diff options
Diffstat (limited to 'plugins/jetpack/class.jetpack-twitter-cards.php')
| -rw-r--r-- | plugins/jetpack/class.jetpack-twitter-cards.php | 270 |
1 files changed, 270 insertions, 0 deletions
diff --git a/plugins/jetpack/class.jetpack-twitter-cards.php b/plugins/jetpack/class.jetpack-twitter-cards.php new file mode 100644 index 00000000..63d19917 --- /dev/null +++ b/plugins/jetpack/class.jetpack-twitter-cards.php @@ -0,0 +1,270 @@ +<?php + +/* Twitter Cards + * + * Hooks onto the Open Graph protocol and extends it by adding only the tags + * we need for twitter cards. + * + * @see /wp-content/blog-plugins/open-graph.php + * @see https://dev.twitter.com/cards/overview + */ +class Jetpack_Twitter_Cards { + + static function twitter_cards_tags( $og_tags ) { + global $post; + + /** + * Maximum alt text length. + * + * @see https://developer.twitter.com/en/docs/tweets/optimize-with-cards/overview/summary-card-with-large-image.html + */ + $alt_length = 420; + + if ( post_password_required() ) { + return $og_tags; + } + + /** This action is documented in class.jetpack.php */ + if ( apply_filters( 'jetpack_disable_twitter_cards', false ) ) { + return $og_tags; + } + + /* + * These tags apply to any page (home, archives, etc) + */ + + // If we have information on the author/creator, then include that as well + if ( ! empty( $post ) && ! empty( $post->post_author ) ) { + /** This action is documented in modules/sharedaddy/sharing-sources.php */ + $handle = apply_filters( 'jetpack_sharing_twitter_via', '', $post->ID ); + if ( ! empty( $handle ) && ! self::is_default_site_tag( $handle ) ) { + $og_tags['twitter:creator'] = self::sanitize_twitter_user( $handle ); + } + } + + $site_tag = self::site_tag(); + /** This action is documented in modules/sharedaddy/sharing-sources.php */ + $site_tag = apply_filters( 'jetpack_sharing_twitter_via', $site_tag, ( is_singular() ? $post->ID : null ) ); + /** This action is documented in modules/sharedaddy/sharing-sources.php */ + $site_tag = apply_filters( 'jetpack_twitter_cards_site_tag', $site_tag, $og_tags ); + if ( ! empty( $site_tag ) ) { + $og_tags['twitter:site'] = self::sanitize_twitter_user( $site_tag ); + } + + if ( ! is_singular() || ! empty( $og_tags['twitter:card'] ) ) { + /** + * Filter the default Twitter card image, used when no image can be found in a post. + * + * @module sharedaddy, publicize + * + * @since 5.9.0 + * + * @param string $str Default image URL. + */ + $image = apply_filters( 'jetpack_twitter_cards_image_default', '' ); + if ( ! empty( $image ) ) { + $og_tags['twitter:image'] = $image; + } + + return $og_tags; + } + + $the_title = get_the_title(); + if ( ! $the_title ) { + $the_title = get_bloginfo( 'name' ); + } + $og_tags['twitter:text:title'] = $the_title; + + /* + * The following tags only apply to single pages. + */ + + $card_type = 'summary'; + + // Try to give priority to featured images + if ( class_exists('Jetpack_PostImages') ) { + $featured = Jetpack_PostImages::from_thumbnail( $post->ID, 240, 240 ); + if ( !empty( $featured ) && count( $featured ) > 0 ) { + if ( (int) $featured[0]['src_width'] >= 280 && (int) $featured[0]['src_height'] >= 150 ) { + $card_type = 'summary_large_image'; + $og_tags['twitter:image'] = esc_url( add_query_arg( 'w', 640, $featured[0]['src'] ) ); + } else { + $og_tags['twitter:image'] = esc_url( add_query_arg( 'w', 240, $featured[0]['src'] ) ); + } + + // Add the alt tag if we have one. + if ( ! empty( $featured[0]['alt_text'] ) ) { + // Shorten it if it is too long. + if ( strlen( $featured[0]['alt_text'] ) > $alt_length ) { + $og_tags['twitter:image:alt'] = esc_attr( mb_substr( $featured[0]['alt_text'], 