insideout10 / wordlift-plugin

src/includes/class-wordlift-schema-service.php

Indentation +1651 added lines, -1651 removed lines

@@ -18,1656 +18,1656 @@
  */
 class Wordlift_Schema_Service {
 
-	/**
-	 * The 'location created' field name.
-	 *
-	 * @since 3.5.0
-	 */
-	const FIELD_LOCATION_CREATED = 'wl_location_created';
-
-	/**
-	 * The 'topic' field name.
-	 *
-	 * @since 3.5.0
-	 */
-	const FIELD_TOPIC = 'wl_topic';
-
-	/**
-	 * The 'author' field name.
-	 *
-	 * @since 3.1.0
-	 */
-	const FIELD_AUTHOR = 'wl_author';
-
-	/**
-	 * The 'same as' field name.
-	 *
-	 * @since 3.1.0
-	 */
-	const FIELD_SAME_AS = 'entity_same_as';
-
-	/**
-	 * The 'date start' field name.
-	 *
-	 * @since 3.1.0
-	 */
-	const FIELD_DATE_START = 'wl_cal_date_start';
-
-	/**
-	 * The 'date end' field name.
-	 *
-	 * @since 3.1.0
-	 */
-	const FIELD_DATE_END = 'wl_cal_date_end';
-
-	/**
-	 * The 'location' field name.
-	 *
-	 * @since 3.1.0
-	 */
-	const FIELD_LOCATION = 'wl_location';
-
-	/**
-	 * The 'founder' field name.
-	 *
-	 * @since 3.1.0
-	 */
-	const FIELD_FOUNDER = 'wl_founder';
-
-	/**
-	 * The 'knows' field name.
-	 *
-	 * @since 3.1.0
-	 */
-	const FIELD_KNOWS = 'wl_knows';
-
-	/**
-	 * The 'birth date' field name.
-	 *
-	 * @since 3.1.0
-	 */
-	const FIELD_BIRTH_DATE = 'wl_birth_date';
-
-	/**
-	 * The 'birth place' field name.
-	 *
-	 * @since 3.1.0
-	 */
-	const FIELD_BIRTH_PLACE = 'wl_birth_place';
-
-	/**
-	 * The 'latitude' field name.
-	 *
-	 * @since 3.1.0
-	 */
-	const FIELD_GEO_LATITUDE = 'wl_geo_latitude';
-
-	/**
-	 * The 'longitude' field name.
-	 *
-	 * @since 3.1.0
-	 */
-	const FIELD_GEO_LONGITUDE = 'wl_geo_longitude';
-
-	/**
-	 * The 'streetAddress' field name.
-	 *
-	 * @since 3.1.0
-	 */
-	const FIELD_ADDRESS = 'wl_address';
-
-	/**
-	 * The 'postOfficeBoxNumber' field name.
-	 *
-	 * @since 3.3.0
-	 */
-	const FIELD_ADDRESS_PO_BOX = 'wl_address_post_office_box';
-
-	/**
-	 * The 'postalCode' field name.
-	 *
-	 * @since 3.3.0
-	 */
-	const FIELD_ADDRESS_POSTAL_CODE = 'wl_address_postal_code';
-
-	/**
-	 * The 'addressLocality' field name.
-	 *
-	 * @since 3.3.0
-	 */
-	const FIELD_ADDRESS_LOCALITY = 'wl_address_locality';
-	/**
-	 * The 'addressRegion' field name.
-	 *
-	 * @since 3.3.0
-	 */
-	const FIELD_ADDRESS_REGION = 'wl_address_region';
-
-	/**
-	 * The 'addressCountry' field name.
-	 *
-	 * @since 3.3.0
-	 */
-	const FIELD_ADDRESS_COUNTRY = 'wl_address_country';
-
-	/**
-	 * The 'entity type' field name.
-	 *
-	 * @since 3.1.0
-	 */
-	const FIELD_ENTITY_TYPE = 'wl_entity_type_uri';
-
-	/**
-	 * The 'email' field name.
-	 *
-	 * @since 3.2.0
-	 */
-	const FIELD_EMAIL = 'wl_email';
-
-	/**
-	 * The 'affiliation' field name.
-	 *
-	 * @since 3.2.0
-	 */
-	const FIELD_AFFILIATION = 'wl_affiliation';
-
-	/**
-	 * The 'telephone' field name.
-	 *
-	 * @since 3.8.0
-	 */
-	const FIELD_TELEPHONE = 'wl_schema_telephone';
-
-	/**
-	 * The 'legalName' field name.
-	 *
-	 * @since 3.12.0
-	 */
-	const FIELD_LEGAL_NAME = 'wl_schema_legal_name';
-
-	/**
-	 * The 'recipeCuisine' field name.
-	 *
-	 * @since 3.14.0
-	 */
-	const FIELD_RECIPE_CUISINE = 'wl_schema_recipe_cuisine';
-
-	/**
-	 * The 'recipeIngredient' field name.
-	 *
-	 * @since 3.14.0
-	 */
-	const FIELD_RECIPE_INGREDIENT = 'wl_schema_recipe_ingredient';
-
-	/**
-	 * The 'calories' field name.
-	 *
-	 * @since 3.14.0
-	 */
-	const FIELD_NUTRITION_INFO_CALORIES = 'wl_schema_nutrition_information_calories';
-
-	/**
-	 * The 'recipeInstructions' field name.
-	 *
-	 * @since 3.14.0
-	 */
-	const FIELD_RECIPE_INSTRUCTIONS = 'wl_schema_recipe_instructions';
-
-	/**
-	 * The 'recipeYield' field name.
-	 *
-	 * @since 3.14.0
-	 */
-	const FIELD_RECIPE_YIELD = 'wl_schema_recipe_yield';
-
-	/**
-	 * The 'prepTime' field name.
-	 *
-	 * @since 3.14.0
-	 */
-	const FIELD_PREP_TIME = 'wl_schema_prep_time';
-
-	/**
-	 * The 'cookTime' field name.
-	 *
-	 * @since 3.14.0
-	 */
-	const FIELD_COOK_TIME = 'wl_schema_cook_time';
-
-	/**
-	 * The 'totalTime' field name.
-	 *
-	 * @since 3.14.0
-	 */
-	const FIELD_TOTAL_TIME = 'wl_schema_total_time';
-
-	/**
-	 * The 'performer' field name.
-	 *
-	 * @since 3.18.0
-	 */
-	const FIELD_PERFORMER = 'wl_schema_performer';
-
-	/**
-	 * The 'offers' field name.
-	 *
-	 * @since 3.18.0
-	 */
-	const FIELD_OFFERS = 'wl_schema_offers';
-
-	/**
-	 * The 'availablity' field name.
-	 *
-	 * @since 3.18.0
-	 */
-	const FIELD_AVAILABILITY = 'wl_schema_availability';
-
-	/**
-	 * The 'inventoryLevel' field name.
-	 *
-	 * @since 3.18.0
-	 */
-	const FIELD_INVENTORY_LEVEL = 'wl_schema_inventory_level';
-
-	/**
-	 * The 'price' field name.
-	 *
-	 * @since 3.18.0
-	 */
-	const FIELD_PRICE = 'wl_schema_price';
-
-	/**
-	 * The 'priceCurrency' field name.
-	 *
-	 * @since 3.18.0
-	 */
-	const FIELD_PRICE_CURRENCY = 'wl_schema_price_currency';
-
-	/**
-	 * The 'availabilityStarts' field name.
-	 *
-	 * @since 3.18.0
-	 */
-	const FIELD_AVAILABILITY_STARTS = 'wl_schema_availability_starts';
-
-	/**
-	 * The 'availabilityEnds' field name.
-	 *
-	 * @since 3.18.0
-	 */
-	const FIELD_AVAILABILITY_ENDS = 'wl_schema_availability_ends';
-
-	/**
-	 * The 'validFrom' field name.
-	 *
-	 * @since 3.18.0
-	 */
-	const FIELD_VALID_FROM = 'wl_schema_valid_from';
-
-	/**
-	 * The 'priceValidUntil' field name.
-	 *
-	 * @since 3.18.0
-	 */
-	const FIELD_PRICE_VALID_UNTIL = 'wl_schema_valid_until';
-
-	/**
-	 * The 'itemOffered' field name.
-	 *
-	 * @since 3.18.0
-	 */
-	const FIELD_ITEM_OFFERED = 'wl_schema_item_offered';
-
-	/**
-	 * The 'URI' data type name.
-	 *
-	 * @since 3.1.0
-	 */
-	const DATA_TYPE_URI = 'uri';
-
-	/**
-	 * The 'date' data type name.
-	 *
-	 * @since 3.1.0
-	 */
-	const DATA_TYPE_DATE = 'date';
-
-	/**
-	 * The 'dateTime' data type name.
-	 *
-	 * @since 3.15.0
-	 */
-	const DATA_TYPE_DATE_TIME = 'dateTime';
-
-	/**
-	 * The 'time' data type name.
-	 *
-	 * @since 3.14.0
-	 */
-	const DATA_TYPE_DURATION = 'duration';
-
-	/**
-	 * The 'double' data type name.
-	 *
-	 * @since 3.1.0
-	 */
-	const DATA_TYPE_DOUBLE = 'double';
-
-	/**
-	 * The 'string' data type name.
-	 *
-	 * @since 3.1.0
-	 */
-	const DATA_TYPE_STRING = 'string';
-
-	/**
-	 * The multiline text data type name.
-	 *
-	 * @since 3.14.0
-	 */
-	const DATA_TYPE_MULTILINE = 'multiline';
-
-	/**
-	 * The 'integer' data type name.
-	 *
-	 * @since 3.1.0
-	 */
-	const DATA_TYPE_INTEGER = 'int';
-
-	/**
-	 * The 'boolean' data type name.
-	 *
-	 * @since 3.1.0
-	 */
-	const DATA_TYPE_BOOLEAN = 'bool';
-
-	/**
-	 * The schema.org Event type URI.
-	 *
-	 * @since 3.1.0
-	 */
-	const SCHEMA_EVENT_TYPE = 'http://schema.org/Event';
-
-	/**
-	 * The schema.org Offer type URI.
-	 *
-	 * @since 3.18.0
-	 */
-	const SCHEMA_OFFER_TYPE = 'http://schema.org/Offer';
-
-	/**
-	 * The Schema service singleton instance.
-	 *
-	 * @since  3.1.0
-	 * @access private
-	 * @var \Wordlift_Schema_Service $instance The Schema service singleton instance.
-	 */
-	private static $instance;
-
-	/**
-	 * WordLift's schema.
-	 *
-	 * @since  3.1.0
-	 * @access private
-	 * @var array $schema WordLift's schema.
-	 */
-	private $schema;
-
-	/**
-	 * The Log service.
-	 *
-	 * @since  3.1.0
-	 * @access private
-	 * @var \Wordlift_Log_Service $log The Log service.
-	 */
-	private $log;
-
-	/**
-	 * The {@link Wordlift_Post_Property_Storage_Factory} instance.
-	 *
-	 * @since  3.15.0
-	 * @access private
-	 * @var \Wordlift_Storage_Factory $storage_factory The {@link Wordlift_Post_Property_Storage_Factory} instance.
-	 */
-	private $storage_factory;
-
-	/**
-	 * The {@link Wordlift_Sparql_Tuple_Rendition_Factory} instance.
-	 *
-	 * @since  3.15.0
-	 * @access private
-	 * @var \Wordlift_Sparql_Tuple_Rendition_Factory $rendition_factory The {@link Wordlift_Sparql_Tuple_Rendition_Factory} instance.
-	 */
-	private $rendition_factory;
-
-	/**
-	 * The {@link Wordlift_Configuration_Service} instance.
-	 *
-	 * @since  3.15.0
-	 * @access private
-	 * @var \Wordlift_Configuration_Service $configuration_service The {@link Wordlift_Configuration_Service} instance.
-	 */
-	private $configuration_service;
-
-	/**
-	 * The web site configured language code.
-	 *
-	 * @since  3.15.0
-	 * @access private
-	 * @var string $language_code The web site configured language code.
-	 */
-	private $language_code;
-
-	/**
-	 * Wordlift_Schema_Service constructor.
-	 *
-	 * @since 3.1.0
-	 *
-	 * @param \Wordlift_Storage_Factory                $storage_factory       The {@link Wordlift_Post_Property_Storage_Factory} instance.
-	 * @param \Wordlift_Sparql_Tuple_Rendition_Factory $rendition_factory     The {@link Wordlift_Sparql_Tuple_Rendition_Factory} instance.
-	 * @param \Wordlift_Configuration_Service          $configuration_service The {@link Wordlift_Configuration_Service} instance.
-	 */
-	public function __construct( $storage_factory, $rendition_factory, $configuration_service ) {
-
-		$this->log = Wordlift_Log_Service::get_logger( 'Wordlift_Schema_Service' );
-
-		$this->storage_factory       = $storage_factory;
-		$this->rendition_factory     = $rendition_factory;
-		$this->configuration_service = $configuration_service;
-		$this->language_code         = $this->configuration_service->get_language_code();
-
-		// Set the taxonomy data.
-		// Note: parent types must be defined before child types.
-		$this->schema = array(
-			'article'       => $this->get_article_schema(),
-			'thing'         => $this->get_thing_schema(),
-			'creative-work' => $this->get_creative_work_schema(),
-			'event'         => $this->get_event_schema(),
-			'organization'  => $this->get_organization_schema(),
-			'person'        => $this->get_person_schema(),
-			'place'         => $this->get_place_schema(),
-			'localbusiness' => $this->get_local_business_schema(),
-			'recipe'        => $this->get_recipe_schema(),
-			'web-page'      => $this->get_web_page_schema(),
-			'offer'         => $this->get_offer_schema(),
-		);
-
-		// Create a singleton instance of the Schema service, useful to provide static functions to global functions.
-		self::$instance = $this;
-
-	}
-
-	/**
-	 * Get a reference to the Schema service.
-	 *
-	 * @since 3.1.0
-	 *
-	 * @return Wordlift_Schema_Service A reference to the Schema service.
-	 */
-	public static function get_instance() {
-
-		return self::$instance;
-	}
-
-	/**
-	 * Get the properties for a field with the specified key. The key is used as
-	 * meta key when the field's value is stored in WordPress meta data table.
-	 *
-	 * @since 3.6.0
-	 *
-	 * @param string $key The field's key.
-	 *
-	 * @return null|array An array of field's properties or null if the field is not found.
-	 */
-	public function get_field( $key ) {
-
-		// Parse each schema's fields until we find the one we're looking for, then
-		// return its properties.
-		foreach ( $this->schema as $_ => $schema ) {
-
-			if ( ! isset( $schema['custom_fields'] ) ) {
-				break;
-			}
-
-			foreach ( $schema['custom_fields'] as $field => $props ) {
-				if ( $key === $field ) {
-					return $props;
-				}
-			}
-		}
-
-		return null;
-	}
-
-	/**
-	 * Get all renditions for each WordLift's schema.
-	 *
-	 * @since 3.18.0
-	 *
-	 * @return array An array with the schema renditions.
-	 */
-	public function get_renditions() {
-		// Get the custom fields.
-		$renditions = array_reduce(
-			$this->schema,
-			function ( $carry, $item ) {
-				return array_merge( $carry, $item['linked_data'] );
-			},
-			array()
-		);
-
-		// Return the schemas.
-		return $renditions;
-	}
-
-	/**
-	 * Get the WordLift's schema.
-	 *
-	 * @param string $name The schema name.
-	 *
-	 * @return array|null An array with the schema configuration or NULL if the schema is not found.
-	 *
-	 * @since 3.1.0
-	 */
-	public function get_schema( $name ) {
-		// Check if the schema exists and, if not, return NULL.
-		if ( ! isset( $this->schema[ $name ] ) ) {
-			return null;
-		}
-
-		// Return the requested schema.
-		return $this->schema[ $name ];
-	}
-
-	/**
-	 * Get the WordLift's schema trough schema type uri.
-	 *
-	 * @param string $uri The schema uri.
-	 *
-	 * @return array|null An array with the schema configuration or NULL if the schema is not found.
-	 *
-	 * @since 3.3.0
-	 */
-	public function get_schema_by_uri( $uri ) {
-
-		foreach ( $this->schema as $name => $schema ) {
-			if ( $schema['uri'] === $uri ) {
-				return $schema;
-			}
-		}
-
-		return null;
-	}
-
-	/**
-	 * Get the 'thing' schema.
-	 *
-	 * @return array An array with the schema configuration.
-	 *
-	 * @since 3.1.0
-	 */
-	private function get_thing_schema() {
-
-		return array(
-			'css_class'     => 'wl-thing',
-			'uri'           => 'http://schema.org/Thing',
-			'same_as'       => array( '*' ),
-			// set as default.
-			'custom_fields' => array(
-				self::FIELD_SAME_AS                            => array(
-					'predicate'   => 'http://schema.org/sameAs',
-					'type'        => self::DATA_TYPE_URI,
-					'export_type' => 'http://schema.org/Thing',
-					'constraints' => array(
-						'cardinality' => INF,
-					),
-					// We need a custom metabox.
-					'input_field' => 'sameas',
-				),
-				// Add the schema:url property.
-				Wordlift_Schema_Url_Property_Service::META_KEY => Wordlift_Schema_Url_Property_Service::get_instance()
-																									  ->get_compat_definition(),
-			),
-			// {{sameAs}} not present in the microdata template,
-			// because it is treated separately in *wl_content_embed_item_microdata*
-			'templates'     => array(
-				'subtitle' => '{{id}}',
-			),
-			'linked_data'   => array(
-				// ### Title to rdfs:label.
-				$this->rendition_factory->create(
-					$this->storage_factory->post_title(),
-					Wordlift_Query_Builder::RDFS_LABEL_URI,
-					null,
-					$this->language_code
-				),
-				// ### Title to dct:title.
-				$this->rendition_factory->create(
-					$this->storage_factory->post_title(),
-					'http://purl.org/dc/terms/title',
-					null,
-					$this->language_code
-				),
-				// ### Alternative title to rdfs:label.
-				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( Wordlift_Entity_Service::ALTERNATIVE_LABEL_META_KEY ),
-					Wordlift_Query_Builder::RDFS_LABEL_URI,
-					null,
-					$this->language_code
-				),
-				// ### Alternative title to dct:title.
-				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( Wordlift_Entity_Service::ALTERNATIVE_LABEL_META_KEY ),
-					'http://purl.org/dc/terms/title',
-					null,
-					$this->language_code
-				),
-				// ### Title to schema:name.
-				$this->rendition_factory->create(
-					$this->storage_factory->post_title(),
-					'http://schema.org/name',
-					null,
-					$this->language_code
-				),
-				// ### Alternative title to schema:alterName.
-				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( Wordlift_Entity_Service::ALTERNATIVE_LABEL_META_KEY ),
-					'http://schema.org/alternateName',
-					null,
-					$this->language_code
-				),
-				// ### schema:url.
-				$this->rendition_factory->create(
-					$this->storage_factory->url_property(),
-					Wordlift_Query_Builder::SCHEMA_URL_URI,
-					self::DATA_TYPE_URI
-				),
-				// ### schema:description.
-				$this->rendition_factory->create(
-					$this->storage_factory->post_description_no_tags_no_shortcodes(),
-					'http://schema.org/description',
-					null,
-					$this->language_code
-				),
-				// ### owl:sameAs.
-				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( self::FIELD_SAME_AS ),
-					'http://www.w3.org/2002/07/owl#sameAs',
-					self::DATA_TYPE_URI
-				),
-				// ### rdf:type.
-				$this->rendition_factory->create(
-					$this->storage_factory->schema_class(),
-					Wordlift_Query_Builder::RDFS_TYPE_URI,
-					self::DATA_TYPE_URI
-				),
-				// ### schema:image.
-				$this->rendition_factory->create(
-					$this->storage_factory->post_images(),
-					Wordlift_Query_Builder::SCHEMA_IMAGE_URI,
-					self::DATA_TYPE_URI
-				),
-				// ### dct:relation.
-				$this->rendition_factory->create(
-					$this->storage_factory->relations(),
-					Wordlift_Query_Builder::DCTERMS_RELATION_URI,
-					self::DATA_TYPE_URI
-				),
-			),
-		);
-
-	}
-
-	/**
-	 * Get the 'web-page' schema.
-	 *
-	 * @return array An array with the schema configuration.
-	 *
-	 * @since 3.18.0
-	 */
-	private function get_web_page_schema() {
-
-		return array(
-			'css_class'   => 'wl-webpage',
-			'uri'         => 'http://schema.org/WebPage',
-			'linked_data' => array(
-				// ### schema:headline.
-				$this->rendition_factory->create(
-					$this->storage_factory->post_title(),
-					'http://schema.org/headline',
-					null,
-					$this->language_code
-				),
-				// ### schema:url.
-				$this->rendition_factory->create(
-					$this->storage_factory->url_property(),
-					Wordlift_Query_Builder::SCHEMA_URL_URI,
-					self::DATA_TYPE_URI
-				),
-				// ### rdf:type.
-				$this->rendition_factory->create(
-					$this->storage_factory->schema_class(),
-					Wordlift_Query_Builder::RDFS_TYPE_URI,
-					self::DATA_TYPE_URI
-				),
-				// ### dcterms:references.
-				$this->rendition_factory->create(
-					$this->storage_factory->relations(),
-					Wordlift_Query_Builder::DCTERMS_REFERENCES_URI,
-					self::DATA_TYPE_URI,
-					$this->language_code
-				),
-			),
-		);
-
-	}
-
-	/**
-	 * Get the 'creative work' schema.
-	 *
-	 * @return array An array with the schema configuration.
-	 *
-	 * @since 3.1.0
-	 */
-	private function get_creative_work_schema() {
-
-		$schema = array(
-			'label'         => 'CreativeWork',
-			'description'   => 'A creative work (or a Music Album).',
-			'parents'       => array( 'thing' ),
-			// Give term slug as parent.
-			'css_class'     => 'wl-creative-work',
-			'uri'           => 'http://schema.org/CreativeWork',
-			'same_as'       => array(
-				'http://schema.org/MusicAlbum',
-				'http://schema.org/Product',
-			),
-			'custom_fields' => array(
-				self::FIELD_AUTHOR => array(
-					'predicate'   => 'http://schema.org/author',
-					'type'        => self::DATA_TYPE_URI,
-					'export_type' => 'http://schema.org/Person',
-					'constraints' => array(
-						'uri_type'    => array( 'Person', 'Organization' ),
-						'cardinality' => INF,
-					),
-				),
-			),
-			'linked_data'   => array(
