Re: [core] Modernized Link Format

Klaus Hartke <hartke@projectcool.de> Fri, 12 October 2018 08:48 UTC

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From: Klaus Hartke <hartke@projectcool.de>
Date: Fri, 12 Oct 2018 10:47:20 +0200
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Subject: Re: [core] Modernized Link Format
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Christian Amsüss wrote:
> > 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.
>
> That avoids the formal mess, but creates a practical one. Code is out
> there that produces documents in "link-format;version=any" (documents
> that work with both 6690 and modernized). Moving everything over to
> link-format;version=2 at ct=39 creates formal clarity and practical
> non-interoperability for them.

I was more thinking of keeping the media type and content format ID
and changing the payload to opt-in to the new semantics.

For example, the link in this representation of
<coap://example.com:1234/.well-known/core>...

    <foo/bar>

...would resolve to <coap://example.com:1234/foo/bar>, and the link in
this representation...

   \v2, <foo/bar>

would resolve to <coap://example.com:1234/.well-known/foo/bar>.

> CoRAL -- yes, that's why I asked about whether we can have a preview
> release of CoRAL without the research-ish forms parts in it. If CoRAL
> were a document heading towards WGLC, I'd be happy to recommend CoRAL
> for RD use on all sides, and state that link-format can be used per
> RFC6690 but is limited as outlined in an appendix, and power users
> should use CoRAL or better.

Let's accelerate CoRAL then.

Klaus