On Jan 9, 2010, at 6:30 AM, Arthur Barstow wrote:
Hixie, All,
On Jan 9, 2010, at 3:00 AM, ext Ian Hickson wrote:
Would this working group be interested in adopting the
Window.postMessage
and MessageChannel/MessagePort features from HTML5? It was recently
split
from the main HTML5 spec into a subspec, but some people have
suggested it
might be best in the webapps group. I'd be happy to continue
editing it,
it would just mean a change in the headers, as with Web Storage,
etc (and
would similarly remain in the WHATWG "complete" spec).
Why is this functionality being removed from HTML5?
Some Working Group members requested that it be split into a separate
spec. The reasons cited were that this functionality is not directly
related to HTML5, and that it is potentially reusable with other
languages. In that respect, it is much like Web Workers, Web Sockets,
or Web Storage.
I would also like to understand: the status of the specification
maturity, in particular, its closeness to being ready for LCWD; and
the spec's implementation status.
I believe postMessage (cross-document-messaging) is implemented and
shipping in every major browser. I am not sure about channel
messaging. MessageChannel is implemented and shipping at least in
WebKit (both Safari and Chrome) but I am not sure about other browser
engines.
Additionally, I don't see a direct connection to any of WebApps'
current deliverables although I'm not familiar with this
functionality:
http://www.w3.org/2008/webapps/charter/#deliverables
What this functionality allows is communication among frames, windows
and workers, including possibly ones from separate domains. It enables
cross-domain APIs similar to what you can do with XHR2, but without
any network traffic. It also enables widgets/gadgets embedded in a Web
page to communicate with their containing page. And it is a critical
dependency for Web Workers. You are correct that neither cross-
document messaging or channel messaging is explicitly called out as a
deliverable, but it does seem to bear a close relationship to other
Web Apps specs that used to be part of HTML5.
Is the HTML WG not interested in owning this new "subspec"?
I don't believe the HTML WG has rejected it, but some participants
thought the Web Apps WG should get first crack at it, since it seems
very related to other Web Apps WG deliverables and is not HTML-specific.
Regards,
Maciej
