XML::Simple: list all element attributes

element22 has asked for the wisdom of the Perl Monks concerning the following question:

I have a simple XML file:

<?xml version="1.0" encoding="Windows-1252"?>
<App>
<node name="1st node" text="Text of 1st node" />
<node name="2nd node" text="Text of 2nd node" />
<node name="3rd node" text="Text of 3rd node" />
...
</App>
[download]

I want to use XML::Simple to list all the "nodes" and their "text" attributes as follows:

1st node: Text of 1st node
2nd node: Text of 2nd node
3rd node: Text of 3rd node
...
[download]

What I have doesn't work, I get no listing at all:

use XML::Simple;
use Data::Dumper;

my $input="app.xml";

my $xml = new XML::Simple(KeyAttr =>1,ForceArray =>1);
my $data = $xml->XMLin($input);

foreach my $node (@{$data->{App}{node}}) {
    print $node->{name}.": ".$node->{text}."\n";
}
[download]

Comment on XML::Simple: list all element attributes Select or Download Code

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Re: XML::Simple: list all element attributes by frozenwithjoy (Priest) on Apr 08, 2015 at 06:03 UTC
When I add this: `use Data::Printer; p $data;` [download] I get this out: `\ { node [ [0] { name "1st node", text "Text of 1st node" }, [1] { name "2nd node", text "Text of 2nd node" }, [2] { name "3rd node", text "Text of 3rd node" } ] }` [download] There is no key called 'App', so your `@{$data->{App}{node}}` is an empty list. If I change your for loop to this: `foreach my $node (@{$data->{node}}) { print $node->{name}.": ".$node->{text}."\n"; }` [download] I get what you were expecting: `1st node: Text of 1st node 2nd node: Text of 2nd node 3rd node: Text of 3rd node` [download] If you want to keep the root key, you can use the following and keep your original loop. `my $xml = XML::Simple->new( KeyAttr => 1, ForceArray => 0, KeepRoot => + 1 );` [download]	[reply] [d/l] [select]
Re^2: XML::Simple: list all element attributes by element22 (Novice) on Apr 08, 2015 at 06:32 UTC
Thanks, it works now. A quick follow-up question. I've just noticed that a few "nodes" have child "nodes" with similar attributes: `<?xml version="1.0" encoding="Windows-1252"?> <App> <node name="1st node" text="Text of 1st node" /> <node name="2nd node" text="Text of 2nd node"> <node name="subnode A" text="Text of subnode A" /> <node name="subnode B" text="Text of subnode B" /> </node> <node name="3rd node" text="Text of 3rd node" /> ... </App>` [download] I'd like to print this out as follows: `1st node: Text of 1st node 2nd node: Text of 2nd node subnode A: Text of subnode A subnode B: Text of subnode B 3rd node: Text of 3rd node` [download] Without getting into any scary recursion, how would I modify the loop to print out the subnodes, too? `foreach my $node (@{$data->{node}}) { print $node->{name}.": ".$node->{text}."\n"; if ( ... ) { # detect the existence of a subnode here somehow foreach my $subnode (@{$data->{node}{subnode}}) { print "\t".$subnode->{name}.": ".$subnode->{text}."\n"; } } }` [download]	[reply] [d/l] [select]
Re^3: XML::Simple: list all element attributes by frozenwithjoy (Priest) on Apr 08, 2015 at 07:50 UTC
What you are looking for is: `if ( $node->{node} )` However, is a little recursion OK? `print_nodes($data); sub print_nodes { my $data = shift; foreach my $node ( @{ $data->{node} } ) { print $node->{name} . ": " . $node->{text} . "\n"; if ( $node->{node} ) { print_nodes($node); } } }` [download] This should work regardless of how deep the nodes go; however, it doesn't indent: `1st node: Text of 1st node 2nd node: Text of 2nd node subnode A: Text of subnode A subnode B: Text of subnode B 3rd node: Text of 3rd node` [download] EDITED TO ADD INDENTATION: `print_nodes( $data, 0 ); sub print_nodes { my ( $data, $depth ) = @_; my $tab_width = 4; foreach my $node ( @{ $data->{node} } ) { my $indent = " " x $depth x $tab_width; print $indent . $node->{name} . ": " . $node->{text} . "\n"; if ( $node->{node} ) { print_nodes( $node, $depth + 1 ); } } }` [download] `1st node: Text of 1st node 2nd node: Text of 2nd node subnode A: Text of subnode A subnode B: Text of subnode B 3rd node: Text of 3rd node` [download]	[reply] [d/l] [select]
Re^4: XML::Simple: list all element attributes by element22 (Novice) on Apr 08, 2015 at 10:41 UTC
Re: XML::Simple: list all element attributes by choroba (Cardinal) on Apr 08, 2015 at 08:20 UTC
Using XML::XSH2, a wrapper around XML::LibXML: `open file.xml ; for //node { $depth = count(ancestor::*) - 1 ; echo :s { ' ' x $depth } @name ': ' @text ; }` [download] لսႽ† ᥲᥒ⚪⟊Ⴙᘓᖇ Ꮅᘓᖇ⎱ Ⴙᥲ𝇋ƙᘓᖇ	[reply] [d/l]