Re: [whatwg] Empty html manifest= attribute handling.

2009-08-11 Thread Ian Hickson 
On Fri, 31 Jul 2009, Michael Nordman wrote:
 
 How empty html manifest= attribute values are handled in the section 
 9.2.5.5 may want some massaging.
 
 http://www.whatwg.org/specs/web-apps/current-work/multipage/syntax.html#parser-appcache
 
  If the Document is being loaded as part of navigation of a browsing 
  context, then: if the newly created element has a manifest attribute, 
  then resolve the value of that attribute to an absolute URL, relative 
  to the newly created element, and if that is successful, run 
  the application cache selection algorithm with the resulting absolute 
  URLwith any fragment component removed; otherwise, if there is no 
  such attribute or resolving it fails, run the application cache 
  selection algorithm with no manifest. The algorithm must be passed 
  the Document object.
 
 This ends up passing the value of the document url into the cache 
 selection algorithm as the manifest url, which will initiate an update 
 and all that.

Correct.


 A couple of things that may make sense.
 
 1) equate html manifest= with html treat empty as 
 non-existent.
 
 2) don't resolve the url if the attribute value is empty, pass an empty 
 url to the cache selection algorithm, and have that algorithm flag such 
 resources as foreign if it was loaded from an appcache
 
 Both of these prevent the initiation of an update that is doomed to 
 fail.

I don't see much point in hardcoding defenses against this case. If it 
fails it fails.

-- 
Ian Hickson   U+1047E)\._.,--,'``.fL
http://ln.hixie.ch/   U+263A/,   _.. \   _\  ;`._ ,.
Things that are impossible just take longer.   `._.-(,_..'--(,_..'`-.;.'

[whatwg] Empty html manifest= attribute handling.

2009-07-31 Thread Michael Nordman 
Hello,

How empty html manifest= attribute values are handled in the
section 9.2.5.5 may want some massaging.

http://www.whatwg.org/specs/web-apps/current-work/multipage/syntax.html#parser-appcache

 If the Document is being loaded as part of navigation of a browsing context, 
 then: if the newly
 created element has a manifest attribute, then resolve the value of that 
 attribute to an absolute
 URL, relative to the newly created element, and if that is successful, run 
 the application cache
 selection algorithm with the resulting absolute URLwith 
 any fragment component removed;
 otherwise, if there is no such attribute or resolving it fails, run 
 the application cache selection
 algorithm with no manifest. The algorithm must be passed the Document object.

This ends up passing the value of the document url into the cache
selection algorithm as the manifest url,
which will initiate an update and all that.

A couple of things that may make sense.

1) equate html manifest= with html treat empty as non-existent.

2) don't resolve the url if the attribute value is empty, pass an
empty url to the cache selection algorithm,
and have that algorithm flag such resources as foreign if it was
loaded from an appcache

Both of these prevent the initiation of an update that is doomed to fail.