code: function getHandlerExporter (app) {
    if (!isServerApp(app)) {
      return null;
    }
  
    // `app` is an express-like server app.
    return function (method, path, parameters) {
      // Support restify.
      if (method === 'del' && ('delete' in app)) {
        method = 'delete';
      }
      app[method](path, parameters.handler);
    };
  }
docs: Try to create a handler exporter function for a given server app.