-				// ### schema:author.
-				$this->rendition_factory->create(
-					$this->storage_factory->author_uri(),
-					Wordlift_Query_Builder::SCHEMA_AUTHOR_URI,
-					self::DATA_TYPE_URI
-				),
-			),
-			'templates'     => array(
-				'subtitle' => '{{id}}',
-			),
-		);
-
-		// Merge the custom fields with those provided by the thing schema.
-		$parent_schema           = $this->get_thing_schema();
-		$schema['custom_fields'] = array_merge( $schema['custom_fields'], $parent_schema['custom_fields'] );
-		$schema['linked_data']   = array_merge( $schema['linked_data'], $parent_schema['linked_data'] );
-
-		return $schema;
-	}
-
-	/**
-	 * Get the 'event' schema.
-	 *
-	 * @return array An array with the schema configuration.
-	 *
-	 * @since 3.1.0
-	 */
-	private function get_event_schema() {
-
-		$schema = array(
-			'label'         => 'Event',
-			'description'   => 'An event . ',
-			'parents'       => array( 'thing' ),
-			'css_class'     => 'wl-event',
-			'uri'           => self::SCHEMA_EVENT_TYPE,
-			'same_as'       => array( 'http://dbpedia.org/ontology/Event' ),
-			'custom_fields' => array(
-				self::FIELD_DATE_START => array(
-					'predicate'   => 'http://schema.org/startDate',
-					'type'        => self::DATA_TYPE_DATE,
-					'export_type' => 'xsd:dateTime',
-					'constraints' => '',
-				),
-				self::FIELD_DATE_END   => array(
-					'predicate'   => 'http://schema.org/endDate',
-					'type'        => self::DATA_TYPE_DATE,
-					'export_type' => 'xsd:dateTime',
-					'constraints' => '',
-				),
-				self::FIELD_LOCATION   => array(
-					'predicate'   => 'http://schema.org/location',
-					'type'        => self::DATA_TYPE_URI,
-					'export_type' => 'http://schema.org/PostalAddress',
-					'constraints' => array(
-						'uri_type'    => array( 'Place', 'LocalBusiness' ),
-						'cardinality' => INF,
-					),
-				),
-				self::FIELD_PERFORMER  => array(
-					'predicate'   => 'http://schema.org/performer',
-					'type'        => self::DATA_TYPE_URI,
-					'export_type' => 'http://schema.org/Person',
-					'constraints' => array(
-						'uri_type'    => array( 'Person', 'Organization' ),
-						'cardinality' => INF,
-					),
-				),
-				self::FIELD_OFFERS     => array(
-					'predicate'   => 'http://schema.org/offers',
-					'type'        => self::DATA_TYPE_URI,
-					'export_type' => 'http://schema.org/Offer',
-					'constraints' => array(
-						'uri_type'    => array( 'Offer' ),
-						'cardinality' => INF,
-					),
-				),
-			),
-			'linked_data'   => array(
-				// ### schema:startDate.
-				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( self::FIELD_DATE_START ),
-					'http://schema.org/startDate',
-					self::DATA_TYPE_DATE_TIME
-				),
-				// ### schema:endDate.
-				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( self::FIELD_DATE_END ),
-					'http://schema.org/endDate',
-					self::DATA_TYPE_DATE_TIME
-				),
-				// ### schema:location.
-				$this->rendition_factory->create(
-					$this->storage_factory->post_meta_to_uri( self::FIELD_LOCATION ),
-					'http://schema.org/location',
-					self::DATA_TYPE_URI
-				),
-				// ### schema:performer.
-				$this->rendition_factory->create(
-					$this->storage_factory->post_meta_to_uri( self::FIELD_PERFORMER ),
-					'http://schema.org/performer',
-					self::DATA_TYPE_URI
-				),
-				// ### schema:offers.
-				$this->rendition_factory->create(
-					$this->storage_factory->post_meta_to_uri( self::FIELD_OFFERS ),
-					'http://schema.org/offers',
-					self::DATA_TYPE_URI
-				),
-			),
-			'templates'     => array(
-				'subtitle' => '{{id}}',
-			),
-		);
-
-		// Merge the custom fields with those provided by the thing schema.
-		$parent_schema           = $this->get_thing_schema();
-		$schema['custom_fields'] = array_merge( $schema['custom_fields'], $parent_schema['custom_fields'] );
-		$schema['linked_data']   = array_merge( $schema['linked_data'], $parent_schema['linked_data'] );
-
-		return $schema;
-	}
-
-	/**
-	 * Get the 'organization' schema.
-	 *
-	 * @return array An array with the schema configuration.
-	 *
-	 * @since 3.1.0
-	 */
-	private function get_organization_schema() {
-
-		$schema = array(
-			'label'         => 'Organization',
-			'description'   => 'An organization, including a government or a newspaper.',
-			'parents'       => array( 'thing' ),
-			'css_class'     => 'wl-organization',
-			'uri'           => 'http://schema.org/Organization',
-			'same_as'       => array(
-				'http://rdf.freebase.com/ns/organization.organization',
-				'http://rdf.freebase.com/ns/government.government',
-				'http://schema.org/Newspaper',
-			),
-			'custom_fields' => array(
-				self::FIELD_LEGAL_NAME          => array(
-					'predicate'   => 'http://schema.org/legalName',
-					'type'        => self::DATA_TYPE_STRING,
-					'export_type' => 'xsd:string',
-					'constraints' => '',
-				),
-				self::FIELD_FOUNDER             => array(
-					'predicate'   => 'http://schema.org/founder',
-					'type'        => self::DATA_TYPE_URI,
-					'export_type' => 'http://schema.org/Person',
-					'constraints' => array(
-						'uri_type'    => 'Person',
-						'cardinality' => INF,
-					),
-				),
-				self::FIELD_ADDRESS             => array(
-					'predicate'   => 'http://schema.org/streetAddress',
-					'type'        => self::DATA_TYPE_STRING,
-					'export_type' => 'xsd:string',
-					'constraints' => '',
-					// To build custom metabox.
-					'input_field' => 'address',
-				),
-				self::FIELD_ADDRESS_PO_BOX      => array(
-					'predicate'   => 'http://schema.org/postOfficeBoxNumber',
-					'type'        => self::DATA_TYPE_STRING,
-					'export_type' => 'xsd:string',
-					'constraints' => '',
-					// To build custom metabox.
-					'input_field' => 'address',
-				),
-				self::FIELD_ADDRESS_POSTAL_CODE => array(
-					'predicate'   => 'http://schema.org/postalCode',
-					'type'        => self::DATA_TYPE_STRING,
-					'export_type' => 'xsd:string',
-					'constraints' => '',
-					// To build custom metabox.
-					'input_field' => 'address',
-				),
-				self::FIELD_ADDRESS_LOCALITY    => array(
-					'predicate'   => 'http://schema.org/addressLocality',
-					'type'        => self::DATA_TYPE_STRING,
-					'export_type' => 'xsd:string',
-					'constraints' => '',
-					// To build custom metabox.
-					'input_field' => 'address',
-				),
-				self::FIELD_ADDRESS_REGION      => array(
-					'predicate'   => 'http://schema.org/addressRegion',
-					'type'        => self::DATA_TYPE_STRING,
-					'export_type' => 'xsd:string',
-					'constraints' => '',
-					// To build custom metabox.
-					'input_field' => 'address',
-				),
-				self::FIELD_ADDRESS_COUNTRY     => array(
-					'predicate'   => 'http://schema.org/addressCountry',
-					'type'        => self::DATA_TYPE_STRING,
-					'export_type' => 'xsd:string',
-					'constraints' => '',
-					// To build custom metabox.
-					'input_field' => 'address',
-				),
-				self::FIELD_EMAIL               => array(
-					'predicate'   => 'http://schema.org/email',
-					'type'        => self::DATA_TYPE_STRING,
-					'export_type' => 'xsd:string',
-					'constraints' => '',
-				),
-				self::FIELD_TELEPHONE           => array(
-					'predicate'   => 'http://schema.org/telephone',
-					'type'        => self::DATA_TYPE_STRING,
-					'export_type' => 'xsd:string',
-					'constraints' => '',
-				),
-			),
-			'linked_data'   => array(
-				// ### schema:legalName.
-				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( self::FIELD_LEGAL_NAME ),
-					'http://schema.org/legalName'
-				),
-				// ### schema:founder.
-				$this->rendition_factory->create(
-					$this->storage_factory->post_meta_to_uri( self::FIELD_FOUNDER ),
-					'http://schema.org/founder',
-					self::DATA_TYPE_URI
-				),
-				// ### schema:email.
-				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( self::FIELD_EMAIL ),
-					'http://schema.org/email'
-				),
-				// ### schema:telephone.
-				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( self::FIELD_TELEPHONE ),
-					'http://schema.org/telephone'
-				),
-			),
-			'templates'     => array(
-				'subtitle' => '{{id}}',
-			),
-		);
-
-		// Merge the custom fields with those provided by the thing schema.
-		$parent_schema           = $this->get_thing_schema();
-		$schema['custom_fields'] = array_merge( $schema['custom_fields'], $parent_schema['custom_fields'] );
-		$schema['linked_data']   = array_merge( $schema['linked_data'], $parent_schema['linked_data'] );
-
-		return $schema;
-	}
-
-	/**
-	 * Get the 'person' schema.
-	 *
-	 * @return array An array with the schema configuration.
-	 *
-	 * @since 3.1.0
-	 */
-	private function get_person_schema() {
-
-		$schema = array(
-			'label'         => 'Person',
-			'description'   => 'A person (or a music artist).',
-			'parents'       => array( 'thing' ),
-			'css_class'     => 'wl-person',
-			'uri'           => 'http://schema.org/Person',
-			'same_as'       => array(
-				'http://rdf.freebase.com/ns/people.person',
-				'http://rdf.freebase.com/ns/music.artist',
-				'http://dbpedia.org/class/yago/LivingPeople',
-			),
-			'custom_fields' => array(
-				self::FIELD_KNOWS       => array(
-					'predicate'   => 'http://schema.org/knows',
-					'type'        => self::DATA_TYPE_URI,
-					'export_type' => 'http://schema.org/Person',
-					'constraints' => array(
-						'uri_type'    => 'Person',
-						'cardinality' => INF,
-					),
-				),
-				self::FIELD_BIRTH_DATE  => array(
-					'predicate'   => 'http://schema.org/birthDate',
-					'type'        => self::DATA_TYPE_DATE,
-					'export_type' => 'xsd:date',
-					'constraints' => '',
-				),
-				self::FIELD_BIRTH_PLACE => array(
-					'predicate'   => 'http://schema.org/birthPlace',
-					'type'        => self::DATA_TYPE_URI,
-					'export_type' => 'http://schema.org/Place',
-					'constraints' => array(
-						'uri_type' => 'Place',
-					),
-				),
-				self::FIELD_AFFILIATION => array(
-					'predicate'   => 'http://schema.org/affiliation',
-					'type'        => self::DATA_TYPE_URI,
-					'export_type' => 'http://schema.org/Organization',
-					'constraints' => array(
-						'uri_type'    => array(
-							'Organization',
-							'LocalBusiness',
-						),
-						'cardinality' => INF,
-					),
-				),
-				self::FIELD_EMAIL       => array(
-					'predicate'   => 'http://schema.org/email',
-					'type'        => self::DATA_TYPE_STRING,
-					'export_type' => 'xsd:string',
-					'constraints' => array(
-						'cardinality' => INF,
-					),
-				),
-			),
-			'linked_data'   => array(
-				// ### schema:knows.
-				$this->rendition_factory->create(
-					$this->storage_factory->post_meta_to_uri( self::FIELD_KNOWS ),
-					'http://schema.org/knows',
-					self::DATA_TYPE_URI
-				),
-				// ### schema:birthDate.
-				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( self::FIELD_BIRTH_DATE ),
-					'http://schema.org/birthDate',
-					self::DATA_TYPE_DATE
-				),
-				// ### schema:birthPlace.
-				$this->rendition_factory->create(
-					$this->storage_factory->post_meta_to_uri( self::FIELD_BIRTH_PLACE ),
-					'http://schema.org/birthPlace',
-					self::DATA_TYPE_URI
-				),
-				// ### schema:affiliation.
-				$this->rendition_factory->create(
-					$this->storage_factory->post_meta_to_uri( self::FIELD_AFFILIATION ),
-					'http://schema.org/affiliation',
-					self::DATA_TYPE_URI
-				),
-				// ### schema:email.
-				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( self::FIELD_EMAIL ),
-					'http://schema.org/email'
-				),
-			),
-			'templates'     => array(
-				'subtitle' => '{{id}}',
-			),
-		);
-
-		// Merge the custom fields with those provided by the thing schema.
-		$parent_schema           = $this->get_thing_schema();
-		$schema['custom_fields'] = array_merge( $schema['custom_fields'], $parent_schema['custom_fields'] );
-		$schema['linked_data']   = array_merge( $schema['linked_data'], $parent_schema['linked_data'] );
-
-		return $schema;
-
-	}
-
-	/**
-	 * Get the 'place' schema.
-	 *
-	 * @return array An array with the schema configuration.
-	 *
-	 * @since 3.1.0
-	 */
-	private function get_place_schema() {
-
-		$schema = array(
-			'label'         => 'Place',
-			'description'   => 'A place.',
-			'parents'       => array( 'thing' ),
-			'css_class'     => 'wl-place',
-			'uri'           => 'http://schema.org/Place',
-			'same_as'       => array(
-				'http://rdf.freebase.com/ns/location.location',
-				'http://www.opengis.net/gml/_Feature',
-			),
-			'custom_fields' => array(
-				self::FIELD_GEO_LATITUDE        => array(
-					'predicate'   => 'http://schema.org/latitude',
-					'type'        => self::DATA_TYPE_DOUBLE,
-					'export_type' => 'xsd:double',
-					'constraints' => '',
-					// To build custom metabox.
-					'input_field' => 'coordinates',
-				),
-				self::FIELD_GEO_LONGITUDE       => array(
-					'predicate'   => 'http://schema.org/longitude',
-					'type'        => self::DATA_TYPE_DOUBLE,
-					'export_type' => 'xsd:double',
-					'constraints' => '',
-					// To build custom metabox.
-					'input_field' => 'coordinates',
-				),
-				self::FIELD_ADDRESS             => array(
-					'predicate'   => 'http://schema.org/streetAddress',
-					'type'        => self::DATA_TYPE_STRING,
-					'export_type' => 'xsd:string',
-					'constraints' => '',
-					// To build custom metabox.
-					'input_field' => 'address',
-				),
-				self::FIELD_ADDRESS_PO_BOX      => array(
-					'predicate'   => 'http://schema.org/postOfficeBoxNumber',
-					'type'        => self::DATA_TYPE_STRING,
-					'export_type' => 'xsd:string',
-					'constraints' => '',
-					// To build custom metabox.
-					'input_field' => 'address',
-				),
-				self::FIELD_ADDRESS_POSTAL_CODE => array(
-					'predicate'   => 'http://schema.org/postalCode',
-					'type'        => self::DATA_TYPE_STRING,
-					'export_type' => 'xsd:string',
-					'constraints' => '',
-					// To build custom metabox.
-					'input_field' => 'address',
-				),
-				self::FIELD_ADDRESS_LOCALITY    => array(
-					'predicate'   => 'http://schema.org/addressLocality',
-					'type'        => self::DATA_TYPE_STRING,
-					'export_type' => 'xsd:string',
-					'constraints' => '',
-					// To build custom metabox.
-					'input_field' => 'address',
-				),
-				self::FIELD_ADDRESS_REGION      => array(
-					'predicate'   => 'http://schema.org/addressRegion',
-					'type'        => self::DATA_TYPE_STRING,
-					'export_type' => 'xsd:string',
-					'constraints' => '',
-					// To build custom metabox.
-					'input_field' => 'address',
-				),
-				self::FIELD_ADDRESS_COUNTRY     => array(
-					'predicate'   => 'http://schema.org/addressCountry',
-					'type'        => self::DATA_TYPE_STRING,
-					'export_type' => 'xsd:string',
-					'constraints' => '',
-					// To build custom metabox.
-					'input_field' => 'address',
-				),
-			),
-			'linked_data'   => array(
-				$this->rendition_factory->create_address(
-					$this->storage_factory,
-					$this->language_code
-				),
-			),
-			'templates'     => array(
-				'subtitle' => '{{id}}',
-			),
-		);
-
-		// Merge the custom fields with those provided by the thing schema.
-		$parent_schema           = $this->get_thing_schema();
-		$schema['custom_fields'] = array_merge( $schema['custom_fields'], $parent_schema['custom_fields'] );
-		$schema['linked_data']   = array_merge( $schema['linked_data'], $parent_schema['linked_data'] );
-
-		return $schema;
-	}
-
-	/**
-	 * Get the 'local business' schema.
-	 *
-	 * @return array An array with the schema configuration.
-	 *
-	 * @since 3.1.0
-	 */
-	private function get_local_business_schema() {
-
-		$schema = array(
-			'label'         => 'LocalBusiness',
-			'description'   => 'A local business.',
-			'parents'       => array( 'place', 'organization' ),
-			'css_class'     => 'wl-local-business',
-			'uri'           => 'http://schema.org/LocalBusiness',
-			'same_as'       => array(
-				'http://rdf.freebase.com/ns/business/business_location',
-				'https://schema.org/Store',
-			),
-			'custom_fields' => array(),
-			'linked_data'   => array(),
-			'templates'     => array(
-				'subtitle' => '{{id}}',
-			),
-		);
-
-		// Merge the custom fields with those provided by the place and organization schema.
-		$place_schema            = $this->get_place_schema();
-		$organization_schema     = $this->get_organization_schema();
-		$schema['custom_fields'] = array_merge( $schema['custom_fields'], $place_schema['custom_fields'], $organization_schema['custom_fields'] );
-		$schema['linked_data']   = array_merge( $schema['linked_data'], $place_schema['linked_data'], $organization_schema['linked_data'] );
-
-		return $schema;
-	}
-
-	/**
-	 * Get the 'recipe' schema.
-	 *
-	 * @return array An array with the schema configuration.
-	 *
-	 * @since 3.14.0
-	 */
-	private function get_recipe_schema() {
-
-		$schema = array(
-			'label'         => 'Recipe',
-			'description'   => 'A Recipe.',
-			'parents'       => array( 'CreativeWork' ),
-			'css_class'     => 'wl-recipe',
-			'uri'           => 'http://schema.org/Recipe',
-			'same_as'       => array(),
-			'templates'     => array(
-				'subtitle' => '{{id}}',
-			),
-			'custom_fields' => array(
-				self::FIELD_RECIPE_CUISINE          => array(
-					'predicate'   => 'http://schema.org/recipeCuisine',
-					'type'        => self::DATA_TYPE_STRING,
-					'export_type' => 'xsd:string',
-					'constraints' => '',
-					'metabox'     => array(
-						'label' => __( 'Recipe cuisine', 'wordlift' ),
-					),
-				),
-				self::FIELD_RECIPE_INGREDIENT       => array(
-					'predicate'   => 'http://schema.org/recipeIngredient',
-					'type'        => self::DATA_TYPE_STRING,
-					'export_type' => 'xsd:string',
-					'constraints' => array(
-						'cardinality' => INF,
-					),
-					'metabox'     => array(
-						'label' => __( 'Recipe ingredient', 'wordlift' ),
-					),
-				),
-				self::FIELD_RECIPE_INSTRUCTIONS     => array(
-					'predicate'   => 'http://schema.org/recipeInstructions',
-					'type'        => self::DATA_TYPE_MULTILINE,
-					'export_type' => 'xsd:string',
-					'constraints' => '',
-					'metabox'     => array(
