ApiClient.js

function formatUrl(path) {
  const adjustedPath = path[0] !== '/' ? '/' + path : path;
  if (__SERVER__) {
    // Prepend host and port of the API server to the path.
    return 'http://localhost:' + config.apiPort + adjustedPath;
  }
  // Prepend `/api` to relative URL, to proxy to API server.
  return '/api' + adjustedPath;
}