QUESTION: how self-describe json relates to json-schemas?

[tatitati]

Sorry for the question, I know that iglu-client is trying to add JSON Schema Draft v7 support (https://github.com/snowplow/iglu/issues/303), however in iglu-client i can read that it "Only support Self-describe json." This bring me some questions:

• I'm wondering how different are both, I see that there is an attempt for self-describe-json to support features from json-schemas, so what gives self-describe-json that doesn't give json-schemas?
• Is self-describe-json superseeding json-schema or adding new features like a wrapper?
• why not using json-schema which seems to be the standard?

Sorry for the bunch of questions, is something I couldn't read in the doc so far.

Thanks a lot

[chuwy]

Hey @tatitati! Thanks for your interest!

First, I'd like to address some confusion (which I also had when first stumbled upon Iglu). There are two tightly coupled, but totally opposite kinds of entities:

1. Self-describing JSONs (example). Plain payload that claim that it is valid against some JSON Schema (using schema keyword, not $schema).
2. Self-describing JSON Schemas (example). Plain JSON Schema that has attached meta-data (using self keyword).

These two kinds of entities are tightly coupled and meant to be used together. From schema key in JSON you know what schema you need to use to validate (and do more cool stuff) it. So data always refer to schema.

So to actually address your questions:

Is self-describe-json superseeding json-schema or adding new features like a wrapper?

Self-describing JSONs do neither, but Self-describing shcmeas do latter

why not using json-schema which seems to be the standard?

We are using it, complying all standards (see meta-schema)

[tatitati]

Thanks a lot @chuwy for the great answer, it was really helpful. Also I will close the question, I have all the information I need.

Thanks!