NAME
XML::Atom::Microformats - parse microformats in Atom feeds
SYNOPSIS
use XML::Atom::Microformats;
my $feed = HTML::Microformats
->new_feed($xml, $base_uri)
->assume_profile(qw(hCard hCalendar));
print $feed->json(pretty => 1);
use RDF::TrineShortcuts qw(rdf_query);
my $results = rdf_query($sparql, $feed->model);
VERSION
0.00_00
DESCRIPTION
The XML::Atom::Microformats module brings the functionality of
HTML::Microformats to Atom 1.0 Syndication feeds. It finds microformats
embedded in the <content> elements (note: not <summary>) of Atom
entries.
The general pattern of usage is to create an XML::Atom::Microformats
object (which corresponds to an Atom 1.0 feed) using the "new_feed"
method; then ask for the data, as a Perl hashref, a JSON string, or an
RDF::Trine model.
Constructor
"$feed = XML::Atom::Microformats->new_feed($xml, $base_url)"
Constructs a feed object.
$xml is the Atom source (string) or an XML::LibXML::Document.
$base_url is the feed URL, important for resolving relative URL
references.
Profile Management
HTML::Microformats uses HTML profiles (i.e. the profile attribute on the
HTML <head> element) to detect which Microformats are used on a page.
Any microformats which do not have a profile URI declared will not be
parsed.
XML::Atom::Microformats uses a similar mechanism. Because Atom does not
have a <head> element, Atom <link> is used instead:
<link rel="profile" href="http://ufs.cc/x/hcalendar" />
These links can be used on a per-entry basis, or for the whole feed.
Because many pages fail to properly declare which profiles they use,
there are various profile management methods to tell
XML::Atom::Microformats to assume the presence of particular profile
URIs, even if they're actually missing.
"$feed->add_profile(@profiles)", "$feed->entry_add_profile($entryid,
@profiles)"
Using "add_profile" you can add one or more profile URIs, and they
are treated as if they were found on the document.
For example:
This is useful for adding profile URIs declared outside the document
itself (e.g. in HTTP headers).
"entry_add_profile" is a variant to allow you to add a profile which
applies only to one specific entry within the feed, if you know that
entry's ID.
"$feed->assume_profile(@microformats)",
"$feed->entry_assume_profile($entryid, @profiles)"
For example:
$feed->assume_profile(qw(hCard adr geo))
This method acts similarly to "add_profile" but allows you to use
names of microformats rather than URIs. Microformat names are case
sensitive, and must match HTML::Microformats::Foo module names.
"entry_assume_profile" is a variant to allow you to add a profile
which applies only to one specific entry within the feed, if you
know that entry's ID.
"$feed->assume_all_profiles",
"$feed->entry_assume_all_profiles($entryid)"
This method is equivalent to calling "assume_profile" for all known
microformats.
Parsing Microformats
Generally speaking, you can skip this. The "data", "json" and "model"
methods will automatically do this for you.
"$feed->parse_microformats"
Scans through the feed, finding microformat objects.
On subsequent calls, does nothing (as everything is already parsed).
"$feed->clear_microformats"
Forgets information gleaned by "parse_microformats" and thus allows
"parse_microformats" to be run again. This is useful if you've
modified added some profiles between runs of "parse_microformats".
Retrieving Data
These methods allow you to retrieve the feed's data, and do things with
it.
"$feed->objects($format)", "$feed->entry_objects($entryid, $format)"
$format is, for example, 'hCard', 'adr' or 'RelTag'.
Returns a list of objects of that type. (If called in scalar
context, returns an arrayref.)
Each object is, for example, an HTML::Microformat::hCard object, or
an HTML::Microformat::RelTag object, etc. See the relevent
documentation for details.
"entry_objects" is a variant to allow you to fetch data for one
specific entry within the feed, if you know that entry's ID.
"$feed->all_objects", "$feed->entry_all_objects($entryid)"
Returns a hashref of data. Each hashref key is the name of a
microformat (e.g. 'hCard', 'RelTag', etc), and the values are
arrayrefs of objects.
Each object is, for example, an HTML::Microformat::hCard object, or
an HTML::Microformat::RelTag object, etc. See the relevent
documentation for details.
"entry_all_objects" is a variant to allow you to fetch data for one
specific entry within the feed, if you know that entry's ID.
"$feed->json(%opts)", "$feed->entry_json($entryid, %opts)"
Returns data roughly equivalent to the "all_objects" method, but as
a JSON string.
%opts is a hash of options, suitable for passing to the JSON
module's to_json function. The 'convert_blessed' and 'utf8' options
are enabled by default, but can be disabled by explicitly setting
them to 0, e.g.
print $feed->json( pretty=>1, canonical=>1, utf8=>0 );
"entry_json" is a variant to allow you to fetch data for one
specific entry within the feed, if you know that entry's ID.
"$feed->model(%opts)", "$feed->entry_model($entryid, %opts)"
Returns data as an RDF::Trine::Model, suitable for serialising as
RDF or running SPARQL queries. Quads are used (rather than triples)
which allows you to trace statements to the entries from which they
came.
"entry_model" is a variant to allow you to fetch data for one
specific entry within the feed, if you know that entry's ID.
$opts{'atomowl'} is a boolean indicating whether or not to include
data from XML::Atom::OWL in the returned model. If enabled, this
always includes AtomOWL data for the whole feed (not just for a
specific entry), even if you use the "entry_model" method.
If RDF::RDFa::Parser 1.09_04 or above is installed, then
$opts{'atomowl'} will automatically pull in DataRSS data too.
"$feed->add_to_model($model, %opts)", "$feed->entry_add_to_model($entry,
$model, %opts)".
Adds data to an existing RDF::Trine::Model. Otherwise, the same as
"model".
BUGS
Please report any bugs to <http://rt.cpan.org/>.
SEE ALSO
XML::Atom::OWL, HTML::Microformats, RDF::RDFa::Parser.
AUTHOR
Toby Inkster <tobyink@cpan.org>.
COPYRIGHT
Copyright 2010 Toby Inkster
This library is free software; you can redistribute it and/or modify it
under the same terms as Perl itself.