Re: [JSON] Survey for design requirements

On 03/09/11 04:45, Andy Seaborne wrote:
>> There are two things that happened above:
>>
>> 1. Frank's system provides a default context that changes all of his
>>     plain old JSON into RDF.
>> 2. The person interfacing with Frank's system provides their own
>>     set of keywords that expand to full URIs - enabling any triple
>>     to be stored alongside Frank's regular account information.
>>
>> So, the transition from plain old JSON to JSON+RDF happens smoothly.
>> Frank makes this transition because it makes his REST services far more
>> flexible than just plain old JSON.
> 
> I hope any mapping is the serialization. It's important that if the
> format is a graph, or triples, then the representation is
> self-contained. If it points to an external context then the meaning can
> be changed by some external change.

The mapping is in the serialization in some cases ("context") and/or
assumed by the Web Service in other cases ("default context"). You can
see an example of a "default context" in JSON-LD:

http://json-ld.org/spec/ED/20110201/#an-example-of-a-default-context

The "default context" can be provided to the initialization code of the
JSON-LD processor. A "context" can be provided by the person authoring
JSON and overrides mappings previously established by the "default
context". So #1 above is achieved via a "default context" and #2 above
is achieved via a "context" specified in the serialization.

It is a best practice to always include all information about mappings
in the serialized data at the top level of the serialization. That is,
all JSON-LD serializations SHOULD include a list of mappings used in the
JSON-LD serialization. However, Web Services MAY also specify a "default
context" in the case where they have to support legacy clients that
don't know anything about JSON-LD, but do know how to speak the normal
JSON protocol used by the service.

Did that make sense?

-- manu

-- 
Manu Sporny (skype: msporny, twitter: manusporny)
President/CEO - Digital Bazaar, Inc.
blog: Payment Standards and Competition
http://digitalbazaar.com/2011/02/28/payment-standards/

Received on Wednesday, 9 March 2011 20:03:52 UTC