HTML::Microformats::Documentation::Notes - misc usage and design notes
The internals of HTML::Microformats are pretty complicated - best to steer clear of them. Here are three usage patterns that mostly avoid dealing with the internals:
Parse a page and use it as a single RDF graph.
A page can be parsed into an RDF::Trine::Model and queried using SPARQL.
use HTML::Microformats; use LWP::Simple qw[get]; use RDF::Query; my $page = 'http://example.net/'; my $graph = HTML::Microformats ->new_document(get($page), $page) ->assume_all_profiles ->parse_microformats ->model; my $query = RDF::Query->new(<<SPARQL); PREFIX foaf: <http://xmlns.com/foaf/0.1/> SELECT DISTINCT ?friendname ?friendpage WHERE { <$page> ?p ?friendpage . ?person foaf:name ?friendname ; foaf:page ?friendpage . FILTER ( isURI(?friendpage) && isLiteral(?friendname) && regex(str(?p), "^http://vocab.sindice.com/xfn#(.+)-hyperlink") ) } SPARQL my $results = $query->execute($graph); while (my $result = $results->next) { printf("%s <%s>\n", $result->{friendname}->literal_value, $result->{friendpage}->uri, ); }
Use the data method on each object.
The data method on microformat objects returns a hashref of useful data.
data
use HTML::Microformats; use LWP::Simple qw[get]; my $page = 'http://example.net/'; my @xfn_objs = HTML::Microformats ->new_document(get($page), $page) ->assume_all_profiles ->parse_microformats ->objects('XFN'); while (my $xfn = shift @xfn_objs) { printf("%s <%s>\n", $xfn->data->{title}, $xfn->data->{href}, ); }
(If you're wondering why the second example's simpler it's because it returns somewhat dumber data.)
Convert to other formats.
Various microformat objects have to_foo methods allowing the data to be exported in various formats..
to_foo
use HTML::Microformats; use LWP::Simple qw[get]; my $page = 'http://example.net/'; my @hcards = HTML::Microformats ->new_document(get($page), $page) ->assume_all_profiles ->parse_microformats ->objects('hCard'); print $_->to_vcard foreach @hcards;
Methods available are:
to_vcard (hCard objects)
to_vcard
Exports as vCard 3.0.
to_vcard4 (hCard objects)
to_vcard4
Exports as vCard 4.0.
to_vcard4_xml (hCard objects)
to_vcard4_xml
Exports as vCard XML.
to_icalendar (hCalendar, hEvent, hTodo, hFreebusy, hAlarm and hEntry objects)
to_icalendar
Exports as iCalendar.
to_atom (hAtom and hEntry objects)
to_atom
Exports as Atom 1.0.
to_kml (geo objects)
to_kml
Exports as KML 2.0.
serialialise_model(as => $format) (all microformat objects)
serialialise_model(as => $format)
Exports as RDF, serialised as $format. (Format can be 'RDFXML', 'Turtle', 'NTriples', 'RDFJSON'.)
$format
The get_foo, set_foo, add_foo, clear_foo methods defined in HTML::Microformats::Format work unreliably and are poorly documented. You're better off using the data method and inspecting the returned structure for the data you need. This will be fixed in the future.
get_foo
set_foo
add_foo
clear_foo
There are several parts of the code which are incredibly complicated and desperately need refactoring. This will be done at some point, so don't rely too much on their current behaviour.
stringify and _stringify_helper in HTML::Microformats::Utilities. The whole of HTML::Microformats::Mixin::Parser.
stringify
_stringify_helper
HTML::Microformats.
Toby Inkster <tobyink@cpan.org>.
Copyright 2008-2012 Toby Inkster
This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.
To install HTML::Microformats, copy and paste the appropriate command in to your terminal.
cpanm
cpanm HTML::Microformats
CPAN shell
perl -MCPAN -e shell install HTML::Microformats
For more information on module installation, please visit the detailed CPAN module installation guide.