Re: [apps-discuss] [link-relations] Fwd: I-D Action: draft-ohye-canonical-link-relation-00.txt

Frank Ellermann <hmdmhdfmhdjmzdtjmzdtzktdkztdjz@gmail.com> Sat, 02 July 2011 18:58 UTC

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From: Frank Ellermann <hmdmhdfmhdjmzdtjmzdtzktdkztdjz@gmail.com>
Date: Sat, 2 Jul 2011 20:58:12 +0200
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To: Julian Reschke <julian.reschke@gmx.de>
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Cc: IETF Apps Discuss <apps-discuss@ietf.org>
Subject: Re: [apps-discuss] [link-relations] Fwd: I-D Action: draft-ohye-canonical-link-relation-00.txt
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On 1 July 2011 15:38, Julian Reschke wrote:

>> A relative canonical URL can't be a good idea.  If there is more than
>> one "content URL" (in the terminology of the draft) this would result
>> in more than one canonical URL, defeat the purpose, and worse, this
>> could make googlebot angry.
[...]
> I don't understand (yet).

> What do you mean by "more than one "content URL""?

The rel="canonical" business is for in essence identical content
available at more than one URL.  Simple example, resource xyzzy.html
at http://example.com/xyzzy.hmtl and http://example.org/xyzzy.html

With a relative rel="canonical" URI in xyzzy.html I'd end up with two
different canonical URLs, but then I shouldn't use rel="canonical" in
the first place.

The idea is to get one canonical URL for all (here: both) incarnations
of xyzyy.html.  Well, that's what I meant.  But now I see that relative
can be perfectly fine if and only if all incarnations exist on the same
server, e.g., http://example/xyzzy.html?any-query could get a relative
canonical URL xyzzy.html?default or similar.  A better example in the
draft explaining when a relative canonical URL is okay could help.

-Frank