Finding Data based on attribute help!

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

Hi Monks!
I am trying to get the value inside of the node "<Rule" but only if the atribute action is equal to "Required", I cant get it to work, any ideas how I could have this done using XML::XPath?
Thanks for the help!


#!/usr/bin/perl
use warnings;
use strict;

my $a = do {local $/; <DATA>};

use XML::XPath;
use XML::XPath::XMLParser;
    
    my $xp = XML::XPath->new(xml => $a);
    
     foreach my $cid ($xp->findnodes('/PartyA/com.Info')) 
      { 
        my $code = $cid->find('Rule/@action')->string_value;
        
        print "\n$code\n";        

      }


__DATA__
<?xml version="1.0" encoding="UTF-8"?>
<PartyA>
                    <Real/>
                    <com.Info>
                        <Action>A</Action>
                        <Rule action="Required">TQA</Rule>
                        <Item>
                            <Other>
                                <Type>Key</Type>
                            </Other>
                            <Other>
                                <Type>com.csc_ClientKey</Type>
                                <OtherId>700</OtherId>
                            </Other>
                            <Other>
                                <Type>Sum</Type>
                            </Other>
                        </Item>
                    </com.Info>
                    <Real/>
                    <com.Info>
                        <Action>A</Action>
                        <Rule>YWX</Rule>
                        <Item>
                            <Other>
                                <Type>Key</Type>
                            </Other>
                            <Other>
                                <Type>com.csc_ClientKey</Type>
                                <OtherId>500</OtherId>
                            </Other>
                            <Other>
                                <Type>Sum</Type>
                            </Other>
                        </Item>
                    </com.Info>
                    
</PartyA>
[download]

Comment on Finding Data based on attribute help! Download Code

Replies are listed 'Best First'.
Re: Finding Data based on attribute help! by ikegami (Patriarch) on May 17, 2010 at 15:59 UTC
XPaths are like file system paths. If the last component of a path is a directory, it's a directory path. If the last component of a path is a file, it's a file path. In your case, the last component ("test") is an attribute, so you're selecting an attribute. You could select its parent `Rule/@action="Required"/..` [download] but it's more typical (and flexible) to uses a subquery `Rule[@action="Required"]` [download] If you're familiar with SQL, square brackets are kinda like an SQL WHERE clause.	[reply] [d/l] [select]
Re: Finding Data based on attribute help! by toolic (Bishop) on May 17, 2010 at 15:56 UTC
This prints 'TQA': `print $cid->find('Rule')->string_value, "\n" if $code eq 'Requ +ired';` [download]	[reply] [d/l]