Update to Draft 4 of JSON-Schema

[zuiderkwast]

What needs to be done

• Small adjustments of current code (some renamed things: divisibleBy to multipleOf, readonly to readOnly, ...)
• Add the new things that are not yet implemented to the README.

Considerations

• Should we keep backwards compatibility with draft 3 when possible (keep renamed and/or deleted things: readonly, divisibleBy, extends, disallow, type=any) or drop them?
• A flag for which draft to validate against? (Intuitively, I doen feel it's an attractive thing to do.)

Change logs for draft 4

Core schema:

• Initial draft.
• Salvaged from draft v3.
• Mandate the use of JSON Reference, JSON Pointer.
• Define the role of "id". Define URI resolution scope.
• Add interoperability considerations.

Validation schema:

• Initial draft.
• Salvaged from draft v3.
• Redefine the "required" keyword.
• Remove "extends", "disallow"
• Add "anyOf", "allOf", "oneOf", "not", "definitions",
  "minProperties", "maxProperties".
• "dependencies" member values can no longer be single strings;
  at least one element is required in a property dependency
  array.
• Rename "divisibleBy" to "multipleOf".
• "type" arrays can no longer have schemas; remove "any" as a
  possible value.
• Rework the "format" section; make support optional.
• "format": remove attributes "phone", "style", "color"; rename
  "ip-address" to "ipv4"; add references for all attributes.
• Provide algorithms to calculate schema(s) for array/object
  instances.
• Add interoperability considerations.

Hyper schema:

• Resolution of link URIs ("href") is now affected by rel="self"
  links on the instance
• Define "title" for LDOs
• Use URI Templates for the "href" property
• Split hyper-schema definition out from main schema.
• Capitalised the T in "encType", and the O in "readOnly"
• Moved "mediaType" and "contentEncoding" to the new "media"
  property (renamed "type" and "binaryEncoding")
• Added "mediaType" property to LDOs
• Replaced "slash-delimited" fragment resolution with "json-
  pointer".
• Added "template" LDO attribute.
• Improved wording of sections.

[varnerac]

Regarding the considerations listed, I think using the $schema keyword and supporting URIs is a sensible solution.

http://tools.ietf.org/id/draft-zyp-json-schema-04.html#rfc.section.6

[Cy6erBr4in]

this is ongoing

[wpjunior]

+1

[voluntas]

+1

[richcarl]

Closing. See for-GET/jesse#4