JSON-LD vs JSON for info file

[jpstroop]

Related tickets:

• The @context uri should resolve, and give a context document. #2 (@context URI should resolve)
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JSON-LD has a different media type than regular JSON (application/ld+json vs application/json). Which should the server provide with the info.json document? Metadata API is explicit that it should be ld+json, but may be json. Neither spec recommends .jsonld extension.

According to the JSON-LD specification (and clarification from the editors), processors receiving application/json documents should ignore @context and instead look for a link header pointing to a context document. Otherwise for application/ld+json, they should use @context and must ignore a header. At the moment we put @context in the document, but return application/json for compatibility with existing frameworks and systems.

See: http://lists.w3.org/Archives/Public/public-linked-json/2014Feb/0001.html

_Solution:_ You must support both application/json and application/ld+jsonld. Content will be the same, different mime types. URI is just info.json, and do content negotiation to get JSON-LD, otherwise assume JSON.

_Action:_ Rob to write the prose for this