Function tryServeStaticAsset

scripts/dev-server.cjs:165–208

(request, response, distDir)

}

function tryServeStaticAsset(request, response, distDir) {
  const requestUrl = request.url || '/';
  const pathname = decodeURIComponent(requestUrl.split('?')[0]);
  const prefix = '/_next/static/';

  if (!pathname.startsWith(prefix)) {
    return false;
  }

  const staticRoot = path.join(process.cwd(), distDir, 'static');
  const relativePath = pathname.slice(prefix.length);
  const filePath = path.join(staticRoot, relativePath);

  if (!filePath.startsWith(staticRoot + path.sep)) {
    response.statusCode = 403;
    setNoStoreHeaders(response);
    response.end('Forbidden');
    return true;
  }

  let stat;
  try {
    stat = statSync(filePath);
  } catch {
    return false;
  }

  if (!stat.isFile()) {
    return false;
  }

  response.statusCode = 200;
  response.setHeader('Content-Type', getContentType(filePath));
  response.setHeader('Content-Length', stat.size);
  setNoStoreHeaders(response);

  if (request.method === 'HEAD') {
    response.end();
    return true;
  }

  createReadStream(filePath).pipe(response);
  return true;
}

function proxyToInternal(request, response, host, port) {
  const proxyRequest = http.request(