Connect

Timeout:

Times out the request in ms, defaulting to 5000. The
method req.clearTimeout() is added to revert this behaviour
programmatically within your application's middleware, routes, etc.

The timeout error is passed to next() so that you may customize
the response behaviour. This error has the .timeout property as
well as .status == 503.

Number ms
returns Function

Source

module.exports = function timeout(ms) {
  ms = ms || 5000;

  return function(req, res, next) {
    var id = setTimeout(function(){
      req.emit('timeout', ms);
    }, ms);

    req.on('timeout', function(){
      if (res.headerSent) return debug('response started, cannot timeout');
      var err = new Error('Response timeout');
      err.timeout = ms;
      err.status = 503;
      next(err);
    });

    req.clearTimeout = function(){
      clearTimeout(id);
    };

    res.on('header', function(){
      clearTimeout(id);
    });

    next();
  };
};