perl xml::sax parsing - perl

Question

Hi I have an xml as below:
<employees>
<employee>
<firstname>John</firstname>
<lastname>Doe</lastname>
<age>gg</age>
<department>Operations</department>
<amount Ccy="EUR">100</amount>
<joinDate> 12/12/2011 </joinDate>
</employee>
<employee>
<firstname>John1111</firstname>
<lastname>Doe1111</lastname>
<age>gg</age>
<department>Operations</department>
<amount Ccy="EUR">200</amount>
<joinDate> 12/13/2011 </joinDate>
</employee>
</employees>
I would like to parse this using xml::sax. So I override start_element and end_element and characters methods. I have to handle two scenarios which i am not sure how to handle. 1) if joinDate is null then take the joinDate as sysdate. 2) sum up the amount and get a value as totalAmount. How to do this using XML::SAX module in perl.
Throw me some light which method i need to override to do this and small snippet of code would help.
Thanks,
Srikanth

Answer 1

It's pretty straightforward:
#!/usr/bin/perl
use strict;
use warnings;
use Data::Dumper;
use XML::SAX::ParserFactory;
use XML::SAX::PurePerl;
use Date::Calc 'Today';
my $today = sprintf("%02d/%02d/%4d", (Today())[1,2,0]);
# Alternatively if you can't use Date::Calc:
# my #localtime = localtime;
# my $today = sprintf("%02d/%02d/%4d", $localtime[4]+1, $localtime[2], $localtime[5]+1900);
my (#joindates, $total_amount, $buffer);
my $factory = new XML::SAX::ParserFactory;
my $handler = new XML::SAX::PurePerl;
my $parser = $factory->parser(
Handler => $handler,
Methods => {
characters => sub {
$buffer = shift->{Data};
$buffer =~ s/^\s+|\s+$//g;
},
end_element => sub {
return unless shift->{LocalName} =~ /^(amount|joinDate)$/;
push #joindates, $buffer || $today if $1 eq 'joinDate';
$total_amount += $buffer if $1 eq 'amount';
}
}
);
$parser->parse_uri("sample.xml");
print "Total amount: $total_amount\n";
printf("Join dates:\n%s\n", join("\n", #joindates));
Output:
Total amount: 300
Join dates:
12/12/2011
12/13/2012