How do I get a list in a perl hash generated from an XML?

PV66 has asked for the wisdom of the Perl Monks concerning the following question:

Hi Community, Really hoping to get some perl-wisdom on this one, its my second day working on Perl today, and I'm just stuck with an issue that I can't seem to figure out.

Basically I have an XML

<root>
  <ref name="abc_sia_%version1.ref%">
    <func envname = "test01" objectdir = "/home/pv66" 
     base="default_771"/>
  </ref>
</root>
[download]

I want to get the ref name's value, that is "abc_sia_%version1.ref%" as my hash key and the corresponding elements of the tag in a list. So I used Simple XML's function

my $xml = new XML::Simple;
my $data = $xml->XMLin("/home/pv66", ForceArray => 1, KeyAttr => { ref
+ => "name"});
print Dumper ($data);
[download]

But this gives me

$VAR1 = {
         'ref' => 
{
 'abc_sia_%version1.ref' => 
{
 'func' => [
            {
             'envname' => 'test01',
             'objectdir' => '/home/pv66',
             'base' => 'default_771'
            }
           ]       
}                  
};
[download]

And this extra level of hierarchy (after ref) is undesired. I've read at some places that XML::Simple is not the preferred module, and XMLLib should be used, but I couldn't find any resources that drew a parallel to the ForceArray attribute of the XML in method. The desired hash should be:

$VAR1 = {

 'abc_sia_%version1.ref' => 
{
 'func' => [
            {
             'envname' => 'test01',
             'objectdir' => '/home/pv66',
             'base' => 'default_771'
            }
           ]       
}                  
};
[download]

Any help pertaining to this would be appreciated.

Comment on How do I get a list in a perl hash generated from an XML? Select or Download Code

Replies are listed 'Best First'.
Re: How do I get a list in a perl hash generated from an XML? by choroba (Cardinal) on Apr 19, 2021 at 09:53 UTC
Here's how to get the requested structure using XML::LibXML. `#! /usr/bin/perl use warnings; use strict; use XML::LibXML; my $dom = 'XML::LibXML'->load_xml(location => shift); my %struct; for my $ref ($dom->findnodes('/root/ref')) { for my $child ($ref->findnodes('')) { push @{ $struct{ $ref->{name} }{ $child->nodeName } }, { map { $_->nodeName => $_->value } $child->findnodes('@ +') }; } } use Data::Dumper; print Dumper \%struct;` [download] But converting from XML::Simple to XML::LibXML usually changes the code much more. You can extract only the information you need from the XML, so you don't need to build the whole structure at all. `map{substr$_->[0],$_->[1]\|\|0,1}[\\|\|{},3],[[]],[ref qr-1,-,-1],[{}],[sub{}^ARGV,3]`	[reply] [d/l] [select]
Re^2: How do I get a list in a perl hash generated from an XML? by PV66 (Novice) on Apr 19, 2021 at 12:19 UTC
This does make sense @choroba. Out of curiosity, what if my XML had more tags, for example if it looked like: `<root> <config> <build host="https://cpzdomain.local"/> </config> <ref name="abc_sia_%version1.ref%"> <func envname = "test01" objectdir = "/home/pv66" base="default_771"/> </ref> </root>` [download] And I wanted to just make a hash as in my question for only the elements in the <ref> tag, is there anyway to do it with the XML::Simple module?	[reply] [d/l]
Re^3: How do I get a list in a perl hash generated from an XML? by choroba (Cardinal) on Apr 20, 2021 at 11:46 UTC
I can't help you with XML::Simple (and I don't want to). If you need advice to migrate the whole logic to XML::LibXML , though, I can be your consultant. `map{substr$_->[0],$_->[1]\|\|0,1}[\\|\|{},3],[[]],[ref qr-1,-,-1],[{}],[sub{}^ARGV,3]`	[reply] [d/l]
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Re: How do I get a list in a perl hash generated from an XML? by AnomalousMonk (Archbishop) on Apr 19, 2021 at 09:15 UTC
If you're determined to disregard the sound advice against the use of XML::Simple, you can do `Win8 Strawberry 5.8.9.5 (32) Mon 04/19/2021 5:08:21 C:\@Work\Perl\monks >perl -Mstrict -Mwarnings use Data::Dumper; my $got_data = { 'ref' => { 'abc_sia_%version1.ref' => { 'func' => [ { 'envname' => 'test01', 'objectdir' => '/home/pv66', 'base' => 'default_771' } ] } } }; my $want_data = $got_data->{'ref'}; print Dumper $want_data; ^Z $VAR1 = { 'abc_sia_%version1.ref' => { 'func' => [ { 'base' => 'defaul +t_771', 'objectdir' => '/ +home/pv66', 'envname' => 'tes +t01' } ] } };` [download] It looks like the hash reference you want is just the value of the `'ref'` key. See also perldsc. Give a man a fish: `<%-{-{-{-<`	[reply] [d/l] [select]
Re^2: How do I get a list in a perl hash generated from an XML? by PV66 (Novice) on Apr 19, 2021 at 09:46 UTC
Thanks a lot!!!! This did resolve the issue for which I've been scratching my head for so long and it did turn out to be a very efficient, and yeah I'm okay with using XML::Simple in this case :P	[reply]
Re: How do I get a list in a perl hash generated from an XML? by haukex (Archbishop) on Apr 20, 2021 at 05:56 UTC
I very strongly recommend against XML::Simple! A good replacement for reading XML is XML::Rules, its output is much more customizable. Update: If you want `func` to be an arrayref, just replace `'as is'` by `'as array'`. use warnings; use strict; use XML::Rules; use Data::Dump; my $parser = XML::Rules->new( stripspaces => 3\|4, rules => [ root=>'pass', config=>'', build=>'', ref=>'by name', func=>'as is', _default => sub { die "Unknown tag $_[0]" } ] ); my $data = $parser->parse(<<'END_XML'); <root> <config> <build host="https://cpzdomain.local"/> </config> <ref name="abc_sia_%version1.ref%"> <func envname = "test01" objectdir = "/home/pv66" base="default_771"/> </ref> </root> END_XML dd $data; __END__ { "abc_sia_%version1.ref%" => { func => { base => "default_771", envname => "test01", objectdir => "/home/pv66" }, }, } [download]	[reply] [d/l] [select]
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