W3C home > Mailing lists > Public > public-grddl-wg@w3.org > February 2007

Re: GRDDL Link header design alternatives (#issue-http-header-links)

From: Harry Halpin <hhalpin@ibiblio.org>
Date: Fri, 09 Feb 2007 13:06:12 -0500
Message-ID: <45CCB814.5030801@ibiblio.org>
To: Dan Connolly <connolly@w3.org>, public-grddl-wg <public-grddl-wg@w3.org>

Note that I was thinking of the "link-extension" since it appears that
"link-extension = token [ "=" ( token | quoted-string ) ]" in RFC 2068.
RFC 2068 is not very clear on where link extensions are - if they are,
as I interpreted it, open season for all sorts of things or if they have
a link-extension registry as you seem to suggestion.

However, I do think the position crafted by the SemWeb-CG is the best
[1] as it is for design and aesthetic reasons much better to use a
separate profile header.

[1]http://lists.w3.org/Archives/Public/public-grddl-wg/2007Feb/0061.html

Dan Connolly wrote:
> Harry,
>
> I gather you're exploring GRDDL link design options that
> use only the already-registered Link: header field.
>
> This won't work:
>
> Link: <http://www.w3.org/2000/06/dc-extract/dc-extract.xsl>;
>   rel="transformation";
>   profile="http://www.w3.org/2003/g/data-view"
>
> The BNF in for Link[iana] doesn't have a profile param:
>           Link           = "Link" ":" #("<" URI ">" *( ";" link-param )
>
>           link-param     = ( ( "rel" "=" relationship )
>                              | ( "rev" "=" relationship )
>                              | ( "title" "=" quoted-string )
>                              | ( "anchor" "=" <"> URI <"> )
>                              | ( link-extension ) )
>
> The "profile" term could match link-extension, but then we're back
> to asking the IETF/IESG for an extension, and the Profile: header
> proposal[mnot] is more mature than anything we'd make up now.
>
> So I don't recommend re-opening the design discussion.
>
> [mnot]
> http://www.mnot.net/drafts/draft-nottingham-http-link-header-00.txt
>
> [iana] http://www.faqs.org/rfcs/rfc2068.html
> which is cited from section 2.1.62.  Header field: Link of
> HTTP Header Field Registrations December 2005
> http://www.rfc-editor.org/rfc/rfc4229.txt
> which is the reference for Link in the permanent
> header registry.
> http://www.iana.org/assignments/message-headers/perm-headers.html
> which was established by IETF consensus recorded in
> Registration Procedures for Message Header Fields September 2004
> http://www.rfc-editor.org/rfc/rfc3864.txt
>
>   


-- 
		-harry

Harry Halpin,  University of Edinburgh 
http://www.ibiblio.org/hhalpin 6B522426
Received on Friday, 9 February 2007 18:06:26 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Tuesday, 8 January 2008 14:11:47 GMT