forked from facebookarchive/wordpress
/
open-graph-protocol.php
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/
open-graph-protocol.php
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<?php
/**
* Output Open Graph protocol for consumption by Facebook services building a summary of the webpage.
*
* @since 1.1
*
* @link http://ogp.me/ Open Graph protocol
*/
class Facebook_Open_Graph_Protocol {
/**
* Base IRI of Open Graph protocol RDFa properties.
*
* @since 1.1
*
* @var string
*/
const OGP_NS = 'http://ogp.me/ns#';
/**
* Base IRI of Facebook RDFa properties.
*
* @since 1.1
*
* @var string
*/
const FB_NS = 'http://ogp.me/ns/fb#';
/**
* Base IRI of Open Graph protocol article object global properties.
*
* @since 1.1
*
* @var string
*/
const ARTICLE_NS = 'http://ogp.me/ns/article#';
/**
* Base IRI of Open Graph protocol profile object global properties.
*
* @since 1.1
*
* @var string
*/
const PROFILE_NS = 'http://ogp.me/ns/profile#';
/**
* Base IRI of Open Graph protocol video object global properties.
*
* @since 1.1
*
* @var string
*/
const VIDEO_NS = 'http://ogp.me/ns/video#';
/**
* Minimum edge of an acceptable Open Graph protocol image in whole pixels.
*
* @since 1.1.9
*
* @var int
*/
const MIN_IMAGE_DIMENSION = 200;
/**
* Only list the first N eligible Open Graph protocol images.
*
* Facebook helps a person choose one of three parsed images when a link is pasted into a message
* Other consumers of Open Graph protocol data (Google, Twitter, etc.) may index additional images; increase this number to trade-off speed for coverage
*
* @since 1.5
*
* @var int
*/
const MAX_IMAGE_COUNT = 3;
/**
* Recursively build RDFa <meta> elements used for Open Graph protocol.
*
* @since 1.0
*
* @param string $property whitespace separated list of CURIEs placed in a property attribute
* @param mixed content attribute value for the given property. use an array for array property values or structured properties
* @return void
*/
public static function meta_elements( $property, $content ) {
if ( empty( $property ) || empty( $content ) )
return;
// array of property values or structured property
if ( is_array( $content ) ) {
// account for the special structured property of url which is equivalent to the root tag and sets up the structure
// must appear before other attributes
if ( isset( $content['url'] ) ) {
self::meta_elements( $property, $content['url'] );
unset( $content['url'] );
}
foreach( $content as $structured_property => $content_value ) {
// handle numeric keys from regular arrays
if ( ! is_string( $structured_property ) )
self::meta_elements( $property, $content_value );
else
self::meta_elements( $property . ':' . $structured_property, $content_value );
}
} else {
echo '<meta property="' . esc_attr( $property ) . '" content="' . esc_attr( $content ) . '"';
// do not use trailing slash if HTML5
// http://wiki.whatwg.org/wiki/FAQ#Should_I_close_empty_elements_with_.2F.3E_or_.3E.3F
if ( ! current_theme_supports('html5') )
echo ' /';
echo ">\n";
}
}
/**
* Clean post description text in preparation for Open Graph protocol description or Facebook post caption|description
*
* @since 1.1
*
* @uses strip_shortcodes()
* @uses wp_trim_words()
* @param string $description description text
* @return string description text passed through WordPress Core description cleaners, possibly trimmed
*/
public static function clean_description( $description, $trimmed = true ) {
$description = trim( $description );
if ( ! $description )
return '';
// basic filters from wp_trim_excerpt() that should apply to both excerpt and content
// note: the_content filter is so polluted with extra third-party stuff we purposely avoid to better represent page content
$description = strip_shortcodes( $description ); // remove any shortcodes that may exist, such as an image macro
$description = str_replace( ']]>', ']]>', $description );
$description = trim( $description );
if ( ! $description )
return '';
if ( $trimmed ) {
// use the built-in WordPress function for localized support of words vs. characters
// pass in customizations based on WordPress with publisher overrides
$description = wp_trim_words(
$description,
apply_filters( 'facebook_excerpt_length', apply_filters( 'excerpt_length', 55 ) ), // standard excerpt length, which may be customized by the publisher via the core filter, passed through another filter for our context
