LTR 'feature' and passing date parameters

[Dariusz Wojtas]

Hi,
I am using the LTR functionality (SOLR 7) and need to define a feature that
will check if the given request parameter of type date (ie. '1998-11-23')
matches birthDate in the stored document. Date granularity should be on DAY
level.
Simply:
* if dates match - return 1
* otherwise (birthDate not set, or they do not match) - return 0

I have several features and do run some model that gives me the final
score. I cannot find a way that will calculate value for date related
feature.

Currently i am having problem even with passing the date param, ie
'1998-11-23' to the feature to treat it as a date.

My 'efi.' param for date is defined as follows:
     efi.searchBirthDate=1998-11-23

In my feature I want to compare dates using the ms(x,y) function and check
if they are equal.
     ms(${searchBirthDate}, birthDate)

But I get exception on calculating the feature:
    Invalid Date String:'1998-11-23'

Any idea how to solve such problem?

Best regards,
Dariusz Wojtas