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perlxml-simple

Using XML::Simple for retrieving data in Perl

I've created the below XML file for retrieving data.

Input:

<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<ExecutionLogs>
    <category cname='Condition1' cid='T1'>
        <log>value1</log>
        <log>value2</log>
        <log>value3</log>
    </category>
    <category cname='Condition2' cid='T2'>
        <log>value4</log>
        <log>value5</log>
        <log>value6</log>
    </category>
        <category cname='Condition3' cid='T3'>
        <log>value7</log>
    </category>
</ExecutionLogs>

I want the output like below,

Condition1 -> value1,value2,value3
Condition2 -> value4,value5,value6
Condition3 -> value7

I have tried the code below,

use strict;
use XML::Simple;
my $filename = "input.xml";
$config = XML::Simple->new();
$config = XMLin($filename);
@values = @{$config->{'category'}{'log'}};

Please help me on this. Thanks in advance.

Solution

  • What I would do :

    use strict; use warnings;
use XML::Simple;
my $config = XML::Simple->new();
$config = XMLin($filename, ForceArray => [ 'log' ]);
#   we want an array here  ^---------------------^ 

my @category = @{ $config->{'category'} };
#              ^------------------------^
# de-reference of an ARRAY ref  

foreach my $hash (@category) {
    print $hash->{cname}, ' -> ', join(",", @{ $hash->{log} }), "\n";
}

    OUTPUT

    Condition1 -> value1,value2,value3
Condition2 -> value4,value5,value6
Condition3 -> value7

    NOTE

    ForceArray => [ 'log' ] is there to ensure treating same types in {category}->[@]->{log] unless that, we try to dereferencing an ARRAY ref on a string for the last "Condition3".

    Check XML::Simple#ForceArray

    and