apply_filters( 'facebook_excerpt_more', __( '…' ) ) // filter the wp_trim_words default for publisher customization
);
} else {
$description = wp_strip_all_tags( $description );
}
if ( $description )
return $description;
return '';
}
/**
* Convert full IRI Open Graph protocol values to CURIE prefixed values
* Mapping CURIEs is presumed to occur in a parent element of the group of <meta>s
*
* @since 1.1.6
* @link http://www.w3.org/TR/rdfa-syntax/#s_curies RDFa 1.1 Core CURIEs
* @param array $ogp associative array of full IRI key and OGP value
* @return array associative array of full IRI replaced with prefix where mapped and the same OGP value passed in
*/
public static function prefixed_properties( $ogp ) {
global $facebook_loader;
if ( ! is_array( $ogp ) || empty( $ogp ) )
return array();
/**
* Map RDFa Core CURIEs and prefixes
*
* @since 1.1.6
*
* @param array {
* @type string RDFa CURIE
* @type array 'prefix' abbreviation recognized without a prefix mapping on a parent element
* }
*/
$curies = apply_filters( 'facebook_rdfa_mappings', array(
self::OGP_NS => array( 'prefix' => 'og' ),
self::FB_NS => array( 'prefix' => 'fb' ),
self::ARTICLE_NS => array( 'prefix' => 'article' ),
self::PROFILE_NS => array( 'prefix' => 'profile' ),
'http://ogp.me/ns/book#' => array( 'prefix' => 'book' ),
'http://ogp.me/ns/business#' => array( 'prefix' => 'business' ),
'http://ogp.me/ns/event#' => array( 'prefix' => 'event' ),
'http://ogp.me/ns/fitness#' => array( 'prefix' => 'fitness' ),
'http://ogp.me/ns/music#' => array( 'prefix' => 'music' ),
'http://ogp.me/ns/product#' => array( 'prefix' => 'product' ),
'http://ogp.me/ns/restaurant#' => array( 'prefix' => 'restaurant' ),
self::VIDEO_NS => array( 'prefix' => 'video' )
) );
if ( isset( $facebook_loader->credentials['app_namespace'] ) ) {
$app_ns_url = esc_url_raw( 'http://ogp.me/ns/fb/' . $facebook_loader->credentials['app_namespace'] . '#', array( 'http' ) );
if ( $app_ns_url && ! isset( $curies[$app_ns_url] ) )
$curies[$app_ns_url] = array( 'prefix' => $facebook_loader->credentials['app_namespace'] );
}
foreach ( $curies as $reference => $properties ) {
if ( ! isset( $properties['prefix'] ) ) {
unset( $curies[$reference] );
continue;
}
$properties['key_length'] = strlen( $reference );
$curies[$reference] = $properties;
}
$ogp_prefixed = array();
foreach ( $ogp as $property => $value ) {
$prefixed_property_set = false;
$property_length = strlen( $property );
foreach ( $curies as $reference => $properties ) {
if ( $property_length > $properties['key_length'] && substr_compare( $property, $reference, 0, $properties['key_length'] ) === 0 ) {
$ogp_prefixed[ $properties['prefix'] . ':' . substr( $property , $properties['key_length'] ) ] = $value;
$prefixed_property_set = true;
break;
}
}
unset( $property_length );
// pass through unmapped values
if ( ! $prefixed_property_set )
$ogp_prefixed[$property] = $value;
unset( $prefixed_property_set );
}
return $ogp_prefixed;
}
/**
* Add Open Graph protocol markup to <head>
* We use full IRIs for consistent mapping between mapped CURIE prefixes defined in a parent element and self-contained properties using a full IRI
*
* @since 1.0
*
* @link http://www.w3.org/TR/rdfa-syntax/#s_curieprocessing RDFa Core 1.1 CURIE and IRI processing
* @global stdClass|WP_Post $post WordPress post object for the current view
* @global Facebook_Loader $facebook_loader
* @return void
*/
public static function add_og_protocol() {
global $post, $facebook_loader;
$meta_tags = array(
self::OGP_NS . 'site_name' => get_bloginfo( 'name' ),
self::OGP_NS . 'type' => 'website'
);
if ( isset( $facebook_loader ) ) {
if ( isset( $facebook_loader->locale ) )
$meta_tags[ self::OGP_NS . 'locale' ] = $facebook_loader->locale;
if ( isset( $facebook_loader->credentials ) && isset( $facebook_loader->credentials['app_id'] ) && $facebook_loader->credentials['app_id'] )
$meta_tags[ self::FB_NS . 'app_id' ] = $facebook_loader->credentials['app_id'];
}
if ( is_home() || is_front_page() ) {
$meta_tags[ self::OGP_NS . 'title' ] = get_bloginfo( 'name' );
$meta_tags[ self::OGP_NS . 'description' ] = get_bloginfo( 'description' );
$meta_tags[ self::OGP_NS . 'url' ] = home_url();
} else if ( is_singular() && empty( $post->post_password ) ) {
setup_postdata( $post );
$post_type = get_post_type( $post );
/**
* Canonical URL for the singular page.
