Re^5: XML Parse, Spanish Elements

Hi jbrugger,

To explain the reasong why I am unconfortable with XML::Simple, let me show you an example:

#!/usr/bin/perl

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

my $xml1 =<<"eof";
<config logdir="/var/log/foo/" debugfile="/tmp/foo.debug">
    <server name="sahara" osname="solaris" osversion="2.6">
      <address>10.0.0.101</address>
      <address>10.0.1.101</address>
    </server>
    <server name="gobi" osname="irix" osversion="6.5">
      <address>10.0.0.102</address>
    </server>
    <server name="kalahari" osname="linux" osversion="2.0.34">
      <address>10.0.0.103</address>
      <address>10.0.1.103</address>
    </server>
  </config>
eof

my $xml2 =<<"eof";
<config logdir="/var/log/foo/" debugfile="/tmp/foo.debug">
    <server attr="sahara" osname="solaris" osversion="2.6">
      <address>10.0.0.101</address>
      <address>10.0.1.101</address>
    </server>
    <server attr="gobi" osname="irix" osversion="6.5">
      <address>10.0.0.102</address>
    </server>
    <server attr="kalahari" osname="linux" osversion="2.0.34">
      <address>10.0.0.103</address>
      <address>10.0.1.103</address>
    </server>
  </config>
eof

print "Structure1:\n".Dumper(XMLin($xml1,ForceArray => 1));
print "Structure2:\n".Dumper(XMLin($xml2,ForceArray => 1));
[download]

The two pieces of XML are identical exept that in the first one the attribute name (could also be id) is specified, in the second it is not. The result is a parse structure that is completely different, changing the first element from an array into a hash! This is with ForceArray turned on.

Structure1:
$VAR1 = {
          'debugfile' => '/tmp/foo.debug',
          'server' => {
                      'kalahari' => {
                                    'osversion' => '2.0.34',
                                    'osname' => 'linux',
                                    'address' => [
                                                 '10.0.0.103',
                                                 '10.0.1.103'
                                               ]
                                  },
                      'sahara' => {
                                  'osversion' => '2.6',
                                  'osname' => 'solaris',
                                  'address' => [
                                               '10.0.0.101',
                                               '10.0.1.101'
                                             ]
                                },
                      'gobi' => {
                                'osversion' => '6.5',
                                'osname' => 'irix',
                                'address' => [
                                             '10.0.0.102'
                                           ]
                              }
                    },
          'logdir' => '/var/log/foo/'
        };
Structure2:
$VAR1 = {
          'debugfile' => '/tmp/foo.debug',
          'server' => [
                      {
                        'osversion' => '2.6',
                        'osname' => 'solaris',
                        'address' => [
                                     '10.0.0.101',
                                     '10.0.1.101'
                                   ],
                        'attr' => 'sahara'
                      },
                      {
                        'osversion' => '6.5',
                        'osname' => 'irix',
                        'address' => [
                                     '10.0.0.102'
                                   ],
                        'attr' => 'gobi'
                      },
                      {
                        'osversion' => '2.0.34',
                        'osname' => 'linux',
                        'address' => [
                                     '10.0.0.103',
                                     '10.0.1.103'
                                   ],
                        'attr' => 'kalahari'
                      }
                    ],
          'logdir' => '/var/log/foo/'
        };
[download]

If you look at the semantics of things, why does changing an attribute name (whether it is 'name' or not) change the structure of the resulting parse tree? I find this illogical and prone to making mistakes while parsing an XML file, but maybe that's just me.

--
Cheers,
Rob

Comment on Re^5: XML Parse, Spanish Elements Select or Download Code

Replies are listed 'Best First'.
Re^6: XML Parse, Spanish Elements by jbrugger (Parson) on Feb 13, 2006 at 12:33 UTC
Hmm.... weird, but you are right here... Anyway.. Like others said... well, don't use it :-) "We all agree on the necessity of compromise. We just can't agree on when it's necessary to compromise." - Larry Wall.	[reply]