {
      // Handle redirects
      if (response.statusCode === 301 || response.statusCode === 302) {
        const redirectUrl = response.headers.location;
        if (!redirectUrl) {
          reject(new Error('Redirect location not found'));
          return;
        }
        logger.info(`Following redirect to: ${redirectUrl}`);
        const redirectReq = https.get(redirectUrl, { headers }, handleResponse);
        redirectReq.on('error', reject);
        return;
      }

      // Check content type
      const contentType = response.headers['content-type'];
      if (
        !contentType?.includes('video') &&
        !contentType?.includes('audio') &&
        !contentType?.includes('image')
      ) {
        reject(new Error(`Unexpected content type: ${contentType}`));
        return;
      }

      // Check content length
      const contentLength = parseInt(
        response.headers['content-length'] || '0',
        10
      );
      if (contentLength === 0) {
        reject(new Error('Content length is 0'));
        return;