Re: Collections of web pages

Thinking about this a bit more, I think that we can make the case that an EPUB is a web page under the current definition, so we can handle this in Understanding.

I think that it is fairly straightforward to make the case that an EPUB is a Web page. The definition of web page already provides for resources that are used in the rendering (e.g. a TOC document, files for different chapters) and they are certainly intended to be rendered together by a user agent:

Web page
a non-embedded resource obtained from a single URI using HTTP plus any other resources that are used in the rendering or intended to be rendered together with it by a user agent<https://www.w3.org/TR/WCAG21/#dfn-user-agents>

A Set of Web Pages hinges on this definition:
set of web pages
collection of web pages<https://www.w3.org/TR/WCAG21/#dfn-web-page-s> that share a common purpose and that are created by the same author, group or organization

The key difference is the fact that where there are pages that are used in the rendering of the overall resource, those are part of the “page” that is the main resource. The same applies to a web page that has an iframe where another page is rendered – we don’t evaluate that iframe-contained page as its own separate entity unless it is also viewed separately.

My analysis of the impact of this on evaluating EPUB under some key SC:

If an EPUB is a single web page:
2.4.1 Bypass blocks: Doesn’t apply. The risk is that a user might encounter navigation content that appears on every “screen” or “view” that the user encounters when navigating the EPUB content and not have a way to easily bypass it.
2.4.2 Page Titled: Applies and the “main” page title would only fail if the title didn’t reflect the publication title.
2.4.5 Multiple Ways: Doesn’t apply. The risk is that users might only have one way to locate content in the EPUB. This is not an issue for an EPUB that has a TOC.
3.2.3 Consistent Navigation: Doesn’t apply. Navigations mechanisms could appear in a different relative order, although this is unlikely for an EPUB.
3.2.4 Consistent Identification: Doesn’t apply. Components that have the same purpose throughout the EPUB (e.g. if each EPUB chapter had a “next chapter” arrow icon button with a slightly different name that wouldn’t fail this SC).

If an EPUB is a set of web pages:
2.4.1 Bypass blocks: 2.4.1 applies and content that is repeated on multiple pages needs to have a mechanism to be skipped.
2.4.2 Page Titled: Applies and each page (e.g. “War and Peace, Chapter 2”) would need to be set.
2.4.5 Multiple Ways: 2.4.5 applies and more than one mechanism is needed to locate pages within the set.
3.2.3 Consistent Navigation: 3.2.3 applies and requires that navigation mechanisms that are repeated appear in the same relative order.
3.2.4 Consistent Identification: 3.2.4 applies and requires consistent names are used for components with the same functionality.



Thanks,
AWK

Andrew Kirkpatrick
Head of Accessibility
Adobe

akirkpat@adobe.com
http://twitter.com/awkawk


From: Matt Garrish <matt.garrish@gmail.com>
Date: Tuesday, April 14, 2020 at 7:34 AM
To: Alastair Campbell <acampbell@nomensa.com>, WCAG <w3c-wai-gl@w3.org>
Cc: 'Avneesh Singh' <avneesh.sg@gmail.com>
Subject: RE: Collections of web pages
Resent-From: WCAG <w3c-wai-gl@w3.org>
Resent-Date: Tuesday, April 14, 2020 at 7:33 AM

> ‘Set of web pages’ can apply to a sub-domain with a shared navigation. ePub is more constrained than that, so it does appear to be a sub-set of the current definition that also applies to a web page.

That makes sense to me after reading David’s reply. Having lived almost forever in publishing, I didn’t realize that set of web pages was intended for as loose a concept as a site. I was thinking more an app with a specific progression, or sequence of pages. It would be disruptive to use what I offered as a general definition.

> Electronic Publication

Maybe just change this to digital publication, as that’s the name we now typically use. “Electronic” was always a bit of a misnomer.

Matt

From: Alastair Campbell <acampbell@nomensa.com>
Sent: April 14, 2020 06:35
To: WCAG <w3c-wai-gl@w3.org>
Cc: Avneesh Singh <avneesh.sg@gmail.com>; Matt Garrish <matt.garrish@gmail.com>
Subject: RE: Collections of web pages

Hi everyone,

Interesting discussion, ePub being a single & set of pages reminded me of high-school Physics, where light is both a particle and a wave!

Thinking through Peter’s 1st principles approach, and looking at the epub conformance guidance [1], for example:
> it is not sufficient for individual Content Documents to have a logical reading order if the publication presents them in the wrong order. Likewise, including a title for every Content Document is complementary to providing a title for the publication: the overall accessibility is affected if either is missing.

Considering the backwards compatibility, adjusting the scope of ‘set of web pages’ would mean somethings in 2.0/1 would be in scope there, and then out of scope in 2.2 (or vice versa).

How about a separate definition for epub (like) things? If it is essentially a sub-set of ‘set of web pages’, and can be applied (where applicable) to a ’web page’, that’s what we’re aiming for I think?

‘Set of web pages’ can apply to a sub-domain with a shared navigation. ePub is more constrained than that, so it does appear to be a sub-set of the current definition that also applies to a web page.

I’m not sure what to call it, but as a first draft based on Matt’s:
----------------
Electronic Publication
one or more web pages<https://www.w3.org/TR/WCAG21/#dfn-web-page-s> logically connected and with at least one defined reading order, such that whole would be incomplete or unusable if any were unavailable

Note: An electronic publication may be a single web page, or a set of pages.

Note: An electronic publication may be packaged and made available as a single web page (e.g., EPUB), but the packaging does not alter the nature of the publication.
----------------

Then we could include that in the scope of the new SC, and possibly refine a couple of the previous ones if it can be done in a backwards compatible way.

-Alastair

1] http://idpf.org/epub/a11y/#sec-wcag-eval