new JSON Schema Draft version support

[CagtayFabry]

I was wondering what the plans are for supporting new jsonschema specifications in the future.

Currently the asdf-standard is described as implementing the "JSON Schema Draft 4" specification. The asdf python package now works with jsonschema>=3.x which afaik supports JSON Schema up to Draft 7. What would be needed regarding the asdf package but also the asdf-standard to support JSON Schema Draft 7 as well? (unfortunately my knowledge of asdf internals is lacking) Would this require major changes/reworks?

I am interested in Draft 7 mostly because of conditional schema evaluation (if/then/else) which I think would also be a great addition to asdf.

related: https://github.com/asdf-format/asdf-standard/issues/243

[eslavich]

I'm not aware of any specific plans, but this issue has revived discussion. There have been breaking changes in the JSON Schema spec between Draft 4 and Draft 7 so we would need to support both for a time. Off the top of my head, these are the steps required:

• Create a new version of yaml-schema that incorporates JSON Schema Draft 7
• Create new versions of all other asdf-standard schemas that declare the new yaml-schema version as their metaschema and follow the new spec
• Make an asdf-standard release
• Add code to this library to examine the $schema field of each schema and use Draft 4 or Draft 7 validators accordingly
• It's going to lead to confusing errors if someone references a Draft 4 schema from Draft 7 (and vice versa), so we should probably add some special handling around that as well