#!/usr/bin/perl -w
use strict;
use warnings;
BEGIN {
$XML::SAX::ParserPackage = "XML::LibXML::SAX";
}
use XML::SAX::ParserFactory;
my $metadataHandler = innerSAX->new();
my $oaiHandler = outerSAX->new(metadataHandler => $metadataHandler,
oaiNS => "
http://www.openarchives.org/OAI/2.0/");
my $parser = XML::SAX::ParserFactory->parser(Handler => $oaiHandler);
$parser->parse_file("test.rdf");
package outerSAX;
use base qw(XML::SAX::Base);
sub new {
my ($class, %opts) = @_;
my $self = bless \%opts, ref($class) || $class;
$self->set_handler( undef );
return $self;
}
sub start_element {
my ($self, $element) = @_;
return $self->SUPER::start_element($element) unless $element->{NamespaceURI} eq $self->{oaiNS};
if ( $element->{LocalName} eq 'metadata' ) {
$self->{ OLD_Handler } = $self->get_handler();
$self->set_handler( $self->{metadataHandler} );
}
else {
return $self->SUPER::start_element($element)};
}
sub end_element {
my ($self, $element) = @_;
return $self->SUPER::end_element($element) unless $element->{NamespaceURI} eq $self->{oaiNS};
if ( $element->{LocalName} eq 'metadata' ) {
$self->set_handler( $self->{OLD_Handler} );
}
else {
$self->SUPER::end_element($element);
}
}
package innerSAX;
use base qw(XML::SAX::Base);
use XML::LibXML::SAX::Builder;
sub new {
my ($class, %opts) = @_;
my $self = bless \%opts, ref($class) || $class;
$self->{'tagStack'} = [];
return $self;
}
sub start_element {
my ($self, $element) = @_;
unless ( $self->{'tagStack'}[0] ) {
my $builder = XML::LibXML::SAX::Builder->new() or die "cannot instantiate SAX builder";
$self->set_handler($builder);
$self->SUPER::start_document(); # i.e. $builder->start_document();
# DEBUG ME: warnings occur here
$self->SUPER::start_element($element);
}
else {
$self->SUPER::start_element($element)};
push(@{$self->{'tagStack'}}, $element->{Name});
}
sub end_element {
my ($self, $element) = @_;
$self->SUPER::end_element($element);
pop (@{$self->{'tagStack'}});
unless ( $self->{'tagStack'}[0] ) {
my $hdl = $self->get_handler();
$self->set_handler(undef);
# convert fragment to document, do something with it (in real life: XSLT)
my $fragment = $hdl->done();
my $child = $fragment->firstChild();
$child = $child->nextSibling while $child && $child->nodeName eq "#text";
my $tempdoc = XML::LibXML::Document->createDocument() or die "cannot create new Document";
$tempdoc->addChild($child) or die "cannot addChild";
print $tempdoc->toString;
}
}
1;