-						'class' => 'Wordlift_Metabox_Field_Multiline',
-						'label' => __( 'Recipe instructions', 'wordlift' ),
-					),
-				),
-				self::FIELD_RECIPE_YIELD            => array(
-					'predicate'   => 'http://schema.org/recipeYield',
-					'type'        => self::DATA_TYPE_STRING,
-					'export_type' => 'xsd:string',
-					'constraints' => '',
-					'metabox'     => array(
-						'label' => __( 'Recipe number of servings', 'wordlift' ),
-					),
-				),
-				self::FIELD_RECIPE_INGREDIENT       => array(
-					'predicate'   => 'http://schema.org/recipeIngredient',
-					'type'        => self::DATA_TYPE_STRING,
-					'export_type' => 'xsd:string',
-					'constraints' => array(
-						'cardinality' => INF,
-					),
-					'metabox'     => array(
-						'label' => __( 'Recipe ingredient', 'wordlift' ),
-					),
-				),
-				self::FIELD_NUTRITION_INFO_CALORIES => array(
-					'predicate'   => 'http://schema.org/calories',
-					'type'        => self::DATA_TYPE_STRING,
-					'export_type' => 'xsd:string',
-					'constraints' => '',
-					'metabox'     => array(
-						'label' => __( 'Calories (e.g. 240 calories)', 'wordlift' ),
-					),
-				),
-				self::FIELD_PREP_TIME               => array(
-					'predicate'   => 'http://schema.org/prepTime',
-					'type'        => self::DATA_TYPE_DURATION,
-					'export_type' => 'xsd:time',
-					'constraints' => '',
-					'metabox'     => array(
-						'class' => 'Wordlift_Metabox_Field_Duration',
-						'label' => __( 'Recipe preparation time (e.g. 1:30)', 'wordlift' ),
-					),
-				),
-				self::FIELD_COOK_TIME               => array(
-					'predicate'   => 'http://schema.org/cookTime',
-					'type'        => self::DATA_TYPE_DURATION,
-					'export_type' => 'xsd:time',
-					'constraints' => '',
-					'metabox'     => array(
-						'class' => 'Wordlift_Metabox_Field_Duration',
-						'label' => __( 'Recipe cook time (e.g. 1:30)', 'wordlift' ),
-					),
-				),
-				self::FIELD_TOTAL_TIME              => array(
-					'predicate'   => 'http://schema.org/totalTime',
-					'type'        => self::DATA_TYPE_DURATION,
-					'export_type' => 'xsd:time',
-					'constraints' => '',
-					'metabox'     => array(
-						'class' => 'Wordlift_Metabox_Field_Duration',
-						'label' => __( 'Recipe total time (e.g. 1:30)', 'wordlift' ),
-					),
-				),
-			),
-			'linked_data'   => array(
-				// ### schema:recipeCuisine.
-				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( self::FIELD_RECIPE_CUISINE ),
-					'http://schema.org/recipeCuisine'
-				),
-				// ### schema:recipeIngredient.
-				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( self::FIELD_RECIPE_INGREDIENT ),
-					'http://schema.org/recipeIngredient'
-				),
-				// ### schema:recipeInstructions.
-				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( self::FIELD_RECIPE_INSTRUCTIONS ),
-					'http://schema.org/recipeInstructions'
-				),
-				// ### schema:recipeYield.
-				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( self::FIELD_RECIPE_YIELD ),
-					'http://schema.org/recipeYield'
-				),
-				// ### schema:prepTime.
-				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( self::FIELD_PREP_TIME ),
-					'http://schema.org/prepTime',
-					self::DATA_TYPE_DURATION
-				),
-				// ### schema:cookTime.
-				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( self::FIELD_COOK_TIME ),
-					'http://schema.org/cookTime',
-					self::DATA_TYPE_DURATION
-				),
-				// ### schema:totalTime.
-				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( self::FIELD_TOTAL_TIME ),
-					'http://schema.org/totalTime',
-					self::DATA_TYPE_DURATION
-				),
-			),
-		);
-
-		// Merge the custom fields with those provided by the parent schema.
-		$parent_schema           = $this->get_creative_work_schema();
-		$schema['custom_fields'] = array_merge( $schema['custom_fields'], $parent_schema['custom_fields'] );
-		$schema['linked_data']   = array_merge( $schema['linked_data'], $parent_schema['linked_data'] );
-
-		return $schema;
-	}
-
-	/**
-	 * Get the 'offer' schema.
-	 *
-	 * @return array An array with the schema configuration.
-	 *
-	 * @since 3.18.0
-	 */
-	private function get_offer_schema() {
-
-		$schema = array(
-			'label'         => 'Offer',
-			'description'   => 'An offer. ',
-			'parents'       => array( 'thing' ),
-			'css_class'     => 'wl-offer',
-			'uri'           => self::SCHEMA_OFFER_TYPE,
-			'same_as'       => array(),
-			'templates'     => array(
-				'subtitle' => '{{id}}',
-			),
-			'custom_fields' => array(
-				self::FIELD_AVAILABILITY        => array(
-					'predicate'   => 'http://schema.org/availability',
-					'type'        => self::DATA_TYPE_STRING,
-					'export_type' => 'xsd:string',
-					'metabox'     => array(
-						'class' => 'Wordlift_Metabox_Field_Select',
-					),
-					'options'     => array(
-						'Discontinued'        => esc_html__( 'Discontinued', 'wordlift' ),
-						'InStock'             => esc_html__( 'In Stock', 'wordlift' ),
-						'InStoreOnly'         => esc_html__( 'In Store Only', 'wordlift' ),
-						'LimitedAvailability' => esc_html__( 'Limited Availability', 'wordlift' ),
-						'OnlineOnly'          => esc_html__( 'Online Only', 'wordlift' ),
-						'OutOfStock'          => esc_html__( 'Out of Stock', 'wordlift' ),
-						'PreOrder'            => esc_html__( 'Pre Order', 'wordlift' ),
-						'PreSale'             => esc_html__( 'Pre Sale', 'wordlift' ),
-						'SoldOut'             => esc_html__( 'Sold Out', 'wordlift' ),
-					),
-				),
-				self::FIELD_PRICE               => array(
-					'predicate'   => 'http://schema.org/price',
-					'type'        => self::DATA_TYPE_STRING,
-					'export_type' => 'xsd:integer',
-					'metabox'     => array(
-						'class' => 'Wordlift_Metabox_Field_Integer',
-					),
-				),
-				self::FIELD_PRICE_CURRENCY      => array(
-					'predicate'   => 'http://schema.org/priceCurrency',
-					'type'        => self::DATA_TYPE_STRING,
-					'export_type' => 'xsd:string',
-				),
-				self::FIELD_AVAILABILITY_STARTS => array(
-					'predicate'   => 'http://schema.org/availabilityStarts',
-					'type'        => self::DATA_TYPE_DATE,
-					'export_type' => 'xsd:dateTime',
-				),
-				self::FIELD_AVAILABILITY_ENDS   => array(
-					'predicate'   => 'http://schema.org/availabilityEnds',
-					'type'        => self::DATA_TYPE_DATE,
-					'export_type' => 'xsd:dateTime',
-				),
-				self::FIELD_INVENTORY_LEVEL     => array(
-					'predicate'   => 'http://schema.org/inventoryLevel',
-					'type'        => self::DATA_TYPE_STRING,
-					'export_type' => 'xsd:integer',
-					'metabox'     => array(
-						'class' => 'Wordlift_Metabox_Field_Integer',
-					),
-				),
-				self::FIELD_VALID_FROM          => array(
-					'predicate'   => 'http://schema.org/validFrom',
-					'type'        => self::DATA_TYPE_DATE,
-					'export_type' => 'xsd:dateTime',
-				),
-				self::FIELD_PRICE_VALID_UNTIL   => array(
-					'predicate'   => 'http://schema.org/priceValidUntil',
-					'type'        => self::DATA_TYPE_DATE,
-					'export_type' => 'xsd:dateTime',
-				),
-				self::FIELD_ITEM_OFFERED        => array(
-					'predicate'   => 'http://schema.org/itemOffered',
-					'type'        => self::DATA_TYPE_URI,
-					'export_type' => 'http://schema.org/Thing',
-					'constraints' => array(
-						'uri_type'    => array(
-							'Event',
-							'Thing',
-						),
-						'cardinality' => INF,
-					),
-				),
-			),
-			'linked_data'   => array(
-				// ### schema:availability.
-				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( self::FIELD_AVAILABILITY ),
-					'http://schema.org/availability',
-					null
-				),
-				// ### schema:availabilityStarts.
-				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( self::FIELD_AVAILABILITY_STARTS ),
-					'http://schema.org/availabilityStarts',
-					self::DATA_TYPE_DATE_TIME
-				),
-				// ### schema:availabilityEnds.
-				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( self::FIELD_AVAILABILITY_ENDS ),
-					'http://schema.org/availabilityEnds',
-					self::DATA_TYPE_DATE_TIME
-				),
-				// ### schema:inventoryLevel.
-				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( self::FIELD_INVENTORY_LEVEL ),
-					'http://schema.org/inventoryLevel',
-					self::DATA_TYPE_INTEGER
-				),
-				// ### schema:price.
-				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( self::FIELD_PRICE ),
-					'http://schema.org/price',
-					self::DATA_TYPE_INTEGER
-				),
-				// ### schema:priceCurrency.
-				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( self::FIELD_PRICE_CURRENCY ),
-					'http://schema.org/priceCurrency',
-					null
-				),
-				// ### schema:validFrom.
-				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( self::FIELD_VALID_FROM ),
-					'http://schema.org/validFrom',
-					null
-				),
-				// ### schema:priceValidUntil.
-				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( self::FIELD_PRICE_VALID_UNTIL ),
-					'http://schema.org/priceValidUntil',
-					null
-				),
-				// ### schema:itemOffered.
-				$this->rendition_factory->create(
-					$this->storage_factory->post_meta_to_uri( self::FIELD_ITEM_OFFERED ),
-					'http://schema.org/itemOffered',
-					self::DATA_TYPE_URI
-				),
-			),
-		);
-
-		// Merge the custom fields with those provided by the thing schema.
-		$parent_schema           = $this->get_thing_schema();
-		$schema['custom_fields'] = array_merge( $schema['custom_fields'], $parent_schema['custom_fields'] );
-		$schema['linked_data']   = array_merge( $schema['linked_data'], $parent_schema['linked_data'] );
-
-		return $schema;
-	}
-
-	/**
-	 * Get the 'article' schema.
-	 *
-	 * @return array An array with the schema configuration.
-	 *
-	 * @since 3.15.0
-	 */
-	private function get_article_schema() {
-
-		$schema = array(
-			'label'         => 'Article',
-			'description'   => 'An Article.',
-			'parents'       => array(),
-			'css_class'     => 'wl-article',
-			'uri'           => 'http://schema.org/Article',
-			'same_as'       => array(),
-			'templates'     => array(
-				'subtitle' => '{{id}}',
-			),
-			'custom_fields' => array(),
-			'linked_data'   => array(
-				// ### schema:headline.
-				$this->rendition_factory->create(
-					$this->storage_factory->post_title(),
-					'http://schema.org/headline',
-					null,
-					$this->language_code
-				),
-				// ### schema:url.
-				$this->rendition_factory->create(
-					$this->storage_factory->url_property(),
-					Wordlift_Query_Builder::SCHEMA_URL_URI,
-					self::DATA_TYPE_URI
-				),
-				// ### rdf:type.
-				$this->rendition_factory->create(
-					$this->storage_factory->schema_class(),
-					Wordlift_Query_Builder::RDFS_TYPE_URI,
-					self::DATA_TYPE_URI
-				),
-				// ### dcterms:references.
-				$this->rendition_factory->create(
-					$this->storage_factory->relations(),
-					Wordlift_Query_Builder::DCTERMS_REFERENCES_URI,
-					self::DATA_TYPE_URI,
-					$this->language_code
-				),
-			),
-		);
-
-		return $schema;
-	}
+    /**
+     * The 'location created' field name.
+     *
+     * @since 3.5.0
+     */
+    const FIELD_LOCATION_CREATED = 'wl_location_created';
+
+    /**
+     * The 'topic' field name.
+     *
+     * @since 3.5.0
+     */
+    const FIELD_TOPIC = 'wl_topic';
+
+    /**
+     * The 'author' field name.
+     *
+     * @since 3.1.0
+     */
+    const FIELD_AUTHOR = 'wl_author';
+
+    /**
+     * The 'same as' field name.
+     *
+     * @since 3.1.0
+     */
+    const FIELD_SAME_AS = 'entity_same_as';
+
+    /**
+     * The 'date start' field name.
+     *
+     * @since 3.1.0
+     */
+    const FIELD_DATE_START = 'wl_cal_date_start';
+
+    /**
+     * The 'date end' field name.
+     *
+     * @since 3.1.0
+     */
+    const FIELD_DATE_END = 'wl_cal_date_end';
+
+    /**
+     * The 'location' field name.
+     *
+     * @since 3.1.0
+     */
+    const FIELD_LOCATION = 'wl_location';
+
+    /**
+     * The 'founder' field name.
+     *
+     * @since 3.1.0
+     */
+    const FIELD_FOUNDER = 'wl_founder';
+
+    /**
+     * The 'knows' field name.
+     *
+     * @since 3.1.0
+     */
+    const FIELD_KNOWS = 'wl_knows';
+
+    /**
+     * The 'birth date' field name.
+     *
+     * @since 3.1.0
+     */
+    const FIELD_BIRTH_DATE = 'wl_birth_date';
+
+    /**
+     * The 'birth place' field name.
+     *
+     * @since 3.1.0
+     */
+    const FIELD_BIRTH_PLACE = 'wl_birth_place';
+
+    /**
+     * The 'latitude' field name.
+     *
+     * @since 3.1.0
+     */
+    const FIELD_GEO_LATITUDE = 'wl_geo_latitude';
+
+    /**
+     * The 'longitude' field name.
+     *
+     * @since 3.1.0
+     */
+    const FIELD_GEO_LONGITUDE = 'wl_geo_longitude';
+
+    /**
+     * The 'streetAddress' field name.
+     *
+     * @since 3.1.0
+     */
+    const FIELD_ADDRESS = 'wl_address';
+
+    /**
+     * The 'postOfficeBoxNumber' field name.
+     *
+     * @since 3.3.0
+     */
+    const FIELD_ADDRESS_PO_BOX = 'wl_address_post_office_box';
+
+    /**
+     * The 'postalCode' field name.
+     *
+     * @since 3.3.0
+     */
+    const FIELD_ADDRESS_POSTAL_CODE = 'wl_address_postal_code';
+
+    /**
+     * The 'addressLocality' field name.
+     *
+     * @since 3.3.0
+     */
+    const FIELD_ADDRESS_LOCALITY = 'wl_address_locality';
+    /**
+     * The 'addressRegion' field name.
+     *
+     * @since 3.3.0
+     */
+    const FIELD_ADDRESS_REGION = 'wl_address_region';
+
+    /**
+     * The 'addressCountry' field name.
+     *
+     * @since 3.3.0
+     */
+    const FIELD_ADDRESS_COUNTRY = 'wl_address_country';
+
+    /**
+     * The 'entity type' field name.
+     *
+     * @since 3.1.0
+     */
+    const FIELD_ENTITY_TYPE = 'wl_entity_type_uri';
+
+    /**
+     * The 'email' field name.
+     *
+     * @since 3.2.0
+     */
+    const FIELD_EMAIL = 'wl_email';
+
+    /**
+     * The 'affiliation' field name.
+     *
+     * @since 3.2.0
+     */
+    const FIELD_AFFILIATION = 'wl_affiliation';
+
+    /**
+     * The 'telephone' field name.
+     *
+     * @since 3.8.0
+     */
+    const FIELD_TELEPHONE = 'wl_schema_telephone';
+
+    /**
+     * The 'legalName' field name.
+     *
+     * @since 3.12.0
+     */
+    const FIELD_LEGAL_NAME = 'wl_schema_legal_name';
+
+    /**
+     * The 'recipeCuisine' field name.
+     *
+     * @since 3.14.0
+     */
+    const FIELD_RECIPE_CUISINE = 'wl_schema_recipe_cuisine';
+
+    /**
+     * The 'recipeIngredient' field name.
+     *
+     * @since 3.14.0
+     */
+    const FIELD_RECIPE_INGREDIENT = 'wl_schema_recipe_ingredient';
+
+    /**
+     * The 'calories' field name.
+     *
+     * @since 3.14.0
+     */
+    const FIELD_NUTRITION_INFO_CALORIES = 'wl_schema_nutrition_information_calories';
+
+    /**
+     * The 'recipeInstructions' field name.
+     *
+     * @since 3.14.0
+     */
+    const FIELD_RECIPE_INSTRUCTIONS = 'wl_schema_recipe_instructions';
+
+    /**
+     * The 'recipeYield' field name.
+     *
+     * @since 3.14.0
+     */
+    const FIELD_RECIPE_YIELD = 'wl_schema_recipe_yield';
+
+    /**
+     * The 'prepTime' field name.
+     *
+     * @since 3.14.0
+     */
+    const FIELD_PREP_TIME = 'wl_schema_prep_time';
+
+    /**
+     * The 'cookTime' field name.
+     *
+     * @since 3.14.0
+     */
+    const FIELD_COOK_TIME = 'wl_schema_cook_time';
+
+    /**
+     * The 'totalTime' field name.
+     *
+     * @since 3.14.0
+     */
+    const FIELD_TOTAL_TIME = 'wl_schema_total_time';
+
+    /**
+     * The 'performer' field name.
+     *
+     * @since 3.18.0
+     */
+    const FIELD_PERFORMER = 'wl_schema_performer';
+
+    /**
+     * The 'offers' field name.
+     *
+     * @since 3.18.0
+     */
+    const FIELD_OFFERS = 'wl_schema_offers';
+
+    /**
+     * The 'availablity' field name.
+     *
+     * @since 3.18.0
+     */
+    const FIELD_AVAILABILITY = 'wl_schema_availability';
+
+    /**
+     * The 'inventoryLevel' field name.
+     *
+     * @since 3.18.0
+     */
+    const FIELD_INVENTORY_LEVEL = 'wl_schema_inventory_level';
+
+    /**
+     * The 'price' field name.
+     *
+     * @since 3.18.0
+     */
+    const FIELD_PRICE = 'wl_schema_price';
+
+    /**
+     * The 'priceCurrency' field name.
+     *
+     * @since 3.18.0
+     */
+    const FIELD_PRICE_CURRENCY = 'wl_schema_price_currency';
+
+    /**
+     * The 'availabilityStarts' field name.
+     *
+     * @since 3.18.0
+     */
+    const FIELD_AVAILABILITY_STARTS = 'wl_schema_availability_starts';
+
+    /**
+     * The 'availabilityEnds' field name.
+     *
+     * @since 3.18.0
+     */
+    const FIELD_AVAILABILITY_ENDS = 'wl_schema_availability_ends';
+
+    /**
+     * The 'validFrom' field name.
+     *
+     * @since 3.18.0
+     */
+    const FIELD_VALID_FROM = 'wl_schema_valid_from';
+
+    /**
+     * The 'priceValidUntil' field name.
+     *
+     * @since 3.18.0
+     */
+    const FIELD_PRICE_VALID_UNTIL = 'wl_schema_valid_until';
+
+    /**
+     * The 'itemOffered' field name.
+     *
+     * @since 3.18.0
+     */
+    const FIELD_ITEM_OFFERED = 'wl_schema_item_offered';
+
+    /**
+     * The 'URI' data type name.
+     *
+     * @since 3.1.0
+     */
+    const DATA_TYPE_URI = 'uri';
+
+    /**
+     * The 'date' data type name.
+     *
+     * @since 3.1.0
+     */
+    const DATA_TYPE_DATE = 'date';
+
+    /**
+     * The 'dateTime' data type name.
+     *
+     * @since 3.15.0
+     */
+    const DATA_TYPE_DATE_TIME = 'dateTime';
+
+    /**
+     * The 'time' data type name.
+     *
+     * @since 3.14.0
+     */
+    const DATA_TYPE_DURATION = 'duration';
+
+    /**
+     * The 'double' data type name.
+     *
+     * @since 3.1.0
+     */
+    const DATA_TYPE_DOUBLE = 'double';
+
+    /**
+     * The 'string' data type name.
+     *
+     * @since 3.1.0
+     */
+    const DATA_TYPE_STRING = 'string';
+
+    /**
+     * The multiline text data type name.
+     *
+     * @since 3.14.0
+     */
+    const DATA_TYPE_MULTILINE = 'multiline';
+
+    /**
+     * The 'integer' data type name.
+     *
+     * @since 3.1.0
+     */
+    const DATA_TYPE_INTEGER = 'int';
+
+    /**
+     * The 'boolean' data type name.
+     *
+     * @since 3.1.0
+     */
+    const DATA_TYPE_BOOLEAN = 'bool';
