codes.js

function create(req, res, next) {
  Placement.create(req.body, function (err, placement) {
    if (err) {
      if (err instanceof RecordNotFound) {
        res.status(status(404)).send(); 
      }
      else if (err instanceof ValidationFailed) {
        res.status(status(400)).send();
      }
      else {
        // internal error
        res.status(status(500)).send();
      }
    } 
    else {
      res
        .status(status['Created'])
        .json(placement);
    }
  });
}