New XPath Filter Transform

John has done a great job of quickly putting together a new XPath Signature 
filter spec. I've done some tweaks and posted it at [1]. Below I list some 
of my tweaks that John (or anyone else) can push back on.

1. As we did for exc-c14n, I've assigned it a tenative namespace instead of 
using the actual documents URI:

2. I added a schema and DTD for the instance syntax, and in the process 
ended up moving from John's

  <SignatureFilter FilterType="include" xmlns:dsig="&dsig;">


   <XPath Filter="include"

because the schema based on the original syntax had a FilterType attribute 
in the SignatureFilterType complexType -- it started looking confusing. 
Also, in the end I felt that using syntax similar to the existing XPath 
transform, and just considering this 2.0 made things easier to understand 
3. John originally had the "exclusive" be default. However, I wasn't sure 
if this was supposed to be implicit processing behaviour (which we try to 
avoid) or in the schema (we also try to avoid defaults there). So in the 
interest of explicitness I made it required to specify.

Thoughts? (On these syntax issues, or implementation performance)


Joseph Reagle Jr.       
W3C Policy Analyst      
IETF/W3C XML-Signature Co-Chair
W3C XML Encryption Chair

Received on Thursday, 7 February 2002 17:47:38 UTC