+
+    /**
+     * The schema.org Event type URI.
+     *
+     * @since 3.1.0
+     */
+    const SCHEMA_EVENT_TYPE = 'http://schema.org/Event';
+
+    /**
+     * The schema.org Offer type URI.
+     *
+     * @since 3.18.0
+     */
+    const SCHEMA_OFFER_TYPE = 'http://schema.org/Offer';
+
+    /**
+     * The Schema service singleton instance.
+     *
+     * @since  3.1.0
+     * @access private
+     * @var \Wordlift_Schema_Service $instance The Schema service singleton instance.
+     */
+    private static $instance;
+
+    /**
+     * WordLift's schema.
+     *
+     * @since  3.1.0
+     * @access private
+     * @var array $schema WordLift's schema.
+     */
+    private $schema;
+
+    /**
+     * The Log service.
+     *
+     * @since  3.1.0
+     * @access private
+     * @var \Wordlift_Log_Service $log The Log service.
+     */
+    private $log;
+
+    /**
+     * The {@link Wordlift_Post_Property_Storage_Factory} instance.
+     *
+     * @since  3.15.0
+     * @access private
+     * @var \Wordlift_Storage_Factory $storage_factory The {@link Wordlift_Post_Property_Storage_Factory} instance.
+     */
+    private $storage_factory;
+
+    /**
+     * The {@link Wordlift_Sparql_Tuple_Rendition_Factory} instance.
+     *
+     * @since  3.15.0
+     * @access private
+     * @var \Wordlift_Sparql_Tuple_Rendition_Factory $rendition_factory The {@link Wordlift_Sparql_Tuple_Rendition_Factory} instance.
+     */
+    private $rendition_factory;
+
+    /**
+     * The {@link Wordlift_Configuration_Service} instance.
+     *
+     * @since  3.15.0
+     * @access private
+     * @var \Wordlift_Configuration_Service $configuration_service The {@link Wordlift_Configuration_Service} instance.
+     */
+    private $configuration_service;
+
+    /**
+     * The web site configured language code.
+     *
+     * @since  3.15.0
+     * @access private
+     * @var string $language_code The web site configured language code.
+     */
+    private $language_code;
+
+    /**
+     * Wordlift_Schema_Service constructor.
+     *
+     * @since 3.1.0
+     *
+     * @param \Wordlift_Storage_Factory                $storage_factory       The {@link Wordlift_Post_Property_Storage_Factory} instance.
+     * @param \Wordlift_Sparql_Tuple_Rendition_Factory $rendition_factory     The {@link Wordlift_Sparql_Tuple_Rendition_Factory} instance.
+     * @param \Wordlift_Configuration_Service          $configuration_service The {@link Wordlift_Configuration_Service} instance.
+     */
+    public function __construct( $storage_factory, $rendition_factory, $configuration_service ) {
+
+        $this->log = Wordlift_Log_Service::get_logger( 'Wordlift_Schema_Service' );
+
+        $this->storage_factory       = $storage_factory;
+        $this->rendition_factory     = $rendition_factory;
+        $this->configuration_service = $configuration_service;
+        $this->language_code         = $this->configuration_service->get_language_code();
+
+        // Set the taxonomy data.
+        // Note: parent types must be defined before child types.
+        $this->schema = array(
+            'article'       => $this->get_article_schema(),
+            'thing'         => $this->get_thing_schema(),
+            'creative-work' => $this->get_creative_work_schema(),
+            'event'         => $this->get_event_schema(),
+            'organization'  => $this->get_organization_schema(),
+            'person'        => $this->get_person_schema(),
+            'place'         => $this->get_place_schema(),
+            'localbusiness' => $this->get_local_business_schema(),
+            'recipe'        => $this->get_recipe_schema(),
+            'web-page'      => $this->get_web_page_schema(),
+            'offer'         => $this->get_offer_schema(),
+        );
+
+        // Create a singleton instance of the Schema service, useful to provide static functions to global functions.
+        self::$instance = $this;
+
+    }
+
+    /**
+     * Get a reference to the Schema service.
+     *
+     * @since 3.1.0
+     *
+     * @return Wordlift_Schema_Service A reference to the Schema service.
+     */
+    public static function get_instance() {
+
+        return self::$instance;
+    }
+
+    /**
+     * Get the properties for a field with the specified key. The key is used as
+     * meta key when the field's value is stored in WordPress meta data table.
+     *
+     * @since 3.6.0
+     *
+     * @param string $key The field's key.
+     *
+     * @return null|array An array of field's properties or null if the field is not found.
+     */
+    public function get_field( $key ) {
+
+        // Parse each schema's fields until we find the one we're looking for, then
+        // return its properties.
+        foreach ( $this->schema as $_ => $schema ) {
+
+            if ( ! isset( $schema['custom_fields'] ) ) {
+                break;
+            }
+
+            foreach ( $schema['custom_fields'] as $field => $props ) {
+                if ( $key === $field ) {
+                    return $props;
+                }
+            }
+        }
+
+        return null;
+    }
+
+    /**
+     * Get all renditions for each WordLift's schema.
+     *
+     * @since 3.18.0
+     *
+     * @return array An array with the schema renditions.
+     */
+    public function get_renditions() {
+        // Get the custom fields.
+        $renditions = array_reduce(
+            $this->schema,
+            function ( $carry, $item ) {
+                return array_merge( $carry, $item['linked_data'] );
+            },
+            array()
+        );
+
+        // Return the schemas.
+        return $renditions;
+    }
+
+    /**
+     * Get the WordLift's schema.
+     *
+     * @param string $name The schema name.
+     *
+     * @return array|null An array with the schema configuration or NULL if the schema is not found.
+     *
+     * @since 3.1.0
+     */
+    public function get_schema( $name ) {
+        // Check if the schema exists and, if not, return NULL.
+        if ( ! isset( $this->schema[ $name ] ) ) {
+            return null;
+        }
+
+        // Return the requested schema.
+        return $this->schema[ $name ];
+    }
+
+    /**
+     * Get the WordLift's schema trough schema type uri.
+     *
+     * @param string $uri The schema uri.
+     *
+     * @return array|null An array with the schema configuration or NULL if the schema is not found.
+     *
+     * @since 3.3.0
+     */
+    public function get_schema_by_uri( $uri ) {
+
+        foreach ( $this->schema as $name => $schema ) {
+            if ( $schema['uri'] === $uri ) {
+                return $schema;
+            }
+        }
+
+        return null;
+    }
+
+    /**
+     * Get the 'thing' schema.
+     *
+     * @return array An array with the schema configuration.
+     *
+     * @since 3.1.0
+     */
+    private function get_thing_schema() {
+
+        return array(
+            'css_class'     => 'wl-thing',
+            'uri'           => 'http://schema.org/Thing',
+            'same_as'       => array( '*' ),
+            // set as default.
+            'custom_fields' => array(
+                self::FIELD_SAME_AS                            => array(
+                    'predicate'   => 'http://schema.org/sameAs',
+                    'type'        => self::DATA_TYPE_URI,
+                    'export_type' => 'http://schema.org/Thing',
+                    'constraints' => array(
+                        'cardinality' => INF,
+                    ),
+                    // We need a custom metabox.
+                    'input_field' => 'sameas',
+                ),
+                // Add the schema:url property.
+                Wordlift_Schema_Url_Property_Service::META_KEY => Wordlift_Schema_Url_Property_Service::get_instance()
+                                                                                                        ->get_compat_definition(),
+            ),
+            // {{sameAs}} not present in the microdata template,
+            // because it is treated separately in *wl_content_embed_item_microdata*
+            'templates'     => array(
+                'subtitle' => '{{id}}',
+            ),
+            'linked_data'   => array(
+                // ### Title to rdfs:label.
+                $this->rendition_factory->create(
+                    $this->storage_factory->post_title(),
+                    Wordlift_Query_Builder::RDFS_LABEL_URI,
+                    null,
+                    $this->language_code
+                ),
+                // ### Title to dct:title.
+                $this->rendition_factory->create(
+                    $this->storage_factory->post_title(),
+                    'http://purl.org/dc/terms/title',
+                    null,
+                    $this->language_code
+                ),
+                // ### Alternative title to rdfs:label.
+                $this->rendition_factory->create(
+                    $this->storage_factory->post_meta( Wordlift_Entity_Service::ALTERNATIVE_LABEL_META_KEY ),
+                    Wordlift_Query_Builder::RDFS_LABEL_URI,
+                    null,
+                    $this->language_code
+                ),
+                // ### Alternative title to dct:title.
+                $this->rendition_factory->create(
+                    $this->storage_factory->post_meta( Wordlift_Entity_Service::ALTERNATIVE_LABEL_META_KEY ),
+                    'http://purl.org/dc/terms/title',
+                    null,
+                    $this->language_code
+                ),
+                // ### Title to schema:name.
+                $this->rendition_factory->create(
+                    $this->storage_factory->post_title(),
+                    'http://schema.org/name',
+                    null,
+                    $this->language_code
+                ),
+                // ### Alternative title to schema:alterName.
+                $this->rendition_factory->create(
+                    $this->storage_factory->post_meta( Wordlift_Entity_Service::ALTERNATIVE_LABEL_META_KEY ),
+                    'http://schema.org/alternateName',
+                    null,
+                    $this->language_code
+                ),
+                // ### schema:url.
+                $this->rendition_factory->create(
+                    $this->storage_factory->url_property(),
+                    Wordlift_Query_Builder::SCHEMA_URL_URI,
+                    self::DATA_TYPE_URI
+                ),
+                // ### schema:description.
+                $this->rendition_factory->create(
+                    $this->storage_factory->post_description_no_tags_no_shortcodes(),
+                    'http://schema.org/description',
+                    null,
+                    $this->language_code
+                ),
+                // ### owl:sameAs.
+                $this->rendition_factory->create(
+                    $this->storage_factory->post_meta( self::FIELD_SAME_AS ),
+                    'http://www.w3.org/2002/07/owl#sameAs',
+                    self::DATA_TYPE_URI
+                ),
+                // ### rdf:type.
+                $this->rendition_factory->create(
+                    $this->storage_factory->schema_class(),
+                    Wordlift_Query_Builder::RDFS_TYPE_URI,
+                    self::DATA_TYPE_URI
+                ),
+                // ### schema:image.
+                $this->rendition_factory->create(
+                    $this->storage_factory->post_images(),
+                    Wordlift_Query_Builder::SCHEMA_IMAGE_URI,
+                    self::DATA_TYPE_URI
+                ),
+                // ### dct:relation.
+                $this->rendition_factory->create(
+                    $this->storage_factory->relations(),
+                    Wordlift_Query_Builder::DCTERMS_RELATION_URI,
+                    self::DATA_TYPE_URI
+                ),
+            ),
+        );
+
+    }
+
+    /**
+     * Get the 'web-page' schema.
+     *
+     * @return array An array with the schema configuration.
+     *
+     * @since 3.18.0
+     */
+    private function get_web_page_schema() {
+
+        return array(
+            'css_class'   => 'wl-webpage',
+            'uri'         => 'http://schema.org/WebPage',
+            'linked_data' => array(
+                // ### schema:headline.
+                $this->rendition_factory->create(
+                    $this->storage_factory->post_title(),
+                    'http://schema.org/headline',
+                    null,
+                    $this->language_code
+                ),
+                // ### schema:url.
+                $this->rendition_factory->create(
+                    $this->storage_factory->url_property(),
+                    Wordlift_Query_Builder::SCHEMA_URL_URI,
+                    self::DATA_TYPE_URI
+                ),
+                // ### rdf:type.
+                $this->rendition_factory->create(
+                    $this->storage_factory->schema_class(),
+                    Wordlift_Query_Builder::RDFS_TYPE_URI,
+                    self::DATA_TYPE_URI
+                ),
+                // ### dcterms:references.
+                $this->rendition_factory->create(
+                    $this->storage_factory->relations(),
+                    Wordlift_Query_Builder::DCTERMS_REFERENCES_URI,
+                    self::DATA_TYPE_URI,
+                    $this->language_code
+                ),
+            ),
+        );
+
+    }
+
+    /**
+     * Get the 'creative work' schema.
+     *
+     * @return array An array with the schema configuration.
+     *
+     * @since 3.1.0
+     */
+    private function get_creative_work_schema() {
+
+        $schema = array(
+            'label'         => 'CreativeWork',
+            'description'   => 'A creative work (or a Music Album).',
+            'parents'       => array( 'thing' ),
+            // Give term slug as parent.
+            'css_class'     => 'wl-creative-work',
+            'uri'           => 'http://schema.org/CreativeWork',
+            'same_as'       => array(
+                'http://schema.org/MusicAlbum',
+                'http://schema.org/Product',
+            ),
+            'custom_fields' => array(
+                self::FIELD_AUTHOR => array(
+                    'predicate'   => 'http://schema.org/author',
+                    'type'        => self::DATA_TYPE_URI,
+                    'export_type' => 'http://schema.org/Person',
+                    'constraints' => array(
+                        'uri_type'    => array( 'Person', 'Organization' ),
+                        'cardinality' => INF,
+                    ),
+                ),
+            ),
+            'linked_data'   => array(
+                // ### schema:author.
+                $this->rendition_factory->create(
+                    $this->storage_factory->author_uri(),
+                    Wordlift_Query_Builder::SCHEMA_AUTHOR_URI,
+                    self::DATA_TYPE_URI
+                ),
+            ),
+            'templates'     => array(
+                'subtitle' => '{{id}}',
+            ),
+        );
+
+        // Merge the custom fields with those provided by the thing schema.
+        $parent_schema           = $this->get_thing_schema();
+        $schema['custom_fields'] = array_merge( $schema['custom_fields'], $parent_schema['custom_fields'] );
+        $schema['linked_data']   = array_merge( $schema['linked_data'], $parent_schema['linked_data'] );
+
+        return $schema;
+    }
+
+    /**
+     * Get the 'event' schema.
+     *
+     * @return array An array with the schema configuration.
+     *
+     * @since 3.1.0
+     */
+    private function get_event_schema() {
+
+        $schema = array(
+            'label'         => 'Event',
+            'description'   => 'An event . ',
+            'parents'       => array( 'thing' ),
+            'css_class'     => 'wl-event',
+            'uri'           => self::SCHEMA_EVENT_TYPE,
+            'same_as'       => array( 'http://dbpedia.org/ontology/Event' ),
+            'custom_fields' => array(
+                self::FIELD_DATE_START => array(
+                    'predicate'   => 'http://schema.org/startDate',
+                    'type'        => self::DATA_TYPE_DATE,
+                    'export_type' => 'xsd:dateTime',
+                    'constraints' => '',
+                ),
+                self::FIELD_DATE_END   => array(
+                    'predicate'   => 'http://schema.org/endDate',
+                    'type'        => self::DATA_TYPE_DATE,
+                    'export_type' => 'xsd:dateTime',
+                    'constraints' => '',
+                ),
+                self::FIELD_LOCATION   => array(
+                    'predicate'   => 'http://schema.org/location',
+                    'type'        => self::DATA_TYPE_URI,
+                    'export_type' => 'http://schema.org/PostalAddress',
+                    'constraints' => array(
+                        'uri_type'    => array( 'Place', 'LocalBusiness' ),
+                        'cardinality' => INF,
+                    ),
+                ),
+                self::FIELD_PERFORMER  => array(
+                    'predicate'   => 'http://schema.org/performer',
+                    'type'        => self::DATA_TYPE_URI,
+                    'export_type' => 'http://schema.org/Person',
+                    'constraints' => array(
+                        'uri_type'    => array( 'Person', 'Organization' ),
+                        'cardinality' => INF,
+                    ),
+                ),
+                self::FIELD_OFFERS     => array(
+                    'predicate'   => 'http://schema.org/offers',
+                    'type'        => self::DATA_TYPE_URI,
+                    'export_type' => 'http://schema.org/Offer',
+                    'constraints' => array(
+                        'uri_type'    => array( 'Offer' ),
+                        'cardinality' => INF,
+                    ),
+                ),
+            ),
+            'linked_data'   => array(