*
* @since 1.1.6
* @param string absolute URI of the current post context
*/
$meta_tags[ self::OGP_NS . 'url' ] = apply_filters( 'facebook_rel_canonical', get_permalink( $post->ID ) );
if ( post_type_supports( $post_type, 'title' ) )
$meta_tags[ self::OGP_NS . 'title' ] = get_the_title();
if ( post_type_supports( $post_type, 'excerpt' ) ) {
$description = '';
// did the publisher specify a custom excerpt? use it
if ( ! empty( $post->post_excerpt ) )
$description = apply_filters( 'get_the_excerpt', $post->post_excerpt );
else
$description = $post->post_content;
$description = self::clean_description( $description );
if ( $description )
$meta_tags[ self::OGP_NS . 'description' ] = $description;
}
$meta_tags[ self::OGP_NS . 'type' ] = self::get_post_og_type( $post );
$images = self::get_og_images( $post );
if ( ! empty( $images ) )
$meta_tags[ self::OGP_NS . 'image' ] = array_values( $images );
unset( $images );
if ( $meta_tags[ self::OGP_NS . 'type' ] === 'article' ) {
// add article-specific properties
$meta_tags = array_merge( $meta_tags, self::get_article_properties( $post ) );
} else if ( $meta_tags[ self::OGP_NS . 'type' ] === 'video.other' ) {
// attempt to declare a video or videos
$videos = self::get_og_videos( $post );
if ( ! empty( $videos ) ) {
$videos = array_values( $videos );
if ( count( $videos ) === 1 ) {
$video = array_shift( $videos );
if ( $video && isset( $video[ self::VIDEO_NS ] ) ) {
foreach( $video[self::VIDEO_NS] as $property => $value ) {
$meta_tags[ self::VIDEO_NS . $property ] = $value;
}
unset( $video[ self::VIDEO_NS ] );
}
$meta_tags[ self::OGP_NS . 'video' ] = array( $video );
unset( $video );
} else {
$videos_only = array();
foreach( $videos as $video ) {
unset( $video[self::VIDEO_NS] );
$videos_only[] = $video;
}
$meta_tags[ self::OGP_NS . 'video' ] = $videos_only;
unset( $videos_only );
}
}
unset( $videos );
if ( empty( $meta_tags[ self::OGP_NS . 'video' ] ) ) {
// try to find well-known and easily mapped video provider WP_Embeds
$videos = self::get_embed_videos( $post );
if ( ! empty( $videos ) ) {
foreach( $videos as $video_url => $video ) {
if ( empty( $video ) )
continue;
if ( isset( $video['image'] ) ) {
$meta_tags[ self::OGP_NS . 'image' ][] = $video['image'];
unset( $video['image'] );
}
$meta_tags[ self::OGP_NS . 'video' ] = array_values( $video );
}
}
unset( $videos );
}
}
// include MP3s for audio post formats
if ( has_post_format( 'audio', $post ) ) {
$audios = self::get_og_audio( $post );
if ( ! empty( $audios ) )
$meta_tags[ self::OGP_NS . 'audio' ] = array_values( $audios );
unset( $audios );
}
if ( post_type_supports( $post_type, 'author' ) && isset( $post->post_author ) ) {
// Facebook user helper
if ( ! class_exists( 'Facebook_User' ) )
require_once( $facebook_loader->plugin_directory . 'facebook-user.php' );
$facebook_user_data = Facebook_User::get_user_meta( $post->post_author, 'fb_data', true );
$author_fbid = '';
if ( is_array( $facebook_user_data ) && isset( $facebook_user_data['fb_uid'] ) )
$author_fbid = $facebook_user_data['fb_uid'];
unset( $facebook_user_data );
if ( $author_fbid ) {
$meta_tags[ self::FB_NS . 'profile_id' ] = $author_fbid;
// adding an fb:admin grants comment moderation permissions for Comment Box
if ( get_option( 'facebook_comments_enabled' ) && user_can( $post->post_author, 'moderate_comments' ) ) {
if ( ! class_exists( 'Facebook_Comments' ) )
require_once( $facebook_loader->plugin_directory . 'social-plugins/class-facebook-comments.php' );
if ( Facebook_Comments::comments_enabled_for_post_type( $post ) )
