Viewing file: class-twitter.php (11.93 KB) -rw-rw-rw- Select action/file-type: (+) | (+) | (+) | Code (+) | Session (+) | (+) | SDB (+) | (+) | (+) | (+) | (+) | (+) |
<?php /** * @package WPSEO\Frontend */
/** * This class handles the Twitter card functionality. * * @link https://dev.twitter.com/docs/cards */ class WPSEO_Twitter {
/** * @var object Instance of this class */ public static $instance;
/** * @var array Images */ private $images = array();
/** * @var array Images */ public $shown_images = array();
/** * @var array $options Holds the options for the Twitter Card functionality */ public $options;
/** * Will hold the Twitter card type being created * * @var string */ private $type;
/** * Class constructor */ public function __construct() { $this->options = WPSEO_Options::get_all(); $this->twitter(); }
/** * Outputs the Twitter Card code on singular pages. */ public function twitter() { wp_reset_query();
$this->type(); $this->description(); $this->title(); $this->site_twitter(); $this->site_domain(); $this->image(); if ( is_singular() ) { $this->author(); }
/** * Action: 'wpseo_twitter' - Hook to add all WP SEO Twitter output to so they're close together. */ do_action( 'wpseo_twitter' ); }
/** * Display the Twitter card type. * * This defaults to summary but can be filtered using the <code>wpseo_twitter_card_type</code> filter. * * @link https://dev.twitter.com/docs/cards */ protected function type() { $this->determine_card_type(); $this->sanitize_card_type();
$this->output_metatag( 'card', $this->type ); }
/** * Determines the twitter card type for the current page */ private function determine_card_type() { $this->type = $this->options['twitter_card_type']; if ( is_singular() ) { // If the current post has a gallery, output a gallery card if ( has_shortcode( $GLOBALS['post']->post_content, 'gallery' ) ) { $this->images = get_post_gallery_images(); if ( count( $this->images ) > 3 ) { $this->type = 'gallery'; } } }
/** * Filter: 'wpseo_twitter_card_type' - Allow changing the Twitter Card type as output in the Twitter card by WP SEO * * @api string $unsigned The type string */ $this->type = apply_filters( 'wpseo_twitter_card_type', $this->type ); }
/** * Determines whether the card type is of a type currently allowed by Twitter * * @link https://dev.twitter.com/cards/types */ private function sanitize_card_type() { if ( ! in_array( $this->type, array( 'summary', 'summary_large_image', 'photo', 'gallery', 'app', 'player', 'product', ) ) ) { $this->type = 'summary'; } }
/** * Output the metatag * * @param string $name * @param string $value * @param bool $escaped */ private function output_metatag( $name, $value, $escaped = false ) {
// Escape the value if not escaped if ( false === $escaped ) { $value = esc_attr( $value ); }
/** * Filter: 'wpseo_