+                // ### schema:startDate.
+                $this->rendition_factory->create(
+                    $this->storage_factory->post_meta( self::FIELD_DATE_START ),
+                    'http://schema.org/startDate',
+                    self::DATA_TYPE_DATE_TIME
+                ),
+                // ### schema:endDate.
+                $this->rendition_factory->create(
+                    $this->storage_factory->post_meta( self::FIELD_DATE_END ),
+                    'http://schema.org/endDate',
+                    self::DATA_TYPE_DATE_TIME
+                ),
+                // ### schema:location.
+                $this->rendition_factory->create(
+                    $this->storage_factory->post_meta_to_uri( self::FIELD_LOCATION ),
+                    'http://schema.org/location',
+                    self::DATA_TYPE_URI
+                ),
+                // ### schema:performer.
+                $this->rendition_factory->create(
+                    $this->storage_factory->post_meta_to_uri( self::FIELD_PERFORMER ),
+                    'http://schema.org/performer',
+                    self::DATA_TYPE_URI
+                ),
+                // ### schema:offers.
+                $this->rendition_factory->create(
+                    $this->storage_factory->post_meta_to_uri( self::FIELD_OFFERS ),
+                    'http://schema.org/offers',
+                    self::DATA_TYPE_URI
+                ),
+            ),
+            'templates'     => array(
+                'subtitle' => '{{id}}',
+            ),
+        );
+
+        // Merge the custom fields with those provided by the thing schema.
+        $parent_schema           = $this->get_thing_schema();
+        $schema['custom_fields'] = array_merge( $schema['custom_fields'], $parent_schema['custom_fields'] );
+        $schema['linked_data']   = array_merge( $schema['linked_data'], $parent_schema['linked_data'] );
+
+        return $schema;
+    }
+
+    /**
+     * Get the 'organization' schema.
+     *
+     * @return array An array with the schema configuration.
+     *
+     * @since 3.1.0
+     */
+    private function get_organization_schema() {
+
+        $schema = array(
+            'label'         => 'Organization',
+            'description'   => 'An organization, including a government or a newspaper.',
+            'parents'       => array( 'thing' ),
+            'css_class'     => 'wl-organization',
+            'uri'           => 'http://schema.org/Organization',
+            'same_as'       => array(
+                'http://rdf.freebase.com/ns/organization.organization',
+                'http://rdf.freebase.com/ns/government.government',
+                'http://schema.org/Newspaper',
+            ),
+            'custom_fields' => array(
+                self::FIELD_LEGAL_NAME          => array(
+                    'predicate'   => 'http://schema.org/legalName',
+                    'type'        => self::DATA_TYPE_STRING,
+                    'export_type' => 'xsd:string',
+                    'constraints' => '',
+                ),
+                self::FIELD_FOUNDER             => array(
+                    'predicate'   => 'http://schema.org/founder',
+                    'type'        => self::DATA_TYPE_URI,
+                    'export_type' => 'http://schema.org/Person',
+                    'constraints' => array(
+                        'uri_type'    => 'Person',
+                        'cardinality' => INF,
+                    ),
+                ),
+                self::FIELD_ADDRESS             => array(
+                    'predicate'   => 'http://schema.org/streetAddress',
+                    'type'        => self::DATA_TYPE_STRING,
+                    'export_type' => 'xsd:string',
+                    'constraints' => '',
+                    // To build custom metabox.
+                    'input_field' => 'address',
+                ),
+                self::FIELD_ADDRESS_PO_BOX      => array(
+                    'predicate'   => 'http://schema.org/postOfficeBoxNumber',
+                    'type'        => self::DATA_TYPE_STRING,
+                    'export_type' => 'xsd:string',
+                    'constraints' => '',
+                    // To build custom metabox.
+                    'input_field' => 'address',
+                ),
+                self::FIELD_ADDRESS_POSTAL_CODE => array(
+                    'predicate'   => 'http://schema.org/postalCode',
+                    'type'        => self::DATA_TYPE_STRING,
+                    'export_type' => 'xsd:string',
+                    'constraints' => '',
+                    // To build custom metabox.
+                    'input_field' => 'address',
+                ),
+                self::FIELD_ADDRESS_LOCALITY    => array(
+                    'predicate'   => 'http://schema.org/addressLocality',
+                    'type'        => self::DATA_TYPE_STRING,
+                    'export_type' => 'xsd:string',
+                    'constraints' => '',
+                    // To build custom metabox.
+                    'input_field' => 'address',
+                ),
+                self::FIELD_ADDRESS_REGION      => array(
+                    'predicate'   => 'http://schema.org/addressRegion',
+                    'type'        => self::DATA_TYPE_STRING,
+                    'export_type' => 'xsd:string',
+                    'constraints' => '',
+                    // To build custom metabox.
+                    'input_field' => 'address',
+                ),
+                self::FIELD_ADDRESS_COUNTRY     => array(
+                    'predicate'   => 'http://schema.org/addressCountry',
+                    'type'        => self::DATA_TYPE_STRING,
+                    'export_type' => 'xsd:string',
+                    'constraints' => '',
+                    // To build custom metabox.
+                    'input_field' => 'address',
+                ),
+                self::FIELD_EMAIL               => array(
+                    'predicate'   => 'http://schema.org/email',
+                    'type'        => self::DATA_TYPE_STRING,
+                    'export_type' => 'xsd:string',
+                    'constraints' => '',
+                ),
+                self::FIELD_TELEPHONE           => array(
+                    'predicate'   => 'http://schema.org/telephone',
+                    'type'        => self::DATA_TYPE_STRING,
+                    'export_type' => 'xsd:string',
+                    'constraints' => '',
+                ),
+            ),
+            'linked_data'   => array(
+                // ### schema:legalName.
+                $this->rendition_factory->create(
+                    $this->storage_factory->post_meta( self::FIELD_LEGAL_NAME ),
+                    'http://schema.org/legalName'
+                ),
+                // ### schema:founder.
+                $this->rendition_factory->create(
+                    $this->storage_factory->post_meta_to_uri( self::FIELD_FOUNDER ),
+                    'http://schema.org/founder',
+                    self::DATA_TYPE_URI
+                ),
+                // ### schema:email.
+                $this->rendition_factory->create(
+                    $this->storage_factory->post_meta( self::FIELD_EMAIL ),
+                    'http://schema.org/email'
+                ),
+                // ### schema:telephone.
+                $this->rendition_factory->create(
+                    $this->storage_factory->post_meta( self::FIELD_TELEPHONE ),
+                    'http://schema.org/telephone'
+                ),
+            ),
+            'templates'     => array(
+                'subtitle' => '{{id}}',
+            ),
+        );
+
+        // Merge the custom fields with those provided by the thing schema.
+        $parent_schema           = $this->get_thing_schema();
+        $schema['custom_fields'] = array_merge( $schema['custom_fields'], $parent_schema['custom_fields'] );
+        $schema['linked_data']   = array_merge( $schema['linked_data'], $parent_schema['linked_data'] );
+
+        return $schema;
+    }
+
+    /**
+     * Get the 'person' schema.
+     *
+     * @return array An array with the schema configuration.
+     *
+     * @since 3.1.0
+     */
+    private function get_person_schema() {
+
+        $schema = array(
+            'label'         => 'Person',
+            'description'   => 'A person (or a music artist).',
+            'parents'       => array( 'thing' ),
+            'css_class'     => 'wl-person',
+            'uri'           => 'http://schema.org/Person',
+            'same_as'       => array(
+                'http://rdf.freebase.com/ns/people.person',
+                'http://rdf.freebase.com/ns/music.artist',
+                'http://dbpedia.org/class/yago/LivingPeople',
+            ),
+            'custom_fields' => array(
+                self::FIELD_KNOWS       => array(
+                    'predicate'   => 'http://schema.org/knows',
+                    'type'        => self::DATA_TYPE_URI,
+                    'export_type' => 'http://schema.org/Person',
+                    'constraints' => array(
+                        'uri_type'    => 'Person',
+                        'cardinality' => INF,
+                    ),
+                ),
+                self::FIELD_BIRTH_DATE  => array(
+                    'predicate'   => 'http://schema.org/birthDate',
+                    'type'        => self::DATA_TYPE_DATE,
+                    'export_type' => 'xsd:date',
+                    'constraints' => '',
+                ),
+                self::FIELD_BIRTH_PLACE => array(
+                    'predicate'   => 'http://schema.org/birthPlace',
+                    'type'        => self::DATA_TYPE_URI,
+                    'export_type' => 'http://schema.org/Place',
+                    'constraints' => array(
+                        'uri_type' => 'Place',
+                    ),
+                ),
+                self::FIELD_AFFILIATION => array(
+                    'predicate'   => 'http://schema.org/affiliation',
+                    'type'        => self::DATA_TYPE_URI,
+                    'export_type' => 'http://schema.org/Organization',
+                    'constraints' => array(
+                        'uri_type'    => array(
+                            'Organization',
+                            'LocalBusiness',
+                        ),
+                        'cardinality' => INF,
+                    ),
+                ),
+                self::FIELD_EMAIL       => array(
+                    'predicate'   => 'http://schema.org/email',
+                    'type'        => self::DATA_TYPE_STRING,
+                    'export_type' => 'xsd:string',
+                    'constraints' => array(
+                        'cardinality' => INF,
+                    ),
+                ),
+            ),
+            'linked_data'   => array(
+                // ### schema:knows.
+                $this->rendition_factory->create(
+                    $this->storage_factory->post_meta_to_uri( self::FIELD_KNOWS ),
+                    'http://schema.org/knows',
+                    self::DATA_TYPE_URI
+                ),
+                // ### schema:birthDate.
+                $this->rendition_factory->create(
+                    $this->storage_factory->post_meta( self::FIELD_BIRTH_DATE ),
+                    'http://schema.org/birthDate',
+                    self::DATA_TYPE_DATE
+                ),
+                // ### schema:birthPlace.
+                $this->rendition_factory->create(
+                    $this->storage_factory->post_meta_to_uri( self::FIELD_BIRTH_PLACE ),
+                    'http://schema.org/birthPlace',
+                    self::DATA_TYPE_URI
+                ),
+                // ### schema:affiliation.
+                $this->rendition_factory->create(
+                    $this->storage_factory->post_meta_to_uri( self::FIELD_AFFILIATION ),
+                    'http://schema.org/affiliation',
+                    self::DATA_TYPE_URI
+                ),
+                // ### schema:email.
+                $this->rendition_factory->create(
+                    $this->storage_factory->post_meta( self::FIELD_EMAIL ),
+                    'http://schema.org/email'
+                ),
+            ),
+            'templates'     => array(
+                'subtitle' => '{{id}}',
+            ),
+        );
+
+        // Merge the custom fields with those provided by the thing schema.
+        $parent_schema           = $this->get_thing_schema();
+        $schema['custom_fields'] = array_merge( $schema['custom_fields'], $parent_schema['custom_fields'] );
+        $schema['linked_data']   = array_merge( $schema['linked_data'], $parent_schema['linked_data'] );
+
+        return $schema;
+
+    }
+
+    /**
+     * Get the 'place' schema.
+     *
+     * @return array An array with the schema configuration.
+     *
+     * @since 3.1.0
+     */
+    private function get_place_schema() {
+
+        $schema = array(
+            'label'         => 'Place',
+            'description'   => 'A place.',
+            'parents'       => array( 'thing' ),
+            'css_class'     => 'wl-place',
+            'uri'           => 'http://schema.org/Place',
+            'same_as'       => array(
+                'http://rdf.freebase.com/ns/location.location',
+                'http://www.opengis.net/gml/_Feature',
+            ),
+            'custom_fields' => array(
+                self::FIELD_GEO_LATITUDE        => array(
+                    'predicate'   => 'http://schema.org/latitude',
+                    'type'        => self::DATA_TYPE_DOUBLE,
+                    'export_type' => 'xsd:double',
+                    'constraints' => '',
+                    // To build custom metabox.
+                    'input_field' => 'coordinates',
+                ),
+                self::FIELD_GEO_LONGITUDE       => array(
+                    'predicate'   => 'http://schema.org/longitude',
+                    'type'        => self::DATA_TYPE_DOUBLE,
+                    'export_type' => 'xsd:double',
+                    'constraints' => '',
+                    // To build custom metabox.
+                    'input_field' => 'coordinates',
+                ),
+                self::FIELD_ADDRESS             => array(
+                    'predicate'   => 'http://schema.org/streetAddress',
+                    'type'        => self::DATA_TYPE_STRING,
+                    'export_type' => 'xsd:string',
+                    'constraints' => '',
+                    // To build custom metabox.
+                    'input_field' => 'address',
+                ),
+                self::FIELD_ADDRESS_PO_BOX      => array(
+                    'predicate'   => 'http://schema.org/postOfficeBoxNumber',
+                    'type'        => self::DATA_TYPE_STRING,
+                    'export_type' => 'xsd:string',
+                    'constraints' => '',
+                    // To build custom metabox.
+                    'input_field' => 'address',
+                ),
+                self::FIELD_ADDRESS_POSTAL_CODE => array(
+                    'predicate'   => 'http://schema.org/postalCode',
+                    'type'        => self::DATA_TYPE_STRING,
+                    'export_type' => 'xsd:string',
+                    'constraints' => '',
+                    // To build custom metabox.
+                    'input_field' => 'address',
+                ),
+                self::FIELD_ADDRESS_LOCALITY    => array(
+                    'predicate'   => 'http://schema.org/addressLocality',
+                    'type'        => self::DATA_TYPE_STRING,
+                    'export_type' => 'xsd:string',
+                    'constraints' => '',
+                    // To build custom metabox.
+                    'input_field' => 'address',
+                ),
+                self::FIELD_ADDRESS_REGION      => array(
+                    'predicate'   => 'http://schema.org/addressRegion',
+                    'type'        => self::DATA_TYPE_STRING,
+                    'export_type' => 'xsd:string',
+                    'constraints' => '',
+                    // To build custom metabox.
+                    'input_field' => 'address',
+                ),
+                self::FIELD_ADDRESS_COUNTRY     => array(
+                    'predicate'   => 'http://schema.org/addressCountry',
+                    'type'        => self::DATA_TYPE_STRING,
+                    'export_type' => 'xsd:string',
+                    'constraints' => '',
+                    // To build custom metabox.
+                    'input_field' => 'address',
+                ),
+            ),
+            'linked_data'   => array(
+                $this->rendition_factory->create_address(
+                    $this->storage_factory,
+                    $this->language_code
+                ),
+            ),
+            'templates'     => array(
+                'subtitle' => '{{id}}',
+            ),
+        );
+
+        // Merge the custom fields with those provided by the thing schema.
+        $parent_schema           = $this->get_thing_schema();
+        $schema['custom_fields'] = array_merge( $schema['custom_fields'], $parent_schema['custom_fields'] );
+        $schema['linked_data']   = array_merge( $schema['linked_data'], $parent_schema['linked_data'] );
+
+        return $schema;
+    }
+
+    /**
+     * Get the 'local business' schema.
+     *
+     * @return array An array with the schema configuration.
+     *
+     * @since 3.1.0
+     */
+    private function get_local_business_schema() {
+
+        $schema = array(
+            'label'         => 'LocalBusiness',
+            'description'   => 'A local business.',
+            'parents'       => array( 'place', 'organization' ),
+            'css_class'     => 'wl-local-business',
+            'uri'           => 'http://schema.org/LocalBusiness',
+            'same_as'       => array(