$meta_tags[ self::FB_NS . 'admins' ] = $author_fbid;
}
}
unset( $author_fbid );
}
} else if ( is_author() ) {
$author = get_queried_object();
if ( $author && isset( $author->ID ) ) {
$author_id = $author->ID;
$meta_tags[ self::OGP_NS . 'type' ] = 'profile';
$meta_tags[ self::OGP_NS . 'title' ] = get_the_author_meta( 'display_name', $author_id );
$meta_tags[ self::OGP_NS . 'url' ] = get_author_posts_url( get_the_author_meta( 'ID', $author_id ) );
$meta_tags[ self::PROFILE_NS . 'first_name' ] = get_the_author_meta( 'first_name', $author_id );
$meta_tags[ self::PROFILE_NS . 'last_name'] = get_the_author_meta( 'last_name', $author_id );
$description = self::clean_description( get_the_author_meta( 'description', $author_id ) );
if ( $description )
$meta_tags[ self::OGP_NS . 'description'] = $description;
// Facebook user helper
if ( ! class_exists( 'Facebook_User' ) )
require_once( $facebook_loader->plugin_directory . 'facebook-user.php' );
$facebook_user_data = Facebook_User::get_user_meta( $author_id, 'fb_data', true );
if ( is_array( $facebook_user_data ) && isset( $facebook_user_data['fb_uid'] ) )
$meta_tags[ self::FB_NS . 'profile_id' ] = $facebook_user_data['fb_uid'];
unset( $facebook_user_data );
// no need to show username if there is only one
if ( is_multi_author() )
$meta_tags[ self::PROFILE_NS . 'username' ] = get_the_author_meta( 'login', $author_id );
}
unset( $author );
} else if ( is_page() ) {
$meta_tags[ self::OGP_NS . 'type' ] = 'article';
$meta_tags[ self::OGP_NS . 'title' ] = get_the_title();
// duplicate_hook
$meta_tags[ self::OGP_NS . 'url' ] = apply_filters( 'facebook_rel_canonical', get_permalink() );
}
/**
* Customize Open Graph protocol for the site or page before output.
*
* Add, change, and delete Open Graph protocol values used to summarize a link shared on Facebook and create new Open Graph objects.
*
* @since 1.0
* @param array $meta_tags {
* Open Graph protocol values to be output
*
* @type string Full IRI RDFa Core property
* @type mixed property value or multiple values
* }
* @param stdClass|WP_Post $post the current post global if set
*/
$meta_tags = apply_filters( 'fb_meta_tags', $meta_tags, $post );
/**
* Control auto-prefixing or full IRI RDFa Core 1.1 properties output for the page.
*
* Use prefixed values (e.g. og:image) by default to maximize compatibility with indexers. Assumes prefix CURIE mappings will be set on <head> or <html> to properly map the prefixes or the publisher is not concerned with RDFa Core 1.1 compatibility and reserved prefixes.
*
* @since 1.1.6
* @param bool default true
*/
if ( apply_filters( 'facebook_ogp_prefixed', true ) )
$meta_tags = self::prefixed_properties( $meta_tags );
foreach ( $meta_tags as $property => $content ) {
self::meta_elements( $property, $content );
}
}
/**
* Classify the current post as an Open Graph object type.
*
* @since 1.5
*
* @link https://developers.facebook.com/docs/reference/opengraph/object-type/ Facebook global object types
* @param stdClass|WP_Post $post the post to classify
* @return string Open Graph protocol type property value
*/
public static function get_post_og_type( $post ) {
$og_type = 'website';
if ( ! ( $post && isset( $post->ID ) ) )
return $og_type;
// treat video post format as OG type video
if ( has_post_format( 'video', $post ) )
$og_type = 'video.other';
else if ( get_post_type( $post ) === 'post' )
$og_type = 'article';
$og_type = apply_filters( 'facebook_og_type', $og_type, $post );
if ( ! $og_type )
$og_type = 'website';
return $og_type;
}
/**
* Map WordPress post data to Open Graph article object properties.