0, $alt_length ) . '…' ); + } else { + $og_tags['twitter:image:alt'] = esc_attr( $featured[0]['alt_text'] ); + } + } + } + } + + // Only proceed with media analysis if a featured image has not superseded it already. + if ( empty( $og_tags['twitter:image'] ) && empty( $og_tags['twitter:image:src'] ) ) { + if ( ! class_exists( 'Jetpack_Media_Summary' ) && defined('IS_WPCOM') && IS_WPCOM ) { + include( WP_CONTENT_DIR . '/lib/class.wpcom-media-summary.php' ); + } + + if ( ! class_exists( 'Jetpack_Media_Summary' ) ) { + jetpack_require_lib( 'class.media-summary' ); + } + + // Test again, class should already be auto-loaded in Jetpack. + // If not, skip extra media analysis and stick with a summary card + if ( class_exists( 'Jetpack_Media_Summary' ) ) { + $extract = Jetpack_Media_Summary::get( $post->ID ); + + if ( 'gallery' == $extract['type'] ) { + list( $og_tags, $card_type ) = self::twitter_cards_define_type_based_on_image_count( $og_tags, $extract ); + } elseif ( 'video' == $extract['type'] ) { + // Leave as summary, but with large pict of poster frame (we know those comply to Twitter's size requirements) + $card_type = 'summary_large_image'; + $og_tags['twitter:image'] = esc_url( add_query_arg( 'w', 640, $extract['image'] ) ); + } else { + list( $og_tags, $card_type ) = self::twitter_cards_define_type_based_on_image_count( $og_tags, $extract ); + } + } + } + + $og_tags['twitter:card'] = $card_type; + + // Make sure we have a description for Twitter, their validator isn't happy without some content (single space not valid). + if ( ! isset( $og_tags['og:description'] ) || '' == trim( $og_tags['og:description'] ) || __('Visit the post for more.', 'jetpack') == $og_tags['og:description'] ) { // empty( trim( $og_tags['og:description'] ) ) isn't valid php + $has_creator = ( ! empty($og_tags['twitter:creator']) && '@wordpressdotcom' != $og_tags['twitter:creator'] ) ? true : false; + if ( ! empty( $extract ) && 'video' == $extract['type'] ) { // use $extract['type'] since $card_type is 'summary' for video posts + /* translators: %s is the post author */ + $og_tags['twitter:description'] = ( $has_creator ) ? sprintf( __( 'Video post by %s.', 'jetpack' ), $og_tags['twitter:creator'] ) : __( 'Video post.', 'jetpack' ); + } else { + /* translators: %s is the post author */ + $og_tags['twitter:description'] = ( $has_creator ) ? sprintf( __( 'Post by %s.', 'jetpack' ), $og_tags['twitter:creator'] ) : __( 'Visit the post for more.', 'jetpack'); + } + } + + if ( empty( $og_tags['twitter:image'] ) && empty( $og_tags['twitter:image:src'] ) ) { + /** This action is documented in class.jetpack-twitter-cards.php */ + $image = apply_filters( 'jetpack_twitter_cards_image_default', '' ); + if ( ! empty( $image ) ) { + $og_tags['twitter:image'] = $image; + } + } + + return $og_tags; + } + + static function sanitize_twitter_user( $str ) { + return '@' . preg_replace( '/^@/', '', $str ); + } + + static function is_default_site_tag( $site_tag ) { + return in_array( $site_tag, array( '@wordpressdotcom', '@jetpack', 'wordpressdotcom', 'jetpack' ) ); + } + + static function prioritize_creator_over_default_site( $site_tag, $og_tags = array() ) { + if ( ! empty( $og_tags['twitter:creator'] ) && self::is_default_site_tag( $site_tag ) ) { + return $og_tags['twitter:creator']; + } + return $site_tag; + } + + static function twitter_cards_define_type_based_on_image_count( $og_tags, $extract ) { + $card_type = 'summary'; + $img_count = $extract['count']['image']; + + if ( empty( $img_count ) ) { + + // No images, use Blavatar as a thumbnail for the summary type. + if ( function_exists('blavatar_domain') ) { + $blavatar_domain = blavatar_domain( site_url() ); + if ( blavatar_exists( $blavatar_domain ) ) { + $og_tags['twitter:image'] = blavatar_url( $blavatar_domain, 'img', 240 ); + } + } + + // Second fall back, Site Logo + if ( empty( $og_tags['twitter:image'] ) && ( function_exists( 'jetpack_has_site_logo' ) && jetpack_has_site_logo() ) ) { + $og_tags['twitter:image'] = jetpack_get_site_logo( 'url' ); + } + + // Third fall back, Site Icon + if ( empty( $og_tags['twitter:image'] ) && has_site_icon() ) { + $og_tags['twitter:image'] = get_site_icon_url( '240' ); + } + + // Not falling back on Gravatar, because there's no way to know if we end up with an auto-generated one. + + } elseif ( $img_count && ( 'image' == $extract['type'] || 'gallery' == $extract['type'] ) ) { + // Test for $extract['type'] to limit to image and gallery, so we don't send a potential fallback image like a Gravatar as a photo post. + $card_type = 'summary_large_image'; + $og_tags['twitter:image'] = esc_url( add_query_arg( 'w', 1400, ( empty( $extract['images'] ) ) ? $extract['image'] : $extract['images'][0]['url'] ) ); + } + + return array( $og_tags, $card_type ); + } + + static function twitter_cards_output( $og_tag ) { + return ( false !== strpos( $og_tag, 'twitter:' ) ) ? preg_replace( '/property="([^"]+)"/', 'name="\1"', $og_tag ) : $og_tag; + } + + static function settings_init() { + add_settings_section( 'jetpack-twitter-cards-settings', 'Twitter Cards', '__return_false', 'sharing' ); + add_settings_field( + 'jetpack-twitter-cards-site-tag', + __( 'Twitter Site Tag', 'jetpack' ), + array( __CLASS__, 'settings_field' ), + 'sharing', + 'jetpack-twitter-cards-settings', + array( + 'label_for' => 'jetpack-twitter-cards-site-tag', + ) + ); + } + + static function sharing_global_options() { + do_settings_fields( 'sharing', 'jetpack-twitter-cards-settings' ); + } + + static function site_tag() { + $site_tag = ( defined( 'IS_WPCOM' ) && IS_WPCOM ) ? + trim( get_option( 'twitter_via' ) ) : + Jetpack_Options::get_option_and_ensure_autoload( 'jetpack-twitter-cards-site-tag', '' ); + if ( empty( $site_tag ) ) { + if ( defined( 'IS_WPCOM' ) && IS_WPCOM ) { + return 'wordpressdotcom'; + } else { + return; + } + } + return $site_tag; + } + + static function settings_field() { + wp_nonce_field( 'jetpack-twitter-cards-settings', 'jetpack_twitter_cards_nonce', false ); + ?> + <input type="text" id="jetpack-twitter-cards-site-tag" class="regular-text" name="jetpack-twitter-cards-site-tag" value="<?php echo esc_attr( get_option( 'jetpack-twitter-cards-site-tag' ) ); ?>" /> + <p class="description" style="width: auto;"><?php esc_html_e( 'The Twitter username of the owner of this site\'s domain.', 'jetpack' ); ?></p> + <?php + } + + static function settings_validate() { + if ( wp_verify_nonce( $_POST['jetpack_twitter_cards_nonce'], 'jetpack-twitter-cards-settings' ) ) { + update_option( 'jetpack-twitter-cards-site-tag', trim( ltrim( strip_tags( $_POST['jetpack-twitter-cards-site-tag'] ), '@' ) ) ); + } + } + + static function init() { + add_filter( 'jetpack_open_graph_tags', array( __CLASS__, 'twitter_cards_tags' ) ); + add_filter( 'jetpack_open_graph_output', array( __CLASS__, 'twitter_cards_output' ) ); + add_filter( 'jetpack_twitter_cards_site_tag', array( __CLASS__, 'site_tag' ), -99 ); + add_filter( 'jetpack_twitter_cards_site_tag', array( __CLASS__, 'prioritize_creator_over_default_site' ), 99, 2 ); + add_action( 'admin_init', array( __CLASS__, 'settings_init' ) ); + add_action( 'sharing_global_options', array( __CLASS__, 'sharing_global_options' ) ); + add_action( 'sharing_admin_update', array( __CLASS__, 'settings_validate' ) ); + } +} + +Jetpack_Twitter_Cards::init(); |