+                'http://rdf.freebase.com/ns/business/business_location',
+                'https://schema.org/Store',
+            ),
+            'custom_fields' => array(),
+            'linked_data'   => array(),
+            'templates'     => array(
+                'subtitle' => '{{id}}',
+            ),
+        );
+
+        // Merge the custom fields with those provided by the place and organization schema.
+        $place_schema            = $this->get_place_schema();
+        $organization_schema     = $this->get_organization_schema();
+        $schema['custom_fields'] = array_merge( $schema['custom_fields'], $place_schema['custom_fields'], $organization_schema['custom_fields'] );
+        $schema['linked_data']   = array_merge( $schema['linked_data'], $place_schema['linked_data'], $organization_schema['linked_data'] );
+
+        return $schema;
+    }
+
+    /**
+     * Get the 'recipe' schema.
+     *
+     * @return array An array with the schema configuration.
+     *
+     * @since 3.14.0
+     */
+    private function get_recipe_schema() {
+
+        $schema = array(
+            'label'         => 'Recipe',
+            'description'   => 'A Recipe.',
+            'parents'       => array( 'CreativeWork' ),
+            'css_class'     => 'wl-recipe',
+            'uri'           => 'http://schema.org/Recipe',
+            'same_as'       => array(),
+            'templates'     => array(
+                'subtitle' => '{{id}}',
+            ),
+            'custom_fields' => array(
+                self::FIELD_RECIPE_CUISINE          => array(
+                    'predicate'   => 'http://schema.org/recipeCuisine',
+                    'type'        => self::DATA_TYPE_STRING,
+                    'export_type' => 'xsd:string',
+                    'constraints' => '',
+                    'metabox'     => array(
+                        'label' => __( 'Recipe cuisine', 'wordlift' ),
+                    ),
+                ),
+                self::FIELD_RECIPE_INGREDIENT       => array(
+                    'predicate'   => 'http://schema.org/recipeIngredient',
+                    'type'        => self::DATA_TYPE_STRING,
+                    'export_type' => 'xsd:string',
+                    'constraints' => array(
+                        'cardinality' => INF,
+                    ),
+                    'metabox'     => array(
+                        'label' => __( 'Recipe ingredient', 'wordlift' ),
+                    ),
+                ),
+                self::FIELD_RECIPE_INSTRUCTIONS     => array(
+                    'predicate'   => 'http://schema.org/recipeInstructions',
+                    'type'        => self::DATA_TYPE_MULTILINE,
+                    'export_type' => 'xsd:string',
+                    'constraints' => '',
+                    'metabox'     => array(
+                        'class' => 'Wordlift_Metabox_Field_Multiline',
+                        'label' => __( 'Recipe instructions', 'wordlift' ),
+                    ),
+                ),
+                self::FIELD_RECIPE_YIELD            => array(
+                    'predicate'   => 'http://schema.org/recipeYield',
+                    'type'        => self::DATA_TYPE_STRING,
+                    'export_type' => 'xsd:string',
+                    'constraints' => '',
+                    'metabox'     => array(
+                        'label' => __( 'Recipe number of servings', 'wordlift' ),
+                    ),
+                ),
+                self::FIELD_RECIPE_INGREDIENT       => array(
+                    'predicate'   => 'http://schema.org/recipeIngredient',
+                    'type'        => self::DATA_TYPE_STRING,
+                    'export_type' => 'xsd:string',
+                    'constraints' => array(
+                        'cardinality' => INF,
+                    ),
+                    'metabox'     => array(
+                        'label' => __( 'Recipe ingredient', 'wordlift' ),
+                    ),
+                ),
+                self::FIELD_NUTRITION_INFO_CALORIES => array(
+                    'predicate'   => 'http://schema.org/calories',
+                    'type'        => self::DATA_TYPE_STRING,
+                    'export_type' => 'xsd:string',
+                    'constraints' => '',
+                    'metabox'     => array(
+                        'label' => __( 'Calories (e.g. 240 calories)', 'wordlift' ),
+                    ),
+                ),
+                self::FIELD_PREP_TIME               => array(
+                    'predicate'   => 'http://schema.org/prepTime',
+                    'type'        => self::DATA_TYPE_DURATION,
+                    'export_type' => 'xsd:time',
+                    'constraints' => '',
+                    'metabox'     => array(
+                        'class' => 'Wordlift_Metabox_Field_Duration',
+                        'label' => __( 'Recipe preparation time (e.g. 1:30)', 'wordlift' ),
+                    ),
+                ),
+                self::FIELD_COOK_TIME               => array(
+                    'predicate'   => 'http://schema.org/cookTime',
+                    'type'        => self::DATA_TYPE_DURATION,
+                    'export_type' => 'xsd:time',
+                    'constraints' => '',
+                    'metabox'     => array(
+                        'class' => 'Wordlift_Metabox_Field_Duration',
+                        'label' => __( 'Recipe cook time (e.g. 1:30)', 'wordlift' ),
+                    ),
+                ),
+                self::FIELD_TOTAL_TIME              => array(
+                    'predicate'   => 'http://schema.org/totalTime',
+                    'type'        => self::DATA_TYPE_DURATION,
+                    'export_type' => 'xsd:time',
+                    'constraints' => '',
+                    'metabox'     => array(
+                        'class' => 'Wordlift_Metabox_Field_Duration',
+                        'label' => __( 'Recipe total time (e.g. 1:30)', 'wordlift' ),
+                    ),
+                ),
+            ),
+            'linked_data'   => array(
+                // ### schema:recipeCuisine.
+                $this->rendition_factory->create(
+                    $this->storage_factory->post_meta( self::FIELD_RECIPE_CUISINE ),
+                    'http://schema.org/recipeCuisine'
+                ),
+                // ### schema:recipeIngredient.
+                $this->rendition_factory->create(
+                    $this->storage_factory->post_meta( self::FIELD_RECIPE_INGREDIENT ),
+                    'http://schema.org/recipeIngredient'
+                ),
+                // ### schema:recipeInstructions.
+                $this->rendition_factory->create(
+                    $this->storage_factory->post_meta( self::FIELD_RECIPE_INSTRUCTIONS ),
+                    'http://schema.org/recipeInstructions'
+                ),
+                // ### schema:recipeYield.
+                $this->rendition_factory->create(
+                    $this->storage_factory->post_meta( self::FIELD_RECIPE_YIELD ),
+                    'http://schema.org/recipeYield'
+                ),
+                // ### schema:prepTime.
+                $this->rendition_factory->create(
+                    $this->storage_factory->post_meta( self::FIELD_PREP_TIME ),
+                    'http://schema.org/prepTime',
+                    self::DATA_TYPE_DURATION
+                ),
+                // ### schema:cookTime.
+                $this->rendition_factory->create(
+                    $this->storage_factory->post_meta( self::FIELD_COOK_TIME ),
+                    'http://schema.org/cookTime',
+                    self::DATA_TYPE_DURATION
+                ),
+                // ### schema:totalTime.
+                $this->rendition_factory->create(
+                    $this->storage_factory->post_meta( self::FIELD_TOTAL_TIME ),
+                    'http://schema.org/totalTime',
+                    self::DATA_TYPE_DURATION
+                ),
+            ),
+        );
+
+        // Merge the custom fields with those provided by the parent schema.
+        $parent_schema           = $this->get_creative_work_schema();
+        $schema['custom_fields'] = array_merge( $schema['custom_fields'], $parent_schema['custom_fields'] );
+        $schema['linked_data']   = array_merge( $schema['linked_data'], $parent_schema['linked_data'] );
+
+        return $schema;
+    }
+
+    /**
+     * Get the 'offer' schema.
+     *
+     * @return array An array with the schema configuration.
+     *
+     * @since 3.18.0
+     */
+    private function get_offer_schema() {
+
+        $schema = array(
+            'label'         => 'Offer',
+            'description'   => 'An offer. ',
+            'parents'       => array( 'thing' ),
+            'css_class'     => 'wl-offer',
+            'uri'           => self::SCHEMA_OFFER_TYPE,
+            'same_as'       => array(),
+            'templates'     => array(
+                'subtitle' => '{{id}}',
+            ),
+            'custom_fields' => array(
+                self::FIELD_AVAILABILITY        => array(
+                    'predicate'   => 'http://schema.org/availability',
+                    'type'        => self::DATA_TYPE_STRING,
+                    'export_type' => 'xsd:string',
+                    'metabox'     => array(
+                        'class' => 'Wordlift_Metabox_Field_Select',
+                    ),
+                    'options'     => array(
+                        'Discontinued'        => esc_html__( 'Discontinued', 'wordlift' ),
+                        'InStock'             => esc_html__( 'In Stock', 'wordlift' ),
+                        'InStoreOnly'         => esc_html__( 'In Store Only', 'wordlift' ),
+                        'LimitedAvailability' => esc_html__( 'Limited Availability', 'wordlift' ),
+                        'OnlineOnly'          => esc_html__( 'Online Only', 'wordlift' ),
+                        'OutOfStock'          => esc_html__( 'Out of Stock', 'wordlift' ),
+                        'PreOrder'            => esc_html__( 'Pre Order', 'wordlift' ),
+                        'PreSale'             => esc_html__( 'Pre Sale', 'wordlift' ),
+                        'SoldOut'             => esc_html__( 'Sold Out', 'wordlift' ),
+                    ),
+                ),
+                self::FIELD_PRICE               => array(
+                    'predicate'   => 'http://schema.org/price',
+                    'type'        => self::DATA_TYPE_STRING,
+                    'export_type' => 'xsd:integer',
+                    'metabox'     => array(
+                        'class' => 'Wordlift_Metabox_Field_Integer',
+                    ),
+                ),
+                self::FIELD_PRICE_CURRENCY      => array(
+                    'predicate'   => 'http://schema.org/priceCurrency',
+                    'type'        => self::DATA_TYPE_STRING,
+                    'export_type' => 'xsd:string',
+                ),
+                self::FIELD_AVAILABILITY_STARTS => array(
+                    'predicate'   => 'http://schema.org/availabilityStarts',
+                    'type'        => self::DATA_TYPE_DATE,
+                    'export_type' => 'xsd:dateTime',
+                ),
+                self::FIELD_AVAILABILITY_ENDS   => array(
+                    'predicate'   => 'http://schema.org/availabilityEnds',
+                    'type'        => self::DATA_TYPE_DATE,
+                    'export_type' => 'xsd:dateTime',
+                ),
+                self::FIELD_INVENTORY_LEVEL     => array(
+                    'predicate'   => 'http://schema.org/inventoryLevel',
+                    'type'        => self::DATA_TYPE_STRING,
+                    'export_type' => 'xsd:integer',
+                    'metabox'     => array(
+                        'class' => 'Wordlift_Metabox_Field_Integer',
+                    ),
+                ),
+                self::FIELD_VALID_FROM          => array(
+                    'predicate'   => 'http://schema.org/validFrom',
+                    'type'        => self::DATA_TYPE_DATE,
+                    'export_type' => 'xsd:dateTime',
+                ),
+                self::FIELD_PRICE_VALID_UNTIL   => array(
+                    'predicate'   => 'http://schema.org/priceValidUntil',
+                    'type'        => self::DATA_TYPE_DATE,
+                    'export_type' => 'xsd:dateTime',
+                ),
+                self::FIELD_ITEM_OFFERED        => array(
+                    'predicate'   => 'http://schema.org/itemOffered',
+                    'type'        => self::DATA_TYPE_URI,
+                    'export_type' => 'http://schema.org/Thing',
+                    'constraints' => array(
+                        'uri_type'    => array(
+                            'Event',
+                            'Thing',
+                        ),
+                        'cardinality' => INF,
+                    ),
+                ),
+            ),
+            'linked_data'   => array(
+                // ### schema:availability.
+                $this->rendition_factory->create(
+                    $this->storage_factory->post_meta( self::FIELD_AVAILABILITY ),
+                    'http://schema.org/availability',
+                    null
+                ),
+                // ### schema:availabilityStarts.
+                $this->rendition_factory->create(
+                    $this->storage_factory->post_meta( self::FIELD_AVAILABILITY_STARTS ),
+                    'http://schema.org/availabilityStarts',
+                    self::DATA_TYPE_DATE_TIME
+                ),
+                // ### schema:availabilityEnds.
+                $this->rendition_factory->create(
+                    $this->storage_factory->post_meta( self::FIELD_AVAILABILITY_ENDS ),
+                    'http://schema.org/availabilityEnds',
+                    self::DATA_TYPE_DATE_TIME
+                ),
+                // ### schema:inventoryLevel.
+                $this->rendition_factory->create(
+                    $this->storage_factory->post_meta( self::FIELD_INVENTORY_LEVEL ),
+                    'http://schema.org/inventoryLevel',
+                    self::DATA_TYPE_INTEGER
+                ),
+                // ### schema:price.
+                $this->rendition_factory->create(
+                    $this->storage_factory->post_meta( self::FIELD_PRICE ),
+                    'http://schema.org/price',
+                    self::DATA_TYPE_INTEGER
+                ),
+                // ### schema:priceCurrency.
+                $this->rendition_factory->create(
+                    $this->storage_factory->post_meta( self::FIELD_PRICE_CURRENCY ),
+                    'http://schema.org/priceCurrency',
+                    null
+                ),
+                // ### schema:validFrom.
+                $this->rendition_factory->create(
+                    $this->storage_factory->post_meta( self::FIELD_VALID_FROM ),
+                    'http://schema.org/validFrom',
+                    null
+                ),
+                // ### schema:priceValidUntil.
+                $this->rendition_factory->create(
+                    $this->storage_factory->post_meta( self::FIELD_PRICE_VALID_UNTIL ),
+                    'http://schema.org/priceValidUntil',
+                    null
+                ),
+                // ### schema:itemOffered.
+                $this->rendition_factory->create(
+                    $this->storage_factory->post_meta_to_uri( self::FIELD_ITEM_OFFERED ),
+                    'http://schema.org/itemOffered',
+                    self::DATA_TYPE_URI
+                ),
+            ),
+        );
+
+        // Merge the custom fields with those provided by the thing schema.
+        $parent_schema           = $this->get_thing_schema();
+        $schema['custom_fields'] = array_merge( $schema['custom_fields'], $parent_schema['custom_fields'] );
+        $schema['linked_data']   = array_merge( $schema['linked_data'], $parent_schema['linked_data'] );
+
+        return $schema;
+    }
+
+    /**
+     * Get the 'article' schema.
+     *
+     * @return array An array with the schema configuration.
+     *
+     * @since 3.15.0
+     */
+    private function get_article_schema() {
+
+        $schema = array(
+            'label'         => 'Article',
+            'description'   => 'An Article.',
+            'parents'       => array(),
+            'css_class'     => 'wl-article',
+            'uri'           => 'http://schema.org/Article',
+            'same_as'       => array(),
+            'templates'     => array(
+                'subtitle' => '{{id}}',
+            ),
+            'custom_fields' => array(),
+            'linked_data'   => array(
+                // ### schema:headline.
+                $this->rendition_factory->create(
+                    $this->storage_factory->post_title(),
+                    'http://schema.org/headline',
+                    null,
+                    $this->language_code
+                ),
+                // ### schema:url.
+                $this->rendition_factory->create(
+                    $this->storage_factory->url_property(),
+                    Wordlift_Query_Builder::SCHEMA_URL_URI,
+                    self::DATA_TYPE_URI
+                ),
+                // ### rdf:type.
+                $this->rendition_factory->create(
+                    $this->storage_factory->schema_class(),
+                    Wordlift_Query_Builder::RDFS_TYPE_URI,
+                    self::DATA_TYPE_URI
+                ),
+                // ### dcterms:references.
+                $this->rendition_factory->create(
+                    $this->storage_factory->relations(),
+                    Wordlift_Query_Builder::DCTERMS_REFERENCES_URI,
+                    self::DATA_TYPE_URI,
+                    $this->language_code
+                ),
+            ),
+        );
+
+        return $schema;
+    }
 