*
* @since 1.5
*
* @param stdClass|WP_Post $post the post of interest
* @return array {
* Associative array of OGP properties and values related to the post
*
* @type string Full IRI Open Graph protocol property
* @type string|array Open Graph protocol property value
* }
*/
public static function get_article_properties( $post ) {
global $facebook_loader;
$ogp = array(
self::ARTICLE_NS . 'published_time' => date( 'c', strtotime( $post->post_date_gmt ) ),
self::ARTICLE_NS . 'modified_time' => date( 'c', strtotime( $post->post_modified_gmt ) )
);
if ( post_type_supports( get_post_type( $post ), 'author' ) && isset( $post->post_author ) ) {
if ( ! class_exists( 'Facebook_User' ) )
require_once( $facebook_loader->plugin_directory . 'facebook-user.php' );
$facebook_user_data = Facebook_User::get_user_meta( $post->post_author, 'fb_data', true );
if ( is_array( $facebook_user_data ) && isset( $facebook_user_data['link'] ) )
$ogp[ self::ARTICLE_NS . 'author' ] = $facebook_user_data['link'];
else
$ogp[ self::ARTICLE_NS . 'author' ] = get_author_posts_url( $post->post_author );
unset( $facebook_user_data );
}
$facebook_page = get_option( 'facebook_publish_page' );
if ( is_array( $facebook_page ) && isset( $facebook_page['link'] ) )
$ogp[ self::ARTICLE_NS . 'publisher' ] = $facebook_page['link'];
unset( $facebook_page );
// add the first category as a section. all other categories as tags
$cat_ids = get_the_category( $post->ID );
if ( ! empty( $cat_ids ) ) {
$no_category = apply_filters( 'the_category', __( 'Uncategorized' ) );
$cat = get_category( $cat_ids[0] );
if ( ! empty( $cat ) && isset( $cat->name ) && $cat->name !== $no_category )
$ogp[ self::ARTICLE_NS . 'section' ] = $cat->name;
// output the rest of the categories as tags
unset( $cat_ids[0] );
if ( ! empty( $cat_ids ) ) {
$ogp[ self::ARTICLE_NS . 'tag' ] = array();
foreach( $cat_ids as $cat_id ) {
$cat = get_category( $cat_id );
if ( isset( $cat->name ) && $cat->name !== $no_category )
$ogp[ self::ARTICLE_NS . 'tag' ][] = $cat->name;
unset( $cat );
}
}
}
// add tags. treat tags as lower priority than multiple categories
$tags = get_the_tags( $post->ID );
if ( $tags ) {
if ( ! isset( $ogp[ self::ARTICLE_NS . 'tag' ] ) )
$ogp[ self::ARTICLE_NS . 'tag' ] = array();
foreach ( $tags as $tag ) {
$ogp[ self::ARTICLE_NS . 'tag' ][] = $tag->name;
}
}
return $ogp;
}
/**
* Extract Open Graph protocol image information from a WordPress image attachment.
*
* @since 1.5
*
* @uses wp_get_attachment_image_src()
* @param int $attachment_id post id of the attachment object
* @param string $size requested size. one of thumbnail, medium, large, or full
* @return array {
* Attachment converted into image, width, and height values or empty if no image data found or minimum requirements not met
*
* @type string 'url' Full URI of the attachment for the requested size
* @type int 'width' Width of the image in whole pixels
* @type int 'height' Height of the image in whole pixels
* }
*/
public static function attachment_to_og_image( $attachment_id, $size = 'full' ) {
if ( ! ( is_string( $size ) && $size ) )
$size = 'full';
$image = array();
list( $attachment_url, $attachment_width, $attachment_height ) = wp_get_attachment_image_src( $attachment_id, $size );
if ( empty( $attachment_url ) )
return $image;
$image['url'] = $attachment_url;
if ( ! empty( $attachment_width ) ) {
$image['width'] = absint( $attachment_width );
if ( ! $image['width'] )
unset( $image['width'] );
else if ( $image['width'] < self::MIN_IMAGE_DIMENSION )
return array();
}
if ( ! empty( $attachment_height ) ) {
$image['height'] = absint( $attachment_height );
if ( ! $image['height'] )
unset( $image['height'] );
else if ( $image['height'] < self::MIN_IMAGE_DIMENSION )
return array();
}
return $image;
}
/**
* Identify image attachments related to the post.
*
* Request the full size of the attachment, not necessarily the same as the size used in the post.
