Re: [Json] JSON Schema Language

[Nico Williams <[e-mail]>]

On Tue, May 07, 2019 at 06:44:49AM +0200, Anders Rundgren wrote:
> On 2019-05-07 00:38, Tim Bray wrote:
> > I mostly fail to understand the debate about jq and integers and so
> > on. Clearly, the following is a valid JSON text and will be parsed
> > successfully by any JSON parser.
> > 
> > {
> >   "foo": 3.0
> > }
> > 
> > I imagine that most schema-driven software would first deserialize
> > it into a tree, probably something like Jackson ObjectMapper's
> > JsonNode, and then apply schema constructs to the tree.   I would
> > hope that a sane schema would accept this whether a top-level "foo"
> > was required to be an integer or double or most other flavors of
> > number, and reject it if "foo" was required to be a string or
> > boolean.
> 
> Here we have a little problem.  There are already quite popular
> parsers out there flagging 3.0 as an invalid integer when explicitly
> parsing for an integer[*].  Personally, I consider this as right thing
> to do in a schema as well.  Letting one or two rotten eggs (=JSON
> serializers that output Numbers that also represent exact integers
> with fractions) set the bar for the other 99.9% doesn't seem right to
> me.

Those parsers are broken.

> > Put another way, no JSON schema spec can change the definition of
> > what JSON is, or make the built-in type system anything but what it
> > is.
> 
> I don't think anybody is actually proposing that; only mapping things
> that doesn't have a specific representation in JSON like integers.

Integers do have a specific representation in JSON, and anything that
precludes generic encoders that might emit 10.0 where a peer parser will
reject that as not-an-integer *is* a change to JSON.

Nico
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