express error handling middleware

gistfile1.js

// example based on @AriPorad Expressjs - All Routes Are 404
// http://stackoverflow.com/questions/18406591/expressjs-all-routes-are-404/18407658#18407658

// custom error handler
// put this at the end of your middleware chain and handle errors however you want
app.use(function (err, req, res, next) {
  if (err.message
    && (~err.message.indexOf('not found')
    || (~err.message.indexOf('Cast to ObjectId failed')))) {
    res.status(404).render('404', { url: req.originalUrl })
  } else if(err){
    console.error(err.stack)
    res.status(500).render('500')
  };
  // no errors
  next();
})