perl parsing using sax - perl

Question

I would like to write a xml parsing script in Perl that prints all the firstname values from the following xml file using XML::SAX module.
<employees>
<employee>
<firstname>John</firstname>
<lastname>Doe</lastname>
<age>gg</age>
<department>Operations</department>
<amount Ccy="EUR">100</amount>
</employee>
<employee>
<firstname>Larry</firstname>
<lastname>Page</lastname>
<age>45</age>
<department>Accounts</department>
<amount Ccy="EUR">200</amount>
</employee>
<employee>
<firstname>Harry</firstname>
<lastname>Potter</lastname>
<age>50</age>
<department>Human Resources</department>
<amount Ccy="EUR">300</amount>
</employee>
</employees>
Can anyone help me with sample script?
I am a new to Perl.

Answer 1

Here's an example using XML::SAX. I've used XML::SAX::PurePerl.
#!/usr/bin/perl
use strict;
use warnings;
use Data::Dumper;
use XML::SAX::ParserFactory;
use XML::SAX::PurePerl;
my $characters;
my #firstnames;
my $factory = new XML::SAX::ParserFactory;
#Let's see which handlers we have available
#print Dumper $factory;
my $handler = new XML::SAX::PurePerl;
my $parser = $factory->parser(
Handler => $handler,
Methods => {
characters => sub {
$characters = shift->{Data};
},
end_element => sub {
push #firstnames, $characters if shift->{LocalName} eq 'firstname';
}
}
);
$parser->parse_uri("sample.xml");
print Dumper \#firstnames;
Output:
$VAR1 = [
'John',
'Larry',
'Harry'
];
I use $characters to hold character data, and push its contents onto #firstnames whenever I see a closing firstname tag.

Answer 2

Do you have any reason to stick with XML::Sax; If not then probably you can look for some other XML parsers in Perl (XML::Twig, XML::LibXML, XML::LibXMLReader, XML::Simple) and many more.
Here is a sample code to retrieve the firstname using XML::Twig.
use XML::Twig;
my $twig = XML::Twig->new ();
$twig->parsefile ('sample.xml');
my #firstname = map { $_->text } $twig->findnodes ('//firstname');