*
* @since 1.5
*
* @param stdClass|WP_Post $post WordPress post of interest
* @return array {
* Open Graph protocol image structured data
*
* @type string URL of the image
* @type array associative array of image data
* }
*/
public static function get_og_images( $post ) {
$og_images = array();
if ( ! $post || ! isset( $post->ID ) )
return $og_images;
// does current post type and the current theme support post thumbnails?
if ( post_type_supports( get_post_type( $post ), 'thumbnail' ) && function_exists( 'has_post_thumbnail' ) && has_post_thumbnail() ) {
list( $post_thumbnail_url, $post_thumbnail_width, $post_thumbnail_height ) = wp_get_attachment_image_src( get_post_thumbnail_id( $post->ID ), 'full' );
$image = self::attachment_to_og_image( get_post_thumbnail_id( $post->ID ) );
if ( isset( $image['url'] ) && ! isset( $og_images[ $image['url'] ] ) )
$og_images[ $image['url'] ] = $image;
unset( $image );
}
// get image attachments
if ( function_exists( 'get_attached_media' ) ) {
$images = get_attached_media( 'image', $post->ID );
if ( ! empty( $images ) ) {
foreach( $images as $i ) {
if ( ! isset( $i->ID ) )
continue;
$image = self::attachment_to_og_image( $i->ID );
if ( ! isset( $image['url'] ) || isset( $og_images[ $image['url'] ] ) )
continue;
$og_images[ $image['url'] ] = $image;
if ( count( $og_images ) === self::MAX_IMAGE_COUNT )
return $og_images;
}
}
unset( $images );
}
// test for WP_Embed handled images
if ( ! empty( $post->post_content ) ) {
// Instagram
preg_match_all( '#\s*http://instagr(\.am|am\.com)/p/(.*)/\s*#i', $post->post_content, $matches );
if ( isset( $matches[2] ) ) {
foreach( $matches[2] as $instagram_id ) {
$instagram_url = esc_url_raw( 'http://instagram.com/p/' . $instagram_id . '/media/?size=l', array( 'http' ) );
if ( ! $instagram_url || isset( $og_images[$instagram_url] ) )
continue;
$og_images[$instagram_url] = array( 'url' => $instagram_url );
unset( $instagram_url );
}
}
unset( $matches );
}
// add gallery content
if ( function_exists( 'get_post_galleries' ) ) {
// use get_post_galleries function from WP 3.6+
$galleries = get_post_galleries( $post, false );
foreach( $galleries as $gallery ) {
// use ids to request full-size image URI
if ( ! ( isset( $gallery['ids'] ) && $gallery['ids'] ) )
continue;
$gallery['ids'] = explode( ',', $gallery['ids'] );
foreach( $gallery['ids'] as $attachment_id ) {
$image = self::attachment_to_og_image( $attachment_id );
if ( ! isset( $image['url'] ) || isset( $og_images[ $image['url'] ] ) )
continue;
$og_images[ $image['url'] ] = $image;
if ( count( $og_images ) === self::MAX_IMAGE_COUNT )
return $og_images;
unset( $image );
}
}
unset( $galleries );
} else {
// extract full-size images from gallery shortcode
$og_images = self::gallery_images( $post, $og_images );
}
return $og_images;
}
/**
* Identify video attachments related to the post.
*
* Prefer SWF and MP4 videos.
*
* @since 1.5
*
* @param stdClass|WP_Post $post WordPress post of interest
* @return array {
* Array of associative arrays containing OGP video structured data
*
* @type string URL of the video
* @type array Open Graph protocol video properties with possible video object namespaced properties
* }
*/
public static function get_og_videos( $post ) {
$og_videos = array();
if ( ! $post )
return $og_videos;
if ( function_exists( 'get_attached_media' ) ) {
$videos = get_attached_media( 'video', $post->ID );
foreach( $videos as $video ) {
if ( ! isset( $video->ID ) )
continue;
$url = wp_get_attachment_url( $video->ID );
if ( ! $url || isset( $og_videos[ $url ] ) )
continue;
$og_video = array( 'url' => $url );
unset( $url );
