Fixing JSON

I’ve edited a couple of the JSON RFCs, and am working on the design of a fairly complex DSL, so I think I can claim to have dug deeper in the JSON mines than most. We can easily agree on what’s wrong with JSON, and I can’t help wondering if it’d be worth fixing it.

Major irritant: Commas · Hand-editing JSON may not be the most important way of interacting with it, but it shouldn’t be as hard as it is. In particular, when I’m moving things around in a chunk of JSON I can never, as in NEVER, get the commas right.

The fix is easy: Just remove them. They’re inessential to the grammar, just there for JavaScript compatibility.

Alternatively, you could make them optional, or you could allow a comma after the last member of an array or object. But, in Internet protocols, less is more. Just nuking the commas and requiring whitespace separators is the best way forward. Like so:

{
  "IDs": [116 943 234 38793]
  "Settings": { "Aperture": 2.8 "Shutter speed": "1/250" }
}

Irritant: Timestamps · JSON is chiefly used, these days, in HTTP requests and results. Among the RESTful APIs that I can think of, exactly zero don’t have timestamps.

This one is easy to fix: Just introduce them already. Use the well-established well-debugged RFC 3339 format, insisting on capital T and Z.

Strictly speaking you don’t need any syntax because grammatically a timestamp can’t be a number and a number can’t be a timestamp. However, I think a syntactic signal might be nice: I was thinking of prefixing timestamps with “@”, like so:

{ "Capture Time": @2016-08-01T18:15:00Z }

Here’s the canonical example of a JSON object, originally due to Doug Crockford, as modified in RFC 7159, and slightly extended to illustrate the cleanups I’m talking about.

 {
     "Image": {
         "Width":  800
         "Height": 600
         "Title":  "View from 15th Floor"
         "Thumbnail": {
             "Url":    "http://www.example.com/image/481989943"
             "Height": 125
             "Width":  100
         }
         "Animated" : false
         "Capture Time": @2016-08-01T18:15:00Z
         "IDs": [ 116 943 234 38793 ]
       }
   }

Major irritant: Schemas · Specifying a JSON DSL is a major pain in the ass. JSON Schema will get you part of the way there, but if you use its modularity features, centered around “anyOf”, it becomes very hard for implementations to generate helpful high-quality error messages. The world has room for something considerably better, and I may be driven to a proposal myself.

But those syntax-irritant fruits around commas and timestamps hang so low that it’d be lovely to grab ’em. I raised the idea in the IETF JSON working group and the consensus seemed to be “It’s not that terrible, there are too many markup-language proposals already, just live with it.” Feaugh.

Contributions

Comment feed for ongoing:

From: Paul Hoffman (Aug 20 2016, at 11:11)

Sounds like you are inventing an input language for something that could be converted to JSON. Or CBOR. :-)