W3C home > Mailing lists > Public > public-html@w3.org > April 2010

Re: change proposal for issue-86, was: ISSUE-86 - atom-id-stability - Chairs Solicit Proposals

From: Edward O'Connor <hober0@gmail.com>
Date: Thu, 15 Apr 2010 09:43:57 -0700
Message-ID: <t2x3b31caf91004150943tbbf0e4e2ja9ab2be118bfba32@mail.gmail.com>
To: Sam Ruby <rubys@intertwingly.net>
Cc: Ian Hickson <ian@hixie.ch>, Julian Reschke <julian.reschke@gmx.de>, "public-html@w3.org WG" <public-html@w3.org>
Sam wrote:
> I think that there is a hidden assumption in there some place, but I'm
> not sure. Perhaps something along the lines of "all conforming HTML
> pages should be able to produce something resembling an Atom feed
> using the algorithm specified in section 5.5.3"[...]

I think there is an underlying design principle: Handle Errors[1]. Just
as the HTML parsing algorithm generates a DOM from any input, the
HTML->Atom conversion algorithm generates an Atom feed from any HTML
document (that has <article> elements, see Step 1 of the algoritm[2]).

Julian wrote:
> Either you store the ID with the item, or you derive the ID from something
> sufficiently unique in the set of items, or ... you don't produce an Atom
> feed.

Sam wrote:
> One possible way to address this is for section 5.5.3, step 15, substep 9,
> otherwise clause be modified to throw an INVALID_STATE_ERR exception if it
> is not possible to generate an entry id in a way that ensures uniqueness.

Suppose there's an HTML document with several <article>s, only one of
which triggers the "otherwise" clause of step 15, substep 9. Instead of
throwing an exception and aborting--not producing any feed at all--why
not just leave out that one problematic <atom:entry> from the resulting
feed? So instead of "or ... you don't produce an Atom feed," we don't
produce an Atom *entry* for that specific <article>.

Sam wrote:
> I do believe that the following are all true:
>
> 1) it is the case that some HTML pages can be processed in such a
>    way as to produce a useful Atom feed.
> 2) some people find ability this desirable
> 3) entry ids that are not created in a way that ensures uniqueness
>    not only is technically violated the spec, but are generally
>    problematic
> 4) many who implement the algorithm currently in the spec have no
>    interest or ability to manage state

Agreed on all four counts.


Ted

1. http://www.w3.org/TR/html-design-principles/#handle-errors
2. http://www.whatwg.org/specs/web-apps/current-work/multipage/converting-html-to-other-formats.html#atom
Received on Thursday, 15 April 2010 16:44:49 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Wednesday, 9 May 2012 00:17:07 GMT