Proposal: Support "date-time-local" and "time-local" format

[yassun7010]

I’m an author of Tombi (TOML Language Server).

In order to validate TOML's LocalDateTime and LocalTime, I want to add format for date-time and time without a time zone.

I know that it’s the problems of the TOML, but it’s useful for JSON too.

For example, what about date-time-local and time-local?

[jdesrosiers]

The format keyword isn't limited to the ones defined in the spec. You can use custom formats. It sounds like your real issue is with whatever JSON Schema implementation you're using to do that validation. Some implementations provide a way to plugin support for your custom formats. Some collect format as an annotation allowing you to do the validation as an additional step. You'll need to figure out what your implementation supports and maybe ask them for additional features if necessary.

In any case, I suggest adding you formats to the registry currently maintained by OpenAPI. https://spec.openapis.org/registry/format/

[yassun7010]

Thanks for replying!

My problem is that I am in a state of variability in the naming defined in the custom formats.

Custom formats like partial-datetime, local-datetime, datetime-local, etc. are implemented by the library author.
However, since datetime and time are included in the JSON Schema specification, I believe it would be beneficial to the community as a whole if they were added there.

Ideally, I would like to see them added to the JSON Schema specification, which is also linked to in the OpenAPI documentation you provided as a reference link.

What better place to propose this than here?

[jdesrosiers]

We try not to add new formats. We haven't for a while and it's not because we haven't gotten proposals like this. If we add every format that could be beneficial, the list would get out of control very quickly. That's why our approach has been to recommend that people add their proposed formats to the registry. People should consider the registry just as authoritative as the JSON Schema specification. It's optional to implement the formats in the JSON Schema spec, so there's no practical difference whether it's in the spec or the registry.

The only difference is that implementations are more likely to support formats if they are in the spec. There's currently an effort to move the registry from OpenAPI to JSON Schema. That might give people more confidence in using it. It would probably be a good idea to move all formats from the spec to the registry. Then there would really be no difference.

[yassun7010]

Thanks for the detailed explanation.

I will try your suggestion to add the format to the registry.