 }

Spacing +97 added lines, -97 removed lines

@@ -467,9 +467,9 @@ 
 	 * @param \Wordlift_Sparql_Tuple_Rendition_Factory $rendition_factory     The {@link Wordlift_Sparql_Tuple_Rendition_Factory} instance.
 	 * @param \Wordlift_Configuration_Service          $configuration_service The {@link Wordlift_Configuration_Service} instance.
 	 */
-	public function __construct( $storage_factory, $rendition_factory, $configuration_service ) {
+	public function __construct($storage_factory, $rendition_factory, $configuration_service) {
 
-		$this->log = Wordlift_Log_Service::get_logger( 'Wordlift_Schema_Service' );
+		$this->log = Wordlift_Log_Service::get_logger('Wordlift_Schema_Service');
 
 		$this->storage_factory       = $storage_factory;
 		$this->rendition_factory     = $rendition_factory;
@@ -519,18 +519,18 @@ 
 	 *
 	 * @return null|array An array of field's properties or null if the field is not found.
 	 */
-	public function get_field( $key ) {
+	public function get_field($key) {
 
 		// Parse each schema's fields until we find the one we're looking for, then
 		// return its properties.
-		foreach ( $this->schema as $_ => $schema ) {
+		foreach ($this->schema as $_ => $schema) {
 
-			if ( ! isset( $schema['custom_fields'] ) ) {
+			if ( ! isset($schema['custom_fields'])) {
 				break;
 			}
 
-			foreach ( $schema['custom_fields'] as $field => $props ) {
-				if ( $key === $field ) {
+			foreach ($schema['custom_fields'] as $field => $props) {
+				if ($key === $field) {
 					return $props;
 				}
 			}
@@ -550,8 +550,8 @@ 
 		// Get the custom fields.
 		$renditions = array_reduce(
 			$this->schema,
-			function ( $carry, $item ) {
-				return array_merge( $carry, $item['linked_data'] );
+			function($carry, $item) {
+				return array_merge($carry, $item['linked_data']);
 			},
 			array()
 		);
@@ -569,14 +569,14 @@ 
 	 *
 	 * @since 3.1.0
 	 */
-	public function get_schema( $name ) {
+	public function get_schema($name) {
 		// Check if the schema exists and, if not, return NULL.
-		if ( ! isset( $this->schema[ $name ] ) ) {
+		if ( ! isset($this->schema[$name])) {
 			return null;
 		}
 
 		// Return the requested schema.
-		return $this->schema[ $name ];
+		return $this->schema[$name];
 	}
 
 	/**
@@ -588,10 +588,10 @@ 
 	 *
 	 * @since 3.3.0
 	 */
-	public function get_schema_by_uri( $uri ) {
+	public function get_schema_by_uri($uri) {
 
-		foreach ( $this->schema as $name => $schema ) {
-			if ( $schema['uri'] === $uri ) {
+		foreach ($this->schema as $name => $schema) {
+			if ($schema['uri'] === $uri) {
 				return $schema;
 			}
 		}
@@ -611,7 +611,7 @@ 
 		return array(
 			'css_class'     => 'wl-thing',
 			'uri'           => 'http://schema.org/Thing',
-			'same_as'       => array( '*' ),
+			'same_as'       => array('*'),
 			// set as default.
 			'custom_fields' => array(
 				self::FIELD_SAME_AS                            => array(
@@ -650,14 +650,14 @@ 
 				),
 				// ### Alternative title to rdfs:label.
 				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( Wordlift_Entity_Service::ALTERNATIVE_LABEL_META_KEY ),
+					$this->storage_factory->post_meta(Wordlift_Entity_Service::ALTERNATIVE_LABEL_META_KEY),
 					Wordlift_Query_Builder::RDFS_LABEL_URI,
 					null,
 					$this->language_code
 				),
 				// ### Alternative title to dct:title.
 				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( Wordlift_Entity_Service::ALTERNATIVE_LABEL_META_KEY ),
+					$this->storage_factory->post_meta(Wordlift_Entity_Service::ALTERNATIVE_LABEL_META_KEY),
 					'http://purl.org/dc/terms/title',
 					null,
 					$this->language_code
@@ -671,7 +671,7 @@ 
 				),
 				// ### Alternative title to schema:alterName.
 				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( Wordlift_Entity_Service::ALTERNATIVE_LABEL_META_KEY ),
+					$this->storage_factory->post_meta(Wordlift_Entity_Service::ALTERNATIVE_LABEL_META_KEY),
 					'http://schema.org/alternateName',
 					null,
 					$this->language_code
@@ -691,7 +691,7 @@ 
 				),
 				// ### owl:sameAs.
 				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( self::FIELD_SAME_AS ),
+					$this->storage_factory->post_meta(self::FIELD_SAME_AS),
 					'http://www.w3.org/2002/07/owl#sameAs',
 					self::DATA_TYPE_URI
 				),
@@ -774,7 +774,7 @@ 
 		$schema = array(
 			'label'         => 'CreativeWork',
 			'description'   => 'A creative work (or a Music Album).',
-			'parents'       => array( 'thing' ),
+			'parents'       => array('thing'),
 			// Give term slug as parent.
 			'css_class'     => 'wl-creative-work',
 			'uri'           => 'http://schema.org/CreativeWork',
@@ -788,7 +788,7 @@ 
 					'type'        => self::DATA_TYPE_URI,
 					'export_type' => 'http://schema.org/Person',
 					'constraints' => array(
-						'uri_type'    => array( 'Person', 'Organization' ),
+						'uri_type'    => array('Person', 'Organization'),
 						'cardinality' => INF,
 					),
 				),
@@ -808,8 +808,8 @@ 
 
 		// Merge the custom fields with those provided by the thing schema.
 		$parent_schema           = $this->get_thing_schema();
-		$schema['custom_fields'] = array_merge( $schema['custom_fields'], $parent_schema['custom_fields'] );
-		$schema['linked_data']   = array_merge( $schema['linked_data'], $parent_schema['linked_data'] );
+		$schema['custom_fields'] = array_merge($schema['custom_fields'], $parent_schema['custom_fields']);
+		$schema['linked_data']   = array_merge($schema['linked_data'], $parent_schema['linked_data']);
 
 		return $schema;
 	}
@@ -826,10 +826,10 @@ 
 		$schema = array(
 			'label'         => 'Event',
 			'description'   => 'An event . ',
-			'parents'       => array( 'thing' ),
+			'parents'       => array('thing'),
 			'css_class'     => 'wl-event',
 			'uri'           => self::SCHEMA_EVENT_TYPE,
-			'same_as'       => array( 'http://dbpedia.org/ontology/Event' ),
+			'same_as'       => array('http://dbpedia.org/ontology/Event'),
 			'custom_fields' => array(
 				self::FIELD_DATE_START => array(
 					'predicate'   => 'http://schema.org/startDate',
@@ -848,7 +848,7 @@ 
 					'type'        => self::DATA_TYPE_URI,
 					'export_type' => 'http://schema.org/PostalAddress',
 					'constraints' => array(
-						'uri_type'    => array( 'Place', 'LocalBusiness' ),
+						'uri_type'    => array('Place', 'LocalBusiness'),
 						'cardinality' => INF,
 					),
 				),
@@ -857,7 +857,7 @@ 
 					'type'        => self::DATA_TYPE_URI,
 					'export_type' => 'http://schema.org/Person',
 					'constraints' => array(
-						'uri_type'    => array( 'Person', 'Organization' ),
+						'uri_type'    => array('Person', 'Organization'),
 						'cardinality' => INF,
 					),
 				),
@@ -866,7 +866,7 @@ 
 					'type'        => self::DATA_TYPE_URI,
 					'export_type' => 'http://schema.org/Offer',
 					'constraints' => array(
-						'uri_type'    => array( 'Offer' ),
+						'uri_type'    => array('Offer'),
 						'cardinality' => INF,
 					),
 				),
@@ -874,31 +874,31 @@ 
 			'linked_data'   => array(
 				// ### schema:startDate.
 				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( self::FIELD_DATE_START ),
+					$this->storage_factory->post_meta(self::FIELD_DATE_START),
 					'http://schema.org/startDate',
 					self::DATA_TYPE_DATE_TIME
 				),
 				// ### schema:endDate.
 				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( self::FIELD_DATE_END ),
+					$this->storage_factory->post_meta(self::FIELD_DATE_END),
 					'http://schema.org/endDate',
 					self::DATA_TYPE_DATE_TIME
 				),
 				// ### schema:location.
 				$this->rendition_factory->create(
-					$this->storage_factory->post_meta_to_uri( self::FIELD_LOCATION ),
+					$this->storage_factory->post_meta_to_uri(self::FIELD_LOCATION),
 					'http://schema.org/location',
 					self::DATA_TYPE_URI
 				),
 				// ### schema:performer.
 				$this->rendition_factory->create(
-					$this->storage_factory->post_meta_to_uri( self::FIELD_PERFORMER ),
+					$this->storage_factory->post_meta_to_uri(self::FIELD_PERFORMER),
 					'http://schema.org/performer',
 					self::DATA_TYPE_URI
 				),
 				// ### schema:offers.
 				$this->rendition_factory->create(
-					$this->storage_factory->post_meta_to_uri( self::FIELD_OFFERS ),
+					$this->storage_factory->post_meta_to_uri(self::FIELD_OFFERS),
 					'http://schema.org/offers',
 					self::DATA_TYPE_URI
 				),
@@ -910,8 +910,8 @@ 
 
 		// Merge the custom fields with those provided by the thing schema.
 		$parent_schema           = $this->get_thing_schema();
-		$schema['custom_fields'] = array_merge( $schema['custom_fields'], $parent_schema['custom_fields'] );
-		$schema['linked_data']   = array_merge( $schema['linked_data'], $parent_schema['linked_data'] );
+		$schema['custom_fields'] = array_merge($schema['custom_fields'], $parent_schema['custom_fields']);
+		$schema['linked_data']   = array_merge($schema['linked_data'], $parent_schema['linked_data']);
 
 		return $schema;
 	}
@@ -928,7 +928,7 @@ 
 		$schema = array(
 			'label'         => 'Organization',
 			'description'   => 'An organization, including a government or a newspaper.',
-			'parents'       => array( 'thing' ),
+			'parents'       => array('thing'),
 			'css_class'     => 'wl-organization',
 			'uri'           => 'http://schema.org/Organization',
 			'same_as'       => array(
@@ -1016,23 +1016,23 @@ 
 			'linked_data'   => array(
 				// ### schema:legalName.
 				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( self::FIELD_LEGAL_NAME ),
+					$this->storage_factory->post_meta(self::FIELD_LEGAL_NAME),
 					'http://schema.org/legalName'
 				),
 				// ### schema:founder.
 				$this->rendition_factory->create(
-					$this->storage_factory->post_meta_to_uri( self::FIELD_FOUNDER ),
+					$this->storage_factory->post_meta_to_uri(self::FIELD_FOUNDER),
 					'http://schema.org/founder',
 					self::DATA_TYPE_URI
 				),
 				// ### schema:email.
 				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( self::FIELD_EMAIL ),
+					$this->storage_factory->post_meta(self::FIELD_EMAIL),
 					'http://schema.org/email'
 				),
 				// ### schema:telephone.
 				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( self::FIELD_TELEPHONE ),
+					$this->storage_factory->post_meta(self::FIELD_TELEPHONE),
 					'http://schema.org/telephone'
 				),
 			),
@@ -1043,8 +1043,8 @@ 
 
