- From: Petteri Stenius <Petteri.Stenius@remtec.fi>
- Date: Wed, 14 Jun 2000 09:49:19 +0300
- To: "'David Blondeau'" <blondeau@intalio.com>, "'John Boyer'" <jboyer@PureEdge.com>, Joseph Reagle <reagle@w3.org>
- Cc: XML DSig <w3c-ietf-xmldsig@w3.org>
I need to read the attributes of a element anyway, and I also need to sort them using the attribute name and the namespace uri as sort keys. This is the minimum requirement in all cases. What I would like to avoid is walking the parent elements of a node looking for inherited namespace declarations. Petteri > -----Original Message----- > From: David Blondeau [mailto:blondeau@intalio.com] > Sent: Monday, June 12, 2000 9:38 PM > To: Petteri Stenius; 'John Boyer'; Joseph Reagle > Cc: XML DSig > Subject: Re: Updated c14n Spec > > > Hi Petteri, > > > The current XPath canonicalization is starting to look quite nice. > I agree except the optional XPath expression that in my > opinion prevent > non-XPath implementation. > > > My main motivation is performance: the namespace axis > approach requires > one > > to walk the parent nodes of a element when canonicalizing > and keep track > of > > inherited namespaces etc., the old C14N spec is very simple > to implement > in > > one single pass. > [move this part] > > The idea is that an element always declares only those > namespaces that > > appear on the element itself and on the element's attributes. > [end moved part] > If your main motivation is performance, I am not sure your > suggestion is > good since you will need to parse all attribute values to know if a > namespace prefix is used in them -> difficult and time consumig! > The namespace axis is the best approach in my opinion. > > >Other motivations are that the original C14N approach (even without > >namespace rewriting) is simpler to implement and that many > XML processors > do > >not implement the namespace axis functionality. > IMO, the namespace axis functionality is really simple to > implement using > SAX, maybe more complex in DOM, but the attribute values > parsing is really > not a good option. > > David >
Received on Wednesday, 14 June 2000 02:49:10 UTC