[MOBY-dev] Perl question

[Andreas Groscurth]

Hiho,

because of the awesome perl hackers on the list.. I hope someone can help 
me....

I have the following Moby response

<?xml version="1.0" encoding="UTF-8"?>
<moby:MOBY xmlns:moby="http://www.biomoby.org/moby">
  <moby:mobyContent>
    <moby:mobyData moby:queryID="sip_1_">
      <moby:Collection moby:articleName="pubmedID">
        <moby:Simple>
          <moby:Object moby:id="" moby:namespace="PMID_" />
        </moby:Simple>
        <moby:Simple>
          <moby:Object moby:id="7743940   " moby:namespace="PMID_" />
        </moby:Simple>
        <moby:Simple>
          <moby:Object moby:id="9090879   " moby:namespace="PMID_" />
        </moby:Simple>
        <moby:Simple>
          <moby:Object moby:id="9090880   " moby:namespace="PMID_" />
        </moby:Simple>
      </moby:Collection>
    </moby:mobyData>
  </moby:mobyContent>
</moby:MOBY>

and the following perl code

my $parser = XML::LibXML->new();
$parser->clean_namespaces( 1 );
my $doc = $parser->parse_string($resultXML);
my $root = $doc->getDocumentElement;

my @objectNodes = ();
# $outObjType = Object (!)
@objectNodes = $root->findnodes("//moby:$outObjType");
# deal with 'moby-less' xml tags:
@objectNodes = $root->findnodes("//$outObjType") unless @objectNodes;
my $resCnt = 0; # a result counter, used as default for file naming
# iterate over all result objects
foreach my $objectNode (@objectNodes) {
# create a filename and write the object to the cache directory

# if provider uses other namespaces (that is other
# than the start namespace of the application), get
# this and use it for cache file name
my ($ns,$id);
if ( $objectNode->hasAttributeNS('moby', 'namespace') ) {
     $ns = $objectNode->getAttributeNS('moby', 'namespace');
}
# deal with 'moby-less' attributes
elsif ( $objectNode->hasAttribute('namespace') ) {
  $ns = $objectNode->getAttribute('namespace');
}

as far as I understand this code (is from Dirks aggregator), it should parse 
the namespace of the element 'moby:Object'... but it doesnt.

I know nothing about LibXML and parsing xml in Perl.. so I was wondering, why 

if ( $objectNode->hasAttributeNS('moby', 'namespace') ) {
     $ns = $objectNode->getAttributeNS('moby', 'namespace');
}

is not working.

Any hints ?

Thanks
Andreas