DPUB IG Telco, 2016-05-23: W3C/IDPF Plans, Web Platform WG

See minutes online for a more detailed record of the discussions. (The headers below link into the relevant sections of the minutes.)

IDPF/W3C Plans

There was an announcement on the exploration of W3C and IDPF joining forces; this was discussed a bit on the call. Nick reported on a mailing list discussion, and the main question there was what the impact would be on publishing. There were some concerns around the messaging, on how these things have been decided, etc. Karen also reported on an article on CNET.

Ivan raised the issue that the current messaging does not emphasize enough the importance of the use case document that the IG is planning, and also emphasizing that the current PWP document is not necessarily a done deal as it is; the use case evolution may modify it greatly. Finally, Dave raised the issue that there were many discussions leading up to the announcement that was done in closed fora, and the final decision process should be made more in the public. The group also wondered about the possibility for further public discussions around this, including a possible Webinar.

Web Platform WG topics

Charles McCathieNeville (“chaals”), co-chair of the Web Platform WG at W3C, was the guest of the call to discuss some areas of common interest.


There is a work item in the WPWG on packaging but, at this moment, there are no real takers. Packaging is obviously of interest for the publishing community, and the question arose whether this community wants to push the current approach. The fact is that most browsers have an extension that uses zip and a manifest; i.e., that approach would get some traction, as opposed to the current proposal.

During the discussion it came to the fore that publishers currently use zip+manifest, although the current formats for manifests, as well as the specificities on zip usage, are not very Web friendly. But there is already work going on (in the IDPF EPUB WG) to update the manifest, a JSON approach, which is the current line at W3C (see the Web App Manifest, is probably o.k. for the Publishing Industry on long term. That being said, it is not clear how the current Web App Manifest can be extended for a particular community.

It has been agreed that the DPUB IG would submit issues or comments on the manifest as well as the packaging work to make its position clear.

Service Workers

The current work on PWP relies on concepts that calls for a tool like Service Workers. Dave has already experimented with this, but questions arose about the longevity of the Service Worker spec, and whether it is really something the community can rely on. It seems that Service Workers are indeed here to say, although the first implementations will probably not be optimal. But it is a safe bet to use them. (See also caniuse entries on it: Mozilla and Chrome already ship it, Microsoft has expressed interest. Not clear about Safari.)

HTML Extensions, Custom Elements (eg, the element)

Lately there were lots of discussion on the re-introduction of the element, that would certainly be of interest for the Publishing Community. What is needed today is to have clear usage data through an implementation. It was emphasized that “implementation” does not necessarily mean one of the browsers; if an EPUB reading system implemented it and used it, this would constitute a good proof of usage.

On a more general level, the issue of HTML Extensions, in particular Custom Elements, came to the fore, as well as the general approach for extensions. For Custom Elements, although it is only supported in Chrome/Opera at this point, the plan is to go ahead and others will also implement it; more generally, the approach using discussions in the HTML Incubator was emphasized as a means to bring new features into HTML.

It was agreed to have these types of meetings with the WPWG more often…