How to Joi-Allow an empty Date String [Joi]

as the title states, how to allow an empty Date-String through Joi validation.

When adding:

Date: ""

it gets the Issue: message: ""Date" must be a number of milliseconds or valid date string"

with this Joi-Validation:

"Date": Joi.date().required().allow("").allow(null).options(validationErrors);

Question: How can an empty Date-String be allowed through Joi validation?

EDIT: By removing: .required() and or adding .default("") i do get another error, when adding Date: "", Cannot set parameter at row: 1. Wrong input for DATE type

Answer

Valid: Either new Date() or "" (empty string)

joi version 17.2.1

const joi = require('joi');

const schema = joi.object().keys({
  "Date": joi.alternatives([
    joi.date(),
    joi.string().valid('')
  ]).required()
}).required();

// success
const value = {
  "Date": "",
};

// success
const value = {
  "Date": new Date(),
};

// error
const value = {
  "Date": null,
};

// error
const value = {

};

// error
const value = {
  "Date": "invalid string"
};


const report = schema.validate(value);
console.log(report.error);