Re: [XPath Filter 2.0] Problem with Transform model
Christian Geuer-Pollmann <[email protected]> Mon, 27 May 2002 11:12:36 +0200
| Newsgroups | gmane.ietf.xmldsig |
|---|---|
| Message-ID | <953921.1022497956@pinkpanther> |
Hi Gregor, --On Sonntag, 26. Mai 2002 14:31 +0200 Gregor Karlinger <[email protected]> wrote: > after I implemented the current spec of XPath Filter 2.0[1], I > started to play around with some akward combinations of input > node set (I) and expanded evaluated XPath expression (S) and > came across the following problem: > > If the transform implementation receives an empty input node set > as its input paramter, there is no way to get access to the > input document. But this is necessary because the context > node for the XPath transform has to be initialized with the > root node of the input document (according to section 3.3 > of [1]). Absolutely right. If you don't have at least one node which works as an "anchor" into the to-be-signed document, you can't proceed (well, it'd be possible to create nasty hacks which do not only pass the node set information to the transform but also the owner document). > A possible solution for this problem could be to explicitely > forbid an emtpy input for the XPath Filter 2.0 transform. Any > thought? For me, +1. That'd be a good addition/clarification to the spec. Empty node sets should be an error. Regards, Christian