Generating elements with attributes and contents using XML::Smart

[pfaut]

I am reading data from a database and attempting to create XML using XML::Smart. I'm having some problems creating elements that have attributes and textual content.

I would like to create things along the lines of:

<phone type="home">555-1234</phone>

But I can't quite get it to work. I either lose the attribute altogether or it gets inserted as a tag inside the phone element's contents. It might have been confusing it a little that the 'phone' element was defined with a 'type' attribute and I also had a 'type' element but that had nothing to do with 'phone' element. I tried changing the attribute to 'xxx' but then it never showed up in the output.

As far as I can tell, it's valid XML. Is it possible to create this using XML::Smart with a DTD?

From the DTD:

<!ELEMENT customer (phone+)>
<!ELEMENT phone (#PCDATA)>
<!ATTLIST phone type PCDATA #REQUIRED>

[leriksen]

I dont know the exact form of the (presumably) hash you are getting back form the DB, but here is one way for a fairly flat hash

#!/usr/bin/perl -w

use strict;

use Data::Dumper;

use XML::Simple qw(:strict);

my $data = {
        phone => '555-1234',
        type  => 'home'
       };

print STDERR XML::Simple->new(KeyAttr => {phone => 'type'},
                  RootName => 'phone',
                  XMLDecl => 1,
                  ContentKey => 'phone',
                 )->XMLout($data);

output

/usr/bin/perl -w "/home/le6303/src/perl/phone.pl" 
<?xml version='1.0' standalone='yes'?>
<phone type="home">555-1234</phone>

Update : changed the KeyAttr to the more preferred hash form

[gmpassos]

This will create what you want:

  use XML::Smart ;
  
  my $xml = new XML::Smart() ;
  
  $xml->{phone} = '555-1234' ;
  $xml->{phone}{type} = 'home' ;

  print $xml->data ;

Output:

<?xml version="1.0" encoding="iso-8859-1" ?>
<?meta name="GENERATOR" content="XML::Smart/1.6.8 Perl/5.006001 [MSWin
+32]" ?>
<phone type="home">555-1234</phone>

See the method apply_dtd() in the XML::Smart documentation to apply automatically a DTD to all your tree.

[pfaut]

That's not working for me. The 'type' attribute gets lost.

The code:

use XML::Smart;

my $xml = XML::Smart->new;
$xml->{customer}{phone} = "555-1234";
$xml->{customer}{phone}{type} = "home";

$xml->apply_dtd(<<EOF);
<?xml version="1.0" ?>
<!DOCTYPE customer [
<!ELEMENT customer (phone+)>
<!ELEMENT phone (#PCDATA)>
<!ATTLIST phone type PCDATA #REQUIRED>
]>
EOF

print $xml->data;

The results:

<?xml version="1.0" encoding="iso-8859-1" ?>
<?meta name="GENERATOR" content="XML::Smart/1.6.6 Perl/5.008 [MSWin32]
+" ?>
<!DOCTYPE customer [
<!ELEMENT customer (phone+)>
<!ELEMENT phone (#PCDATA)>
<!ATTLIST phone type PCDATA #REQUIRED>
]>
<customer>
  <phone>555-1234</phone>
</customer>

Use of uninitialized value in print at testxml.pl line 19.

Line 19 is print $xml->data.

[gmpassos]

The error is in your DTD syntax! You can't have PCDATA as attribute, since PCDATA is only for contents. You should use CDATA.

When you apply_dtd(), if some ELEMENT or ATTRIBUTE is not defined in the DTD it will be removed from the tree! So, type is removed since the line ATTLIST is wrong.

This code will work:

use XML::Smart;

my $xml = XML::Smart->new;
$xml->{customer}{phone} = "555-1234";
$xml->{customer}{phone}{type} = "home";

$xml->apply_dtd(<<EOF);
<?xml version="1.0" ?>
<!DOCTYPE customer [
<!ELEMENT customer (phone+)>
<!ELEMENT phone (#PCDATA)>
<!ATTLIST phone type CDATA #REQUIRED>
]>
EOF

print $xml->data;

Output:

<?xml version="1.0" encoding="iso-8859-1" ?>
<?meta name="GENERATOR" content="XML::Smart/1.6.8 Perl/5.006001 [MSWin
+32]" ?>
<!DOCTYPE customer [
<!ELEMENT customer (phone+)>
<!ELEMENT phone (#PCDATA)>
<!ATTLIST phone type CDATA #REQUIRED>
]>
<customer>
  <phone type="home">555-1234</phone>
</customer>