MONGOOSE ERRORS

 MONGOOSE ERRORS CAN BE MANIPULATED.

const handleValidationErr = (err) => {
  console.log("It is a validation error. Refer to the rules");
  console.dir(err.message);
  return err;
};
app.use((err, req, res, next) => {
  console.log(err.name);
  if (err.name === "ValidationError") {
    err = handleValidationErr(err);
    next(err);
  }
});



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