Re: [xml] Problem with XML Query

["nonlandi" <nonlandi gmx at>]

Hello!

After we researched our problem with the XML namespaces, we came to a very
tricky part in your code.

we are using the function tree.c::xmlReconciliateNs()

Sample:

input:

<?xml version="1.0" encoding="UTF-8"?>
<soapenv:Envelope
xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/";>
        <soapenv:Body>
                <ns0:OBJECT xmlns="urn:schemas-hello-com"
xmlns:ns0="urn:schemas-hello-com" ns0:myValue="12345"/>
        </soapenv:Body>
</soapenv:Envelope>

current output:

<?xml version="1.0" encoding="UTF-8"?>
<soapenv:Envelope
xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/";>
        <soapenv:Body>
                <OBJECT xmlns="urn:schemas-hello-com"
xmlns:ns0="urn:schemas-hello-com" myValue="12345"/>
        </soapenv:Body>
</soapenv:Envelope>

bug ? shouldn't it be ?:

<?xml version="1.0" encoding="UTF-8"?>
<soapenv:Envelope
xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/";>
        <soapenv:Body>
                <OBJECT xmlns="urn:schemas-hello-com"
xmlns:ns0="urn:schemas-hello-com" ns0:myValue="12345"/>
        </soapenv:Body>
</soapenv:Envelope>

problem:

after attribute myValue loses its NS prefix, the semantic of the XML
changes.

we think, that this is comming from here

                for (i = 0;i < nbCache;i++) {
                    if (oldNs[i] == attr->ns) ) {
                     attr->ns = newNs[i];
                     break;
                    }

but we have no clue how to fix this.


Regards
nonlandi

-----Ursprüngliche Nachricht-----
Von: Daniel Veillard [mailto:veillard redhat com] 
Gesendet: Montag, 28. April 2008 16:24
An: Martin Landl
Cc: xml gnome org
Betreff: Re: [xml] Problem with XML Query

On Mon, Apr 28, 2008 at 03:47:06PM +0200, Martin Landl wrote:
> Hi!
>
> I've got a problem with the following XML
> <OBJECT xmlns="http://somenamespace"; xmlns:ns0="http://somenamespace";
myAttribute="myAttributeValue">
>       <STRING xmlns="http://somenamespace";
xmlns:ns1="http://somenamespace";
reference="COOSYSTEM 1 1:objname">stringvalue1</STRING>
>       <STRING xmlns="http://somenamespace";
xmlns:ns2="http://somenamespace";
reference="COOSYSTEM 1 1:objsubject">stringvalue2</STRING>
> </OBJECT>
>
> When I try to query the XPath "/ns1:OBJECT/@ns1:myAttribute" (having
"http://somenamespace"; added as "ns1") added the query returns no nodes.

  and that's normal. default namespace does not apply to attrbutes.
The spec isn't that long, worth spending an hour or so reading it, really
as it's rather important. See section 6.2 it defines it only for elements.
I't confirmed in 6.3 
 "However, each of the following is legal, the second because the default
namespace does not apply to attribute names:"

   http://www.w3.org/TR/REC-xml-names/

> If I change the XML "myAttribute" to "ns0:myAttribute", the same XPath
query returns the attribute node properly.

  yes, that's normal.

Daniel

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