# RDF::Trine::Serializer::TSV
# -----------------------------------------------------------------------------
=head1 NAME
RDF::Trine::Serializer::TSV - TSV Serializer
=head1 VERSION
This document describes RDF::Trine::Store version 1.014
=head1 SYNOPSIS
use RDF::Trine::Serializer::TSV;
my $serializer = RDF::Trine::Serializer::TSV->new();
=head1 DESCRIPTION
The RDF::Trine::Serializer::TSV class provides an API for serializing RDF
graphs to the TSV syntax.
=head1 METHODS
Beyond the methods documented below, this class inherits methods from the
L<RDF::Trine::Serializer> class.
=over 4
=cut
package RDF::Trine::Serializer::TSV;
use strict;
use warnings;
use base qw(RDF::Trine::Serializer);
use URI;
use Carp;
use Data::Dumper;
use Scalar::Util qw(blessed);
use RDF::Trine::Node;
use RDF::Trine::Statement;
use RDF::Trine::Error qw(:try);
######################################################################
our ($VERSION);
BEGIN {
$VERSION = '1.014';
$RDF::Trine::Serializer::serializer_names{ 'tsv' } = __PACKAGE__;
$RDF::Trine::Serializer::format_uris{ 'http://www.w3.org/ns/formats/TSV' } = __PACKAGE__;
foreach my $type (qw(text/tsv)) {
$RDF::Trine::Serializer::media_types{ $type } = __PACKAGE__;
}
}
######################################################################
=item C<< new >>
Returns a new TSV serializer object.
=cut
sub new {
my $class = shift;
my %args = @_;
my $self = bless( {}, $class);
return $self;
}
=item C<< serialize_model_to_file ( $fh, $model ) >>
Serializes the C<$model> to TSV, printing the results to the supplied
filehandle C<<$fh>>.
=cut
sub serialize_model_to_file {
my $self = shift;
my $file = shift;
my $model = shift;
my $st = RDF::Trine::Statement->new( map { RDF::Trine::Node::Variable->new($_) } qw(s p o) );
my $pat = RDF::Trine::Pattern->new( $st );
my $stream = $model->get_pattern( $pat, undef, orderby => [ qw(s ASC p ASC o ASC) ] );
my $iter = $stream->as_statements( qw(s p o) );
print {$file} join("\t", qw(s p o));
while (my $st = $iter->next) {
print {$file} $self->statement_as_string( $st );
}
}
=item C<< serialize_model_to_string ( $model ) >>
Serializes the C<$model> to TSV, returning the result as a string.
=cut
sub serialize_model_to_string {
my $self = shift;
my $model = shift;
my $st = RDF::Trine::Statement->new( map { RDF::Trine::Node::Variable->new($_) } qw(s p o) );
my $pat = RDF::Trine::Pattern->new( $st );
my $stream = $model->get_pattern( $pat, undef, orderby => [ qw(s ASC p ASC o ASC) ] );
my $iter = $stream->as_statements( qw(s p o) );
my $string = join("\t", qw(s p o)) . "\n";
while (my $st = $iter->next) {
my @nodes = $st->nodes;
$string .= $self->statement_as_string( $st );
}
return $string;
}
=item C<< serialize_iterator_to_file ( $file, $iter ) >>
Serializes the iterator to TSV, printing the results to the supplied
filehandle C<<$fh>>.
=cut
sub serialize_iterator_to_file {
my $self = shift;
my $file = shift;
my $iter = shift;
my $e = $iter->peek;
if (defined($e) and blessed($e) and $e->isa('RDF::Trine::Statement')) {
print {$file} join("\t", qw(?s ?p ?o)) . "\n";
while (my $st = $iter->next) {
print {$file} $self->statement_as_string( $st );
}
} elsif (defined($e) and blessed($e) and $e->isa('RDF::Trine::VariableBindings')) {
my @names = $iter->binding_names;
print {$file} join("\t", map { "?$_" } @names) . "\n";
while (my $r = $iter->next) {
print {$file} $self->result_as_string( $r, \@names );
}
}
}
=item C<< serialize_iterator_to_string ( $iter ) >>
Serializes the iterator to TSV, returning the result as a string.
=cut
sub serialize_iterator_to_string {
my $self = shift;
my $iter = shift;
# TODO: must print the header line corresponding to the bindings in the entire iterator...
my $string = '';
my $e = $iter->peek;
if (defined($e) and blessed($e) and $e->isa('RDF::Trine::Statement')) {
$string .= join("\t", qw(?s ?p ?o)) . "\n";
while (my $st = $iter->next) {
$string .= $self->statement_as_string( $st );
}
} elsif (defined($e) and blessed($e) and $e->isa('RDF::Trine::VariableBindings')) {
my @names = $iter->binding_names;
$string .= join("\t", map { "?$_" } @names) . "\n";
while (my $r = $iter->next) {
$string .= $self->result_as_string( $r, \@names );
}
}
return $string;
}
sub _serialize_bounded_description {
my $self = shift;
my $model = shift;
my $node = shift;
my $seen = shift || {};
# TODO: must print the header line, but only on the first (non-recursive) call to _serialize_bounded_description
return '' if ($seen->{ $node->sse }++);
my $iter = $model->get_statements( $node, undef, undef );
my $string = '';
while (my $st = $iter->next) {
my @nodes = $st->nodes;
$string .= $self->statement_as_string( $st );
if ($nodes[2]->isa('RDF::Trine::Node::Blank')) {
$string .= $self->_serialize_bounded_description( $model, $nodes[2], $seen );
}
}
return $string;
}
=item C<< result_as_string ( $result, \@names ) >>
Returns a string with the bound terms of the given RDF::Trine::VariableBindings
corresponding to the given C<@names> serialized in N-Triples format, separated
by tab characters.
=cut
sub result_as_string {
my $self = shift;
my $r = shift;
my $names = shift;
my @terms = map { $r->{ $_ } } @$names;
return join("\t", map { blessed($_) ? $_->as_ntriples : '' } @terms) . "\n";
}
=item C<< statement_as_string ( $st ) >>
Returns a string with the nodes of the given RDF::Trine::Statement serialized
in N-Triples format, separated by tab characters.
=cut
sub statement_as_string {
my $self = shift;
my $st = shift;
my @nodes = $st->nodes;
return join("\t", map { $_->as_ntriples } @nodes[0..2]) . "\n";
}
1;
__END__
=back
=head1 BUGS
Please report any bugs or feature requests to through the GitHub web interface
at L<https://github.com/kasei/perlrdf/issues>.
=head1 SEE ALSO
L<http://www.w3.org/TR/rdf-testcases/#ntriples>
=head1 AUTHOR
Gregory Todd Williams C<< <gwilliams@cpan.org> >>
=head1 COPYRIGHT
Copyright (c) 2006-2012 Gregory Todd Williams. This
program is free software; you can redistribute it and/or modify it under
the same terms as Perl itself.
=cut