RE: Registration behavior when action attribute is missing

> -----Original Message-----
> From: ext Greg Billock [mailto:gbillock@google.com]
> Sent: Monday, April 16, 2012 7:35 PM
> To: Chan Cathy (Nokia-CIC/Boston)
> Cc: public-web-intents@w3.org
> Subject: Re: Registration behavior when action attribute is missing
> 
> On Mon, Apr 16, 2012 at 1:54 PM,  <Cathy.Chan@nokia.com> wrote:
> > >From the description of registration markup (3.5.1 in [1]):
> > [[
> > action of type string, readonly
> > An opaque string indicating the behavior class the service supports.
> > It is recommended that users use a fully qualified URI. If the action
> > attribute is missing, the intent Service is assumed to handle display
> > of the provided
> > type(s) in the type attributes.
> > ]]
> >
> > What does "assumed to handle display of the provided type(s) in the
> > type attributes" mean in practice?
> 
> Our original thought was that this would basically mean default action is
> "http://webintents.org/view" or whatever synonym means "display the
> information." We're now leaning towards this being a bad idea, and having
> no action will either mean something else entirely (ie. for interoperation
with
> registerProtocolHandler type usage or registerContentHandler usage), or
> would even be state indicating the browser should take no registration
action.
> 
> In short, the intent tag is a bit in flux. If you're reading WhatWG, Ian
Hickson
> has suggested using the intent tag to do declarative indication of
> registerProtocolHandler, registerContentHandler, and web intents handlers.
> We see a lot to like with that approach, so assuming we go that direction,
it'll
> be the authority on the interpretation of the syntax there.
> 
Got it. Sounds reasonable. I'll keep following the WhatWG discussion then.

> (Currently our work in Chromium doesn't support the <intent> tag.)
> 
> > Also, 3.5 states that
> > [[
> > The algorithm for matching intents is that the action string provided
> > in invocation and registration must match exactly, and the type
> > strings must match exactly except for possible [RFC2046] MIME subtype
> wildcards.
> > ]]
> > Given that the action string in invocation can never be empty/missing
> > , the UA will never attempt to dispatch an intent to a service page
> > with a missing action attribute. Wouldn't it be simpler to disallow
> > missing action attribute in the registration markup in the first place
> > (except in the case of unregistering the intent)?
> 
> Short answer is "yes". :-) But the overall syntax may end up meaning that
this
> is legal usage. Here's one possible future direction:
> 
> <intent type="application/x" href="xyz"></intent> could mean "this handler
> (xyz) is registered for registerContentHandler type handling for type
> "application/x".
> 
> It would then probably be legal to trigger this same handler with this
call:
> 
> navigator.startActivity(new Intent({"type":"application/x",
> "data":myX_Blob}));
> 
> That is, not using "action" would give developers an imperative way to
invoke
> registered protocol and content handlers.
> 
> 
> >
> > [1] http://dvcs.w3.org/hg/web-intents/raw-file/tip/spec/Overview.html