if ( isset( $video->post_mime_type ) && $video->post_mime_type )
$og_video['type'] = $video->post_mime_type;
$meta = wp_get_attachment_metadata( $video->ID );
if ( is_array( $meta ) ) {
if ( isset( $meta['width'] ) && isset( $meta['height'] ) ) {
$meta['width'] = absint( $meta['width'] );
$meta['height'] = absint( $meta['height'] );
if ( $meta['width'] < self::MIN_IMAGE_DIMENSION || $meta['height'] < self::MIN_IMAGE_DIMENSION )
continue;
$og_video['width'] = $meta['width'];
$og_video['height'] = $meta['height'];
}
if ( isset( $meta['length'] ) ) {
$meta['length'] = absint( $meta['length'] );
if ( $meta['length'] > 0 )
$og_video[ self::VIDEO_NS ]['duration'] = $meta['length'];
}
}
unset( $meta );
$og_videos[ $og_video['url'] ] = $og_video;
unset( $og_video );
}
unset( $videos );
}
return $og_videos;
}
/**
* Convert popular video providers to SWF and image URLs
*
* @since 1.5.3
*
* @param stdClass|WP_Post $post WordPress post of interest
* @return array {
* Array of associative arrays containing OGP video structured data for WP_Embed autolinked providers
*
* @type string URL of the video
* @type array Open Graph protocol video properties with possible 'image' key containing an og:image strutured data array for the video
* }
*/
public static function get_embed_videos( $post ) {
$og_videos = array();
if ( ! ( isset( $post->post_content ) && $post->post_content ) )
return $og_videos;
// @see WP_Embed::autoembed()
preg_match_all( '|^\s*(https?://[^\s"]+)\s*$|im', $post->post_content, $embed_urls );
if ( ! isset( $embed_urls[1] ) )
return $og_videos;
$embed_urls = array_unique( $embed_urls[1], SORT_STRING );
foreach( $embed_urls as $embed_url ) {
if ( preg_match( '#^https?://www\.youtube\.com/watch\?(.*)#i', $embed_url, $matches ) ) {
parse_str( $matches[1], $youtube_parameters );
if ( isset( $youtube_parameters['v'] ) && $youtube_parameters['v'] )
$og_videos = self::youtube_video_to_open_graph( $youtube_parameters['v'], $og_videos );
unset( $youtube_parameters );
} else if ( preg_match( '#^http://youtu\.be/(.*)#i', $embed_url, $matches ) ) {
$og_videos = self::youtube_video_to_open_graph( $matches[1], $og_videos );
} else if ( preg_match( '#^https?://(www\.)?vimeo\.com/([0-9]+)\??#i', $embed_url, $matches ) ) {
$og_videos = self::vimeo_video_to_open_graph( $matches[2], $og_videos );
}
}
return $og_videos;
}
/**
* Identify MP3 (audio/mpeg) attachments related to the post.
*
* @since 1.5
*
* @param stdClass|WP_Post $post WordPress post of interest
* @return array {
* Array of associative arrays containing OGP audio structured data
*
* @type string URL of the audio file
* @type array Open Graph protocol audio properties
* }
*/
public static function get_og_audio( $post ) {
$og_audios = array();
if ( ! $post )
return $og_audios;
if ( function_exists( 'get_attached_media' ) ) {
$audios = get_attached_media( 'audio/mpeg', $post->ID );
foreach ( $audios as $audio ) {
$url = wp_get_attachment_url( $audio->ID );
if ( ! $url || isset( $og_audios[ $url ] ) )
continue;
$og_audio = array( 'url' => $url );
unset( $url );
if ( isset( $audio->post_mime_type ) && $audio->post_mime_type )
$og_audio['type'] = $audio->post_mime_type;
$og_audios[ $og_audio['url'] ] = $og_audio;
unset( $og_audio );
}
unset( $audios );
}
return $og_audios;
}
/**
* Find gallery shortcodes in the post. Build Open Graph protocol image results.
*
* Used if get_post_galleries() is not present (adds support for WordPress < 3.6).
*
* @since 1.1.9
*
* @param stdClass|WP_Post $post current post object
* @param array $existing_images add to an existing list of images. Check for duplication.
