write out the date-time pattern

[delanym]

What exactly is the regex matching pattern for date-time?

The specification simply points to the RFC3339 page. Its not obvious from reading this page how to validate these fields. The page defers to a further ISO standard, it uses a non-machine readable ABNF notation, and it includes extra exceptions.
https://xml2rfc.tools.ietf.org/public/rfc/html/rfc3339.html#anchor14

[karenetheridge]

Not everything can be expressed as a regular expression.

The date-time format ultimately comes from JSON Schema -- https://json-schema.org/draft/2019-09/json-schema-validation.html#rfc.section.7.3.1

[delanym]

How should I validate date-time values?

It seems the only reason to set a format of date-time was to avoid the hassle of putting in the regex. If its not a regular grammar, then what's the point of specifying a format?

[ahx]

@delanym How to validate date-time format is not part of the OpenAPI specification, but it is specified in the JSON Schema specification (see link posted by @karenetheridge or here).

Relying on standard JSON Schema is good, because if you are building a tool on top of OAS, you can use any standards compliant JSON Schema library to handle validation. 🚀 This even got simpler in OAS 3.1.

[delanym]

How did it get simpler in OAS 3.1?

[ahx]

@delanym Whereas before OAS used it's own flavour of JSON Schema that diverged in quite a lot of cases, OAS 3.1 (RC) uses standard JSON Schema (plus a hand full of additional keywords).

[MikeRalphson]

Closing as answered. Thanks all.