Add version identifier

[joostholslag]

I'd love the ability to specify the version of a schema.
It should identify the version of the current schema (not of the specification/meta-schema.
It should be recommended to use semantic versioning of the schema.
Similar to OpenAPI info_object.version: https://spec.openapis.org/oas/latest.html#info-object
It would help to express openEHR archetype models for clinical data in something standard like json-schema.

It could be solve by introducing a new keyword like "version" where the value is a string with recommended formatting in "x.x.x".

p.s. I'm sorry if this has been asked and answered. a search for 'version' produced many results, the first two pages were not relevant and 'semantic version' didn't produce any relevant results.

[gregsdennis]

Hey there. Thanks for the suggestion. I'm pretty sure we've received this request before, but it's really been in more of a "how do I manage my schema version?" format.

I recommend doing what we actually do with the meta-schemas: embed the version into the $id URI. This promotes schemas never changing and supports a better transition story to the new version. When you have a new version, you publish it separately with a new $id. This give the consumers of your older schema an opportunity to update to the new one.

You can still use semver in the $id if you like. With the upcoming spec release, we've settled on something like /<version-number>/<release-year>, using an integer version as a semver "major" value to indicate compatibility between releases. This allows our users to also use /<version-number> to just get the latest compatible release for the version.

I'll mark this as a proposal and leave it open to get others' opinions as well.

[awwright]

@gregsdennis has a good suggested alternative.

Your idea could be pursued as part of a generic mechanism for metadata (perhaps a variation on "$comment" that accepts a JSON-LD blob), but anything more specific than that doesn't make sense.