* @return array {
* Array of arrays containing Open Graph protocol image markup
*
* @type string URL of the image
* @type array Open Graph protocol image properties
* }
*/
public static function gallery_images( $post, $existing_images = array() ) {
global $shortcode_tags;
if ( ! is_array( $existing_images ) )
$existing_images = array();
$og_images = array();
if ( ! ( isset( $shortcode_tags['gallery'] ) && isset( $post->post_content ) && $post->post_content ) )
return $og_images;
$first_gallery = strpos( $post->post_content, '[gallery' );
if ( $first_gallery === false )
return $og_images;
// use regex finder with only the gallery shortcode
$old_shortcodes = $shortcode_tags;
$shortcode_tags = array( 'gallery' => $shortcode_tags['gallery'] );
// find all the gallery shortcodes in the post content
preg_match_all( '/' . get_shortcode_regex() . '/s', $post->post_content, $galleries, PREG_SET_ORDER, $first_gallery );
// reset
$shortcode_tags = $old_shortcodes;
foreach( $galleries as $gallery_shortcode ) {
// request the full-sized image
if ( empty( $gallery_shortcode[3] ) ) {
$gallery_shortcode[3] = ' size="full"';
} else {
// break it down
$parsed_attributes = shortcode_parse_atts( $gallery_shortcode[3] );
// add new attribute or override existing
$parsed_attributes['size'] = 'full';
// build it up again
$attr_str = '';
foreach ( $parsed_attributes as $attribute => $value ) {
$attr_str .= ' ' . $attribute . '="' . $value . '"';
}
unset( $parsed_attributes );
if ( $attr_str )
$gallery_shortcode[3] = $attr_str;
unset( $attr_str );
}
// pass the shortcode through all filters and actors
$gallery_html = do_shortcode_tag( $gallery_shortcode );
if ( ! $gallery_html )
continue;
$gallery_html = strip_tags( $gallery_html, '<img>' );
if ( ! $gallery_html )
continue;
$first_image = strpos( $gallery_html, '<img' );
if ( $first_image === false )
continue;
preg_match_all( '/<img[^>]+>/i', $gallery_html, $images, PREG_PATTERN_ORDER, $first_image );
unset( $gallery_html );
if ( ! ( is_array( $images ) && is_array( $images[0] ) ) )
continue;
$images = $images[0];
foreach ( $images as $image ) {
preg_match_all( '/(src|width|height)="([^"]*)"/i', $image, $image_attributes, PREG_SET_ORDER );
$og_image = array();
foreach( $image_attributes as $parsed_attributes ) {
if ( $parsed_attributes[1] === 'src' ) {
$url = esc_url_raw( wp_specialchars_decode( $parsed_attributes[2] ), array( 'http', 'https' ) );
if ( $url )
$og_image['url'] = $url;
unset( $url );
} else if ( $parsed_attributes[1] === 'width' || $parsed_attributes[1] === 'height' ) {
$pixels = absint( $parsed_attributes[2] );
if ( $pixels > 0 )
$og_image[ $parsed_attributes[1] ] = $pixels;
unset( $pixels );
}
}
if ( ! isset( $og_image['url'] ) || isset( $existing_images[ $og_image['url'] ] ) || ( isset( $og_image['width'] ) && $og_image['width'] < self::MIN_IMAGE_DIMENSION ) || ( isset( $og_image['height'] ) && $og_image['height'] < self::MIN_IMAGE_DIMENSION ) )
continue;
$existing_images[ $og_image['url'] ] = $og_image;
unset( $og_image );
if ( count( $existing_images ) === self::MAX_IMAGE_COUNT )
return $existing_images;
}
}
return $existing_images;
}
/**
* Build Open Graph protocol markup for a single YouTube video identifier.
*
* @since 1.5.3
*
* @link https://developers.google.com/youtube/player_parameters YouTube Embedded Player Parameters
* @param string $youtube_id YouTube video identifier
* @param array $exiting_videos Existing matched videos. Avoid duplication by comparing YouTube HTML embed URIs
* @return array Passed 'existing_videos' array with a possible YouTube video added
*/
public static function youtube_video_to_open_graph( $youtube_id, $og_videos = array() ) {
if ( ! is_array( $og_videos ) )
$og_videos = array();
if ( ! ( is_string( $youtube_id ) && $youtube_id ) )
return $og_videos;
$iframe_url = esc_url_raw( 'https://www.youtube.com/embed/' . $youtube_id . '?autoplay=1&rel=0', array( 'https' ) );
if ( ! $iframe_url || isset( $og_videos[ $iframe_url ] ) )
return $existing_videos;
$flash_url = esc_url_raw( 'https://www.youtube.com/v/' . $youtube_id . '?version=3&autoplay=1&rel=0', array( 'https' ) );
if ( ! $flash_url )
return $og_videos;
$og_videos[ $iframe_url ] = array(
'html' => array(
'url' => $iframe_url,
'type' => 'text/html'
),
'swf' => array(
'url' => $flash_url,
'type' => 'application/x-shockwave-flash'
)
);
$image_url = esc_url_raw( 'http://img.youtube.com/vi/' . $youtube_id . '/sddefault.jpg', array( 'http', 'https' ) );
if ( $image_url ) {
$og_videos[ $iframe_url ]['image'] = array( 'url' => $image_url );
}
return $og_videos;
}
/**
* Build Open Graph protocol markup for a single Vimeo video identifier.
*
* Note: this function does not query the Vimeo API and therefore does not include a thumbnail image for the video. For best results be sure to set your own og:image.
*