Express Status Guard

Inspirated by Haskells monad guards, this middleware frees you from the burden of repetitive error handling in your callbacks and let's you focus on your business logic.

Just app.use(guard()).

Before

dbRequest.do(function (err, data) {
  if (err) return res.send(500);
  dbRequest2.do(data, function (err, data2, data3) {
    if (err) return res.status(500).send('Uh! Fail.');
    dbRequest3.do(data2, data3, function (err, data4) {
      if (err) return res.status(500).json({error: 'meeh'});
      res.json({result: data4});
  });
});

After

dbRequest.do(res.guard(500, function (data) {
  dbRequest2.do(data, res.guard(500, 'Uh! Fail.', function (data2, data3) {
    dbRequest3.do(data2, data3, res.guard(500, {error: 'meeh'}, function (data4) {
      res.json({result: data4});
    }));
  }));
}));