2. Format attributes
The "format" keyword is defined to allow interoperable semantic validation for
a fixed subset of values. Currently only date, date-time, and time
attributes are defined and follow RFC 3339 specifications. Validation rules
5.6 and the additional restriction rules 5.7 have
been implemented.
Any other format attributes will not perform validation.
Note: Leap seconds cannot be predicted far into the future and are therefore allowed for every value validated against "time".