How do I get LibXML to replace attribute values?

alanpdx has asked for the wisdom of the Perl Monks concerning the following question:

I have a chunk of xml code with a bunch of elements in it. I need to replace some of the data in the xml with some other values. I can make XML::Simple do this, but it mangles the order. I am now trying to get XML::LibXML to work, but I am having a great deal of trouble.

The part of the xml I am wanting to change looks like this:

<remote name="korg">
[download]

I need to be able to change the 'korg' value to something else without totally making a hash out of the document.

What I have tried looks like:

   my $parser = XML::LibXML->new();
   my $doc    = $parser->parse_file($filename);
   my $root = $doc->getDocumentElement;
   print $doc->toString;
   my $query1 = '//remote[@name="korg"]/';
   my ($node1)  = $doc->findnodes($query1);
   $node1->setData('other');
[download]

This was pulled from a XML::LibXML sample. unfortunatly the sample errors out saying it cannot find the function setData in XML::LibXML::Element.

Any ideas how to make this work? I am not a total Perl newbie, but I am a total XPath newbie.

Thanks!

Comment on How do I get LibXML to replace attribute values? Select or Download Code

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Re: How do I get LibXML to replace attribute values? by ikegami (Patriarch) on Apr 20, 2011 at 22:55 UTC
Get the element, and set its attribute: `my ($node) = $doc->findnodes('//remote[@name="korg"]'); $node->setAttribute(name => 'other');` [download] Or get the attribute, and change its value: `my ($node) = $doc->findnodes('//remote/@name[.="korg"]'); $node->setValue('other');` [download] Three key concepts: Everything in the tree is a node, including attributes. The square brackets are like a WHERE clause in SQL. The filter which nodes to return. "." refers to the topic node. In square brackets, that's the node being tested by the square brackets.	[reply] [d/l] [select]
Re: How do I get LibXML to replace attribute values? by Anonymous Monk on Apr 20, 2011 at 22:49 UTC
Your xpath query should be `'//remote[@name="korg"]'`. And use setAttribute() to change the value of the attribute; `my $query = '//remote[@name="korg"]'; $doc->findnodes($query)->shift()->setAttribute('name', 'other');` [download]	[reply] [d/l] [select]
Re: How do I get LibXML to replace attribute values? by choroba (Cardinal) on Apr 21, 2011 at 13:23 UTC
I'd use XML::XSH2: `open file.xml ; for //remote/@name[.="korg"] set . "other" ;` [download]	[reply] [d/l]