package WWW::Finger::Webfinger;
use 5.010;
use common::sense;
use utf8;
use Carp 0;
use HTTP::LRDD 0.104;
use LWP::UserAgent 0;
use RDF::Query 2.900;
use RDF::Trine 0.135 qw[iri];
use URI 0;
use URI::Escape 0;
use XRD::Parser 0.102;
use parent qw(WWW::Finger::_GenericRDF);
BEGIN {
$WWW::Finger::Webfinger::AUTHORITY = 'cpan:TOBYINK';
$WWW::Finger::Webfinger::VERSION = '0.104';
}
sub speed { 100 }
sub new
{
my $class = shift;
my $ident = shift or croak "Need to supply an account address\n";
my $self = bless {}, $class;
$ident = "acct:$ident"
unless $ident =~ /^[a-z0-9\.\-\+]+:/i;
$ident = URI->new($ident);
return undef
unless $ident->scheme =~ /^(mailto|acct|xmpp)$/;
$self->{'ident'} = $ident;
my $lrdd = HTTP::LRDD->new('http://lrdd.net/rel/descriptor', 'describedby', 'lrdd', 'webfinger');
my @d = $lrdd->discover($ident);
$self->{'graph'} = $lrdd->process_all($ident);
$self->follow_seeAlso(0);
return undef
unless $self->{'graph'}->count_statements(iri($ident),undef,undef)
|| $self->{'graph'}->count_statements(undef,undef,iri($ident));
return $self;
}
sub _simple_sparql
{
my $self = shift;
my $where = '';
foreach my $p (@_)
{
$where .= " UNION " if length $where;
$where .= sprintf('{ <%s> <%s> ?x . } '
. 'UNION { ?z xrd:alias <%s> ; <%s> ?x . } '
. 'UNION { ?z <http://xmlns.com/foaf/0.1/account> <%s> ; <%s> ?x . } '
. 'UNION { ?z <http://xmlns.com/foaf/0.1/holdsAccount> <%s> ; <%s> ?x . }',
(''.$self->{'ident'}), $p,
(''.$self->{'ident'}), $p,
(''.$self->{'ident'}), $p,
(''.$self->{'ident'}), $p,
);
}
my $sparql = "PREFIX xrd: <http://ontologi.es/xrd#> SELECT DISTINCT ?x WHERE { $where }";
my $query = RDF::Query->new($sparql);
my $iter = $query->execute( $self->{'graph'} );
my @results;
while (my $row = $iter->next)
{
push @results, $row->{'x'}->literal_value
if $row->{'x'}->is_literal;
push @results, $row->{'x'}->uri
if $row->{'x'}->is_resource;
}
if (wantarray)
{
return @results;
}
if (@results)
{
return $results[0];
}
return;
}
sub webid
{
return (shift)->SUPER::webid(@_);
}
1;
__END__
=head1 NAME
WWW::Finger::Webfinger - WWW::Finger module for Webfinger
=head1 DESCRIPTION
Webfinger is currently a very unstable specification, with implementation details
changing all the time. Given this instability, it seems prudent to describe the
protocol, as implemented by this package.
Given an e-mail-like identifier, the package will prepend "acct:" to it, assuming that
the identifier doesn't already have a URI scheme. This identifier will now be called
[ident].
The package looks up the host-meta file associated with the host for [ident].
It is assumed to be formatted according to the draft-hammer-hostmeta-05
Internet Draft L<http://tools.ietf.org/html/draft-hammer-hostmeta-05> and
XRD Working Draft 10 <http://www.oasis-open.org/committees/download.php/35274/xrd-1.0-wd10.html>.
Both these drafts are dated 19 November 2009.
A link template will be extracted from the host-meta for the host using either
of the following two relationships: L<http://lrdd.net/rel/descriptor>,
L<http://www.iana.org/assignments/relation/lrdd>. (Neither is prioritised, so
if both exist and have different templates, hilarity will ensue.)
The token "{uri}" in the link template will be replaced with the URL-encoded
version of [ident] to create an account descriptor URI.
The account descriptor URI is fetched via HTTP GET with an Accept header
asking for RDF/XML, Turtle, RDF/JSON or XRD. The result is parsed for account
description data if it has status code 200 (OK).
The following relationships/properties are understood in the account
description:
=over
=item * http://xmlns.com/foaf/0.1/name
=item * http://xmlns.com/foaf/0.1/homepage
=item * http://webfinger.net/rel/profile-page
=item * http://xmlns.com/foaf/0.1/weblog
=item * http://xmlns.com/foaf/0.1/mbox
=item * http://webfinger.net/rel/avatar
=item * http://xmlns.com/foaf/0.1/img
=item * http://xmlns.com/foaf/0.1/depiction
=item * http://ontologi.es/sparql#endpoint
=back
As well as the standard WWW::Finger methods, WWW::Finger::Webfinger provides this
additional method:
=over
=item C<< get($p1, $p2, ...) >>
$p1, $p2 and are RDF predicate URIs, XRD Link@rel values, or XRD Property@type values
# Returns phone numbers...
$finger->get('http://xmlns.com/foaf/0.1/phone',
'http://rdf.data-vocabulary.org/#tel');
# Salmon-style magic keys
$finger->get('magic-public-key');
=back
=head1 SEE ALSO
L<WWW::Finger>, L<XRD::Parser>, L<HTTP::LRDD>.
L<http://code.google.com/p/webfinger/>.
=head1 AUTHOR
Toby Inkster, E<lt>tobyink@cpan.orgE<gt>
=head1 COPYRIGHT AND LICENCE
Copyright (C) 2009-2012 by Toby Inkster
This library is free software; you can redistribute it and/or modify
it under the same terms as Perl itself.
=head1 DISCLAIMER OF WARRANTIES
THIS PACKAGE IS PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR IMPLIED
WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
=cut