Optional between dates with allow('')

[ugate]

Is it possible to validate between two dates that are optional?

var schema = Joi.object().keys({
   fromDate: Joi.date().max(Joi.ref('toDate')).allow(''),
   toDate: Joi.date().min(Joi.ref('fromDate')).allow('')
});
Joi.validate({ fromDate: new Date(), toDate: '' }, schema, function (err, value) {
    if (err) console.error(err);
    console.dir(value);
});

prints out to the console:

{ [ValidationError: child "fromDate" fails because ["fromDate" references "toDate" which is not a date]]
  name: 'ValidationError',
  details:
   [ { message: '"fromDate" references "toDate" which is not a date',
       path: 'fromDate',
       type: 'date.ref',
       context: [Object] } ],
  _object:
   { fromDate: Sat Oct 24 2015 20:31:20 GMT-0400 (Eastern Daylight Time),
     toDate: '' },
  annotate: [Function] }

[Marsup]

Both dates should be optional ?

[ugate]

Yeah, both dates are optional, but if both dates are given I'd like for them to be constrained to be between one another.

[Kim-Andersen]

Any progress on this? Dealing with exact same problem here.

[Marsup]

Unfortunately I don't see any elegant way to do this other than a full alternative yet.

[lourd]

Could you expand on what you mean by "a full alternative"? I'm trying something like this:

Joi.object({
  after: Joi.alternatives().try([
    Joi.date().iso().max(Joi.ref('before')),
    Joi.date().iso().max('now'),
  ]),
  before: Joi.alternatives().try([
    Joi.date().iso().min(Joi.ref('after')),
    Joi.date().iso(),
  ]),
})

But the the validation is letting after be a Date in the future, and letting before come before after.

My workaround looks like this:

Joi.object({
  after: Joi.date().iso().max('now'),
  before: Joi.when('after', {
    is: Joi.date(),
    then: Joi.date().iso().min(Joi.ref('after')),
    otherwise: Joi.date().iso(),
  }),
})

But this means that if before is present then after must also must be present. Not doing so returns the error message "before" references "after" which is not a date from validation.

[Marsup]

I meant full alternatives of the 4 possible combinations. That is unless you're not dealing with empty strings in which case I have a better solution.

[lourd]

I'm not sure I understand, could you elaborate?

[Marsup]

1st do you have to deal with empty strings or not ?

[lourd]

If before or after are empty strings I would want the validation to strip them or have an error because of them.

[Marsup]

So coming back at the OP, I had the idea to use refs to our advantage, so your example becomes :

var schema = Joi.object().keys({
   fromDate: Joi.date().max(Joi.ref('toDate', { default: new Date(3000, 0, 0), defaultFor: [''] })).empty(''),
   toDate: Joi.date().min(Joi.ref('fromDate', { default: new Date(0, 0, 0), defaultFor: [''] })).empty('')
});
Joi.validate({ fromDate: new Date(), toDate: '' }, schema, function (err, value) {
    if (err) console.error(err);
    console.dir(value);
});

The idea is to have defaults for your refs that would match anything, so some kind of absolute min and max dates.

@lourd does that solve your use case as well ?

[lourd]

Maybe? My use case doesn't care about empty strings, I would want that treated the same as if the value weren't present.

defaultFor seems like an awkward option for a ref. You're providing a default value for another key. For me, if after is present, then before should have a minimum of after. Otherwise, there should be no minimum for before. Vice versa for after. The changes/example you made don't do that, rather they substitute the ref with dates far in the past or in the future.