ARIA and DPUB published a First Public Working Draft (FPWD)

By: Tzviya Siegman, Markus Gylling, and Rich Schwerdtfeger

We are excited to announce that a joint task force of the Protocols and Formats Working Group and the Digital Publishing Interest Group (DPUB IG) has published a First Public Working Draft of Digital Publishing WAI-ARIA Module 1.0 (DPUB-ARIA 1.0). This draft represents the joint collaboration of experts in both accessibility and digital publishing, and the vocabulary it contains represents their efforts to bring digital publishing structures to the web in a broadly accessible way.

The DPUB-ARIA 1.0 vocabulary is still very much a work in progress, and we are seeking input on its usability and completeness from a number of communities. As a result of this review, we expect that there will be changes, so we ask you to hold off on implementing the vocabulary until a later release, as there are open issues in the document that will affect its final appearance. Instead, please share your comments, run some trials, and tell us how they go.

The roles listed in DPUB-ARIA 1.0 originated with the EPUB 3 Structural Semantic Vocabulary, a vocabulary for adding inflection to HTML, managed by the International Digital Publishing Forum (IDPF), the authors of the EPUB specification. The IDPF drew its original list of terms from the DAISY Consortium, the originators of the Digital Talking Book format. During the decades that the DAISY Consortium has maintained its standard, much has been learned about how to develop semantically rich content that can be easily read and navigated by anyone with a print disability. This work has influenced and been influenced by the broader work of the digital publishing community, and informed the development of the accessible EPUB 3 format.

DPUB-ARIA 1.0 defines structural semantics, which provide authors and publishers a method of conveying intent and specific meaning to HTML tagging. A digital publishing structural semantics vocabulary defines a set of properties or behaviors relating to specific elements of a publication. This can improve general user experience as well as accessibility to users with disabilities. For example, publications often feature glossaries, which are typically marked up as a definition list using the <dl> element. However, a document may contain many definition lists, only one of which is the glossary. Adding role="glossary" to the appropriate list conveys machine-readable and human-readable information about the type of list. The inflection provided by the role enables readers of all abilities to access the glossary component. A user agent might use the declarative "glossary" markup to generate pop-ups glossary terms as the user encounters the terms while reading. At the same time, the role is exposed to assistive technology (AT), so the information is meaningful to users who cannot access the pop-up.

Books and other publications have some unique properties. Publishing has many moving parts, and the nuances of a publication are not always easy to represent in HTML. For example, a book or journal production workflow relies heavily on identifying each granular element to enable processing and reuse of content. It is important for publishers and their tools to be able to distinguish among the components that are "foreword"s, "preface"s, and "chapter"s. Without these declarations, we must rely on heuristics or attributes like "title", which are useful only when working in a single language. There are several ways inflection can be accomplished. Possibilities include embedding RDFa data or stretching the technical definition of the data-* attribute. We weighed the merits of several methods and concluded that one of the most important aspects is to provide a clear method of communicating with assistive technologies. The obvious solution then is extending WAI-ARIA, which already has ways of exposing roles to these technologies.

DAISY has been creating and facilitating accessible books for years, and the time has come to converge with the accessible web. Bringing these semantics into WAI-ARIA represents the next step in the evolution of digital publishing, making it easier to create rich and accessible HTML, whether the author is a traditional publisher or not. This is therefore also the first implementation of the general WAI-ARIA extension mechanism that allows groups to write extensions to accelerate greater semantic interoperability with assistive technologies while providing semantic curb cuts for the broader Web community. An example might be a new digital book reader's feature that responds to a voice command, "go to the glossary", and immediately navigate to the book's glossary without having to flip pages to get there.

One of the roles of the DPUB IG is to work with technical representatives of the web and publishing communities toward convergence of digital publishing and web standards (see a recent blog on the Digital Publishing Interest Group and its current plans). The DPUB IG includes representatives of the standards organizations of the publishing world, the IDPF and DAISY. Publishers have hundreds of years of experience in creating books, journals, magazines, and other publications. Modern publishing workflows and standards rely heavily on the traditions of publishing as well as on the technologies and specifications of the open web platform. The DPUB IG seeks to offer our input toward improving publishing on the web and leverage the technologies of the Web as we improve publishing. This document is one of the first examples. The DPUB ARIA TF also worked with members of the HTML Accessibility Task Force to agree to a method that is appropriate for all user agents.

Shortly, the DPUB ARIA Task Force will begin the work of creating mappings to assistive technologies. We will also work with the IDPF and other members of the digital publishing community to ensure that everyone is comfortable with this proposed vocabulary. We also want to ensure that the dpub- vocabulary is itself extensible. Indeed, there are many terms in the IDPF's vocabulary that are not yet addressed. For example, the IDPF has been working on specifications for educational publishing, and we know that there is ongoing work to address the accessibility of (educational) assessments.

We publish this draft with some open questions:

• Are the proposed roles clear and appropriate to the needs of digital publishing?
• Is the use of the dpub- prefix in role names to avoid potential collision with other WAI ARIA roles acceptable?
• What mechanism would be suitable for addition of new roles?
• Is the relationship of this specification to WAI ARIA 1.1 clear?

We are eager to receive your comments. If you're interested in contributing to the development of this and similar work, consider joining the DPUB Interest Group or the Protocols and Format Working Group. Please submit issues with the label "dpub". If this is not feasible, please send an email to [email protected].