perlquestion
FreakyGreenLeaky
<p>
Evening robe-rufflers... I have next to zero experience with XML and XML::LibXML and I hope someone can shed some light on the following.</p>
<p>Basically, I want to remove some empty elements in XML.</p>
<code>
<?xml version="1.0" encoding="UTF-8"?>
<epp xmlns="urn:ietf:params:xml:ns:epp-1.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="urn:ietf:params:xml:ns:epp-1.0 epp-1.0.xsd">
<command>
<update>
<contact:update xmlns:contact="urn:ietf:params:xml:ns:contact-1.0" xsi:schemaLocation="urn:ietf:params:xml:ns:contact-1.0 contact-1.0.xsd">
<contact:id>testaccount3</contact:id>
<contact:add/>
<contact:rem/>
</code>
<p>I need to remove those last two empty elements, but I'm guessing the namespace stuff (or something) is a factor.</p>
<p>I've naively tried the following:</p>
<code>
for my $remove ($frame->findnodes(q{/command/update/contact:update/contact:add})) {
$remove->unbindNode;
}
</code>
<p>
<b>Edit:</b> using the above findnodes() results in the error:</p>
<code>XPath error : Undefined namespace prefix
error : xmlXPathCompiledEval: evaluation failed
</code>
But I must admit I'm clueless here and would appreciate some pointers.
<p>
<b>Update:</b><br>
I've been looking at the source which creates the XML:<br>
<code>/usr/lib/perl5/site_perl/5.8.8/Net/EPP/Frame/Command/Update/Contact.pm</code><br><br>
<code>
sub new {
my $package = shift;
my $self = bless($package->SUPER::new('update'), $package);
my $contact = $self->addObject(Net::EPP::Frame::ObjectSpec->spec('contact'));
foreach my $grp (qw(add rem chg)) {
my $el = $self->createElement(sprintf('contact:%s', $grp));
$self->getNode('update')->getChildNodes->shift->appendChild($el);
}
return $self;
}
</code>
And I must confess to being mightily tempted to just remove <code>add rem</code> from the <code>foreach</code>. This works, but it makes me feel decidedly dirty - and I might need those elements in the future.
</p>
<p>
<b>Solution:</b><br>
<code>
my $p = $frame->getElementsByTagName('contact:update');
foreach my $n ($p->[0]->childNodes()) {
$p->[0]->removeChild($n) if $n->toString(1) eq "<contact:add/>";
}
</code>
Not very elegant, but it works. If someone knows of a better way, I'd love to hear it.
</p>