<?php
/**
* @file
* Hooks provided by the RDF module.
*/
/**
* @addtogroup hooks
* @{
*/
/**
* Allow modules to define RDF mappings for field bundles.
*
* Modules defining their own field bundles can specify which RDF semantics
* should be used to annotate these bundles. These mappings are then used for
* automatic RDFa output in the HTML code.
*
* @return
* A list of mapping structures, where each mapping is an associative array:
* - type: The name of an entity type (e.g., 'node', 'comment', and so on.)
* - bundle: The name of the bundle (e.g., 'page', 'blog', or
* RDF_DEFAULT_BUNDLE for default mappings.)
* - mapping: The mapping structure which applies to the entity type and
* bundle. A mapping structure is an array with keys corresponding to
* existing field instances in the bundle. Each field is then described in
* terms of the RDF mapping:
* - predicates: An array of RDF predicates which describe the relation
* between the bundle (RDF subject) and the value of the field (RDF
* object). This value is either some text, another bundle, or a URI in
* general.
* - datatype: Is used along with 'callback' to format data so that it is
* readable by machines. A typical example is a date which can be written
* in many different formats but should be translated into a uniform
* format for machine consumption.
* - callback: A function name to invoke for 'datatype'.
* - type: A string used to determine the type of RDFa markup which will be
* used in the final HTML output, depending on whether the RDF object is a
* literal text or another RDF resource.
* - rdftype: A special property used to define the type of the instance.
* Its value should be an array of RDF classes.
*
* @ingroup rdf
*/
function hook_rdf_mapping() {
return array(
array(
'type' => 'node',
'bundle' => 'blog',
'mapping' => array(
'rdftype' => array('sioct:Weblog'),
'title' => array(
'predicates' => array('dc:title'),
),
'created' => array(
'predicates' => array('dc:date', 'dc:created'),
'datatype' => 'xsd:dateTime',
'callback' => 'date_iso8601',
),
'body' => array(
'predicates' => array('content:encoded'),
),
'uid' => array(
'predicates' => array('sioc:has_creator'),
'type' => 'rel',
),
'name' => array(
'predicates' => array('foaf:name'),
),
),
),
);
}
/**
* Allow modules to define namespaces for RDF mappings.
*
* Many common namespace prefixes are defined in rdf_rdf_namespaces(). However,
* if a module implements hook_rdf_mapping() and uses a prefix that is not
* defined in rdf_rdf_namespaces(), this hook should be used to define the new
* namespace prefix.
*
* @return
* An associative array of namespaces where the key is the namespace prefix
* and the value is the namespace URI.
*
* @ingroup rdf
*/
function hook_rdf_namespaces() {
return array(
'content' => 'http://purl.org/rss/1.0/modules/content/',
'dc' => 'http://purl.org/dc/terms/',
'foaf' => 'http://xmlns.com/foaf/0.1/',
'og' => 'http://ogp.me/ns#',
'rdfs' => 'http://www.w3.org/2000/01/rdf-schema#',
'sioc' => 'http://rdfs.org/sioc/ns#',
'sioct' => 'http://rdfs.org/sioc/types#',
'skos' => 'http://www.w3.org/2004/02/skos/core#',
'xsd' => 'http://www.w3.org/2001/XMLSchema#',
);
}
/**
* @} End of "addtogroup hooks".
*/