Re: [core] Modernized Link Format

Klaus Hartke <hartke@projectcool.de> Thu, 11 October 2018 13:29 UTC

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From: Klaus Hartke <hartke@projectcool.de>
Date: Thu, 11 Oct 2018 15:28:34 +0200
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Subject: Re: [core] Modernized Link Format
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Christian Amsüss wrote:
> We've ruled out c) over the last year b/c it means that features of the
> RD will not be available (ie. some links can not be expressed in any
> serialization format)

Just to clarify: You can always, write link targets as "URI" or
"path-absolute" [RFC3986], right? (That's not very efficient but not
not expressible.)

> Among b and a, a was picked because hopes were that would allow for the
> fastest progress of RD which is way behind schedule; also, it allows
> doing b1 later easily. I'm all for doing any of the b options, but I
> don't rather not have them delay the RD.

It creates a situation we really should avoid: A representation
format, identified by the "application/link-format" media type, that
changes its semantics depending on the context in which it is used (RD
or legacy application).

Thinking about it a bit more, I only see two ways forward: Keep the
"application/link-format" media type and add a version indicator to
the representation format that prevents legacy applications from
applying the wrong semantics. Or use an entirely different media type
(e.g., "application/link-format+cbor" with fixed rules,
"application/coral+cbor").

Klaus