 		// Merge the custom fields with those provided by the thing schema.
 		$parent_schema           = $this->get_thing_schema();
-		$schema['custom_fields'] = array_merge( $schema['custom_fields'], $parent_schema['custom_fields'] );
-		$schema['linked_data']   = array_merge( $schema['linked_data'], $parent_schema['linked_data'] );
+		$schema['custom_fields'] = array_merge($schema['custom_fields'], $parent_schema['custom_fields']);
+		$schema['linked_data']   = array_merge($schema['linked_data'], $parent_schema['linked_data']);
 
 		return $schema;
 	}
@@ -1061,7 +1061,7 @@ 
 		$schema = array(
 			'label'         => 'Person',
 			'description'   => 'A person (or a music artist).',
-			'parents'       => array( 'thing' ),
+			'parents'       => array('thing'),
 			'css_class'     => 'wl-person',
 			'uri'           => 'http://schema.org/Person',
 			'same_as'       => array(
@@ -1117,31 +1117,31 @@ 
 			'linked_data'   => array(
 				// ### schema:knows.
 				$this->rendition_factory->create(
-					$this->storage_factory->post_meta_to_uri( self::FIELD_KNOWS ),
+					$this->storage_factory->post_meta_to_uri(self::FIELD_KNOWS),
 					'http://schema.org/knows',
 					self::DATA_TYPE_URI
 				),
 				// ### schema:birthDate.
 				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( self::FIELD_BIRTH_DATE ),
+					$this->storage_factory->post_meta(self::FIELD_BIRTH_DATE),
 					'http://schema.org/birthDate',
 					self::DATA_TYPE_DATE
 				),
 				// ### schema:birthPlace.
 				$this->rendition_factory->create(
-					$this->storage_factory->post_meta_to_uri( self::FIELD_BIRTH_PLACE ),
+					$this->storage_factory->post_meta_to_uri(self::FIELD_BIRTH_PLACE),
 					'http://schema.org/birthPlace',
 					self::DATA_TYPE_URI
 				),
 				// ### schema:affiliation.
 				$this->rendition_factory->create(
-					$this->storage_factory->post_meta_to_uri( self::FIELD_AFFILIATION ),
+					$this->storage_factory->post_meta_to_uri(self::FIELD_AFFILIATION),
 					'http://schema.org/affiliation',
 					self::DATA_TYPE_URI
 				),
 				// ### schema:email.
 				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( self::FIELD_EMAIL ),
+					$this->storage_factory->post_meta(self::FIELD_EMAIL),
 					'http://schema.org/email'
 				),
 			),
@@ -1152,8 +1152,8 @@ 
 
 		// Merge the custom fields with those provided by the thing schema.
 		$parent_schema           = $this->get_thing_schema();
-		$schema['custom_fields'] = array_merge( $schema['custom_fields'], $parent_schema['custom_fields'] );
-		$schema['linked_data']   = array_merge( $schema['linked_data'], $parent_schema['linked_data'] );
+		$schema['custom_fields'] = array_merge($schema['custom_fields'], $parent_schema['custom_fields']);
+		$schema['linked_data']   = array_merge($schema['linked_data'], $parent_schema['linked_data']);
 
 		return $schema;
 
@@ -1171,7 +1171,7 @@ 
 		$schema = array(
 			'label'         => 'Place',
 			'description'   => 'A place.',
-			'parents'       => array( 'thing' ),
+			'parents'       => array('thing'),
 			'css_class'     => 'wl-place',
 			'uri'           => 'http://schema.org/Place',
 			'same_as'       => array(
@@ -1257,8 +1257,8 @@ 
 
 		// Merge the custom fields with those provided by the thing schema.
 		$parent_schema           = $this->get_thing_schema();
-		$schema['custom_fields'] = array_merge( $schema['custom_fields'], $parent_schema['custom_fields'] );
-		$schema['linked_data']   = array_merge( $schema['linked_data'], $parent_schema['linked_data'] );
+		$schema['custom_fields'] = array_merge($schema['custom_fields'], $parent_schema['custom_fields']);
+		$schema['linked_data']   = array_merge($schema['linked_data'], $parent_schema['linked_data']);
 
 		return $schema;
 	}
@@ -1275,7 +1275,7 @@ 
 		$schema = array(
 			'label'         => 'LocalBusiness',
 			'description'   => 'A local business.',
-			'parents'       => array( 'place', 'organization' ),
+			'parents'       => array('place', 'organization'),
 			'css_class'     => 'wl-local-business',
 			'uri'           => 'http://schema.org/LocalBusiness',
 			'same_as'       => array(
@@ -1292,8 +1292,8 @@ 
 		// Merge the custom fields with those provided by the place and organization schema.
 		$place_schema            = $this->get_place_schema();
 		$organization_schema     = $this->get_organization_schema();
-		$schema['custom_fields'] = array_merge( $schema['custom_fields'], $place_schema['custom_fields'], $organization_schema['custom_fields'] );
-		$schema['linked_data']   = array_merge( $schema['linked_data'], $place_schema['linked_data'], $organization_schema['linked_data'] );
+		$schema['custom_fields'] = array_merge($schema['custom_fields'], $place_schema['custom_fields'], $organization_schema['custom_fields']);
+		$schema['linked_data']   = array_merge($schema['linked_data'], $place_schema['linked_data'], $organization_schema['linked_data']);
 
 		return $schema;
 	}
@@ -1310,7 +1310,7 @@ 
 		$schema = array(
 			'label'         => 'Recipe',
 			'description'   => 'A Recipe.',
-			'parents'       => array( 'CreativeWork' ),
+			'parents'       => array('CreativeWork'),
 			'css_class'     => 'wl-recipe',
 			'uri'           => 'http://schema.org/Recipe',
 			'same_as'       => array(),
@@ -1324,7 +1324,7 @@ 
 					'export_type' => 'xsd:string',
 					'constraints' => '',
 					'metabox'     => array(
-						'label' => __( 'Recipe cuisine', 'wordlift' ),
+						'label' => __('Recipe cuisine', 'wordlift'),
 					),
 				),
 				self::FIELD_RECIPE_INGREDIENT       => array(
@@ -1335,7 +1335,7 @@ 
 						'cardinality' => INF,
 					),
 					'metabox'     => array(
-						'label' => __( 'Recipe ingredient', 'wordlift' ),
+						'label' => __('Recipe ingredient', 'wordlift'),
 					),
 				),
 				self::FIELD_RECIPE_INSTRUCTIONS     => array(
@@ -1345,7 +1345,7 @@ 
 					'constraints' => '',
 					'metabox'     => array(
 						'class' => 'Wordlift_Metabox_Field_Multiline',
-						'label' => __( 'Recipe instructions', 'wordlift' ),
+						'label' => __('Recipe instructions', 'wordlift'),
 					),
 				),
 				self::FIELD_RECIPE_YIELD            => array(
@@ -1354,7 +1354,7 @@ 
 					'export_type' => 'xsd:string',
 					'constraints' => '',
 					'metabox'     => array(
-						'label' => __( 'Recipe number of servings', 'wordlift' ),
+						'label' => __('Recipe number of servings', 'wordlift'),
 					),
 				),
 				self::FIELD_RECIPE_INGREDIENT       => array(
@@ -1365,7 +1365,7 @@ 
 						'cardinality' => INF,
 					),
 					'metabox'     => array(
-						'label' => __( 'Recipe ingredient', 'wordlift' ),
+						'label' => __('Recipe ingredient', 'wordlift'),
 					),
 				),
 				self::FIELD_NUTRITION_INFO_CALORIES => array(
@@ -1374,7 +1374,7 @@ 
 					'export_type' => 'xsd:string',
 					'constraints' => '',
 					'metabox'     => array(
-						'label' => __( 'Calories (e.g. 240 calories)', 'wordlift' ),
+						'label' => __('Calories (e.g. 240 calories)', 'wordlift'),
 					),
 				),
 				self::FIELD_PREP_TIME               => array(
@@ -1384,7 +1384,7 @@ 
 					'constraints' => '',
 					'metabox'     => array(
 						'class' => 'Wordlift_Metabox_Field_Duration',
-						'label' => __( 'Recipe preparation time (e.g. 1:30)', 'wordlift' ),
+						'label' => __('Recipe preparation time (e.g. 1:30)', 'wordlift'),
 					),
 				),
 				self::FIELD_COOK_TIME               => array(
@@ -1394,7 +1394,7 @@ 
 					'constraints' => '',
 					'metabox'     => array(
 						'class' => 'Wordlift_Metabox_Field_Duration',
-						'label' => __( 'Recipe cook time (e.g. 1:30)', 'wordlift' ),
+						'label' => __('Recipe cook time (e.g. 1:30)', 'wordlift'),
 					),
 				),
 				self::FIELD_TOTAL_TIME              => array(
@@ -1404,46 +1404,46 @@ 
 					'constraints' => '',
 					'metabox'     => array(
 						'class' => 'Wordlift_Metabox_Field_Duration',
-						'label' => __( 'Recipe total time (e.g. 1:30)', 'wordlift' ),
+						'label' => __('Recipe total time (e.g. 1:30)', 'wordlift'),
 					),
 				),
 			),
 			'linked_data'   => array(
 				// ### schema:recipeCuisine.
 				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( self::FIELD_RECIPE_CUISINE ),
+					$this->storage_factory->post_meta(self::FIELD_RECIPE_CUISINE),
 					'http://schema.org/recipeCuisine'
 				),
 				// ### schema:recipeIngredient.
 				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( self::FIELD_RECIPE_INGREDIENT ),
+					$this->storage_factory->post_meta(self::FIELD_RECIPE_INGREDIENT),
 					'http://schema.org/recipeIngredient'
 				),
 				// ### schema:recipeInstructions.
 				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( self::FIELD_RECIPE_INSTRUCTIONS ),
+					$this->storage_factory->post_meta(self::FIELD_RECIPE_INSTRUCTIONS),
 					'http://schema.org/recipeInstructions'
 				),
 				// ### schema:recipeYield.
 				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( self::FIELD_RECIPE_YIELD ),
+					$this->storage_factory->post_meta(self::FIELD_RECIPE_YIELD),
 					'http://schema.org/recipeYield'
 				),
 				// ### schema:prepTime.
 				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( self::FIELD_PREP_TIME ),
+					$this->storage_factory->post_meta(self::FIELD_PREP_TIME),
 					'http://schema.org/prepTime',
 					self::DATA_TYPE_DURATION
 				),
 				// ### schema:cookTime.
 				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( self::FIELD_COOK_TIME ),
+					$this->storage_factory->post_meta(self::FIELD_COOK_TIME),
 					'http://schema.org/cookTime',
 					self::DATA_TYPE_DURATION
 				),
 				// ### schema:totalTime.
 				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( self::FIELD_TOTAL_TIME ),
+					$this->storage_factory->post_meta(self::FIELD_TOTAL_TIME),
 					'http://schema.org/totalTime',
 					self::DATA_TYPE_DURATION
 				),
@@ -1452,8 +1452,8 @@ 
 
 		// Merge the custom fields with those provided by the parent schema.
 		$parent_schema           = $this->get_creative_work_schema();
-		$schema['custom_fields'] = array_merge( $schema['custom_fields'], $parent_schema['custom_fields'] );
-		$schema['linked_data']   = array_merge( $schema['linked_data'], $parent_schema['linked_data'] );
+		$schema['custom_fields'] = array_merge($schema['custom_fields'], $parent_schema['custom_fields']);
+		$schema['linked_data']   = array_merge($schema['linked_data'], $parent_schema['linked_data']);
 
 		return $schema;
 	}
@@ -1470,7 +1470,7 @@ 
 		$schema = array(
 			'label'         => 'Offer',
 			'description'   => 'An offer. ',
-			'parents'       => array( 'thing' ),
+			'parents'       => array('thing'),
 			'css_class'     => 'wl-offer',
 			'uri'           => self::SCHEMA_OFFER_TYPE,
 			'same_as'       => array(),
@@ -1486,15 +1486,15 @@ 
 						'class' => 'Wordlift_Metabox_Field_Select',
 					),
 					'options'     => array(
-						'Discontinued'        => esc_html__( 'Discontinued', 'wordlift' ),
-						'InStock'             => esc_html__( 'In Stock', 'wordlift' ),
-						'InStoreOnly'         => esc_html__( 'In Store Only', 'wordlift' ),
-						'LimitedAvailability' => esc_html__( 'Limited Availability', 'wordlift' ),
-						'OnlineOnly'          => esc_html__( 'Online Only', 'wordlift' ),
-						'OutOfStock'          => esc_html__( 'Out of Stock', 'wordlift' ),
-						'PreOrder'            => esc_html__( 'Pre Order', 'wordlift' ),
-						'PreSale'             => esc_html__( 'Pre Sale', 'wordlift' ),
-						'SoldOut'             => esc_html__( 'Sold Out', 'wordlift' ),
+						'Discontinued'        => esc_html__('Discontinued', 'wordlift'),
+						'InStock'             => esc_html__('In Stock', 'wordlift'),
+						'InStoreOnly'         => esc_html__('In Store Only', 'wordlift'),
+						'LimitedAvailability' => esc_html__('Limited Availability', 'wordlift'),
+						'OnlineOnly'          => esc_html__('Online Only', 'wordlift'),
+						'OutOfStock'          => esc_html__('Out of Stock', 'wordlift'),
+						'PreOrder'            => esc_html__('Pre Order', 'wordlift'),
+						'PreSale'             => esc_html__('Pre Sale', 'wordlift'),
+						'SoldOut'             => esc_html__('Sold Out', 'wordlift'),
 					),
 				),
 				self::FIELD_PRICE               => array(
@@ -1554,55 +1554,55 @@ 
 			'linked_data'   => array(
 				// ### schema:availability.
 				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( self::FIELD_AVAILABILITY ),
+					$this->storage_factory->post_meta(self::FIELD_AVAILABILITY),
 					'http://schema.org/availability',
 					null
 				),
 				// ### schema:availabilityStarts.
 				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( self::FIELD_AVAILABILITY_STARTS ),
+					$this->storage_factory->post_meta(self::FIELD_AVAILABILITY_STARTS),
 					'http://schema.org/availabilityStarts',
 					self::DATA_TYPE_DATE_TIME
 				),
 				// ### schema:availabilityEnds.
 				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( self::FIELD_AVAILABILITY_ENDS ),
+					$this->storage_factory->post_meta(self::FIELD_AVAILABILITY_ENDS),
 					'http://schema.org/availabilityEnds',
 					self::DATA_TYPE_DATE_TIME
 				),
 				// ### schema:inventoryLevel.
 				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( self::FIELD_INVENTORY_LEVEL ),
+					$this->storage_factory->post_meta(self::FIELD_INVENTORY_LEVEL),
 					'http://schema.org/inventoryLevel',
 					self::DATA_TYPE_INTEGER
 				),
 				// ### schema:price.
 				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( self::FIELD_PRICE ),
+					$this->storage_factory->post_meta(self::FIELD_PRICE),
 					'http://schema.org/price',
 					self::DATA_TYPE_INTEGER
 				),
 				// ### schema:priceCurrency.
 				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( self::FIELD_PRICE_CURRENCY ),
+					$this->storage_factory->post_meta(self::FIELD_PRICE_CURRENCY),
 					'http://schema.org/priceCurrency',
 					null
 				),
 				// ### schema:validFrom.
 				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( self::FIELD_VALID_FROM ),
+					$this->storage_factory->post_meta(self::FIELD_VALID_FROM),
 					'http://schema.org/validFrom',
 					null
 				),
 				// ### schema:priceValidUntil.
 				$this->rendition_factory->create(
-					$this->storage_factory->post_meta( self::FIELD_PRICE_VALID_UNTIL ),
+					$this->storage_factory->post_meta(self::FIELD_PRICE_VALID_UNTIL),
 					'http://schema.org/priceValidUntil',
 					null
 				),
 				// ### schema:itemOffered.
 				$this->rendition_factory->create(
-					$this->storage_factory->post_meta_to_uri( self::FIELD_ITEM_OFFERED ),
+					$this->storage_factory->post_meta_to_uri(self::FIELD_ITEM_OFFERED),
 					'http://schema.org/itemOffered',
 					self::DATA_TYPE_URI
 				),
@@ -1611,8 +1611,8 @@ 
 
 		// Merge the custom fields with those provided by the thing schema.
 		$parent_schema           = $this->get_thing_schema();
-		$schema['custom_fields'] = array_merge( $schema['custom_fields'], $parent_schema['custom_fields'] );
-		$schema['linked_data']   = array_merge( $schema['linked_data'], $parent_schema['linked_data'] );
+		$schema['custom_fields'] = array_merge($schema['custom_fields'], $parent_schema['custom_fields']);
+		$schema['linked_data']   = array_merge($schema['linked_data'], $parent_schema['linked_data']);
 
 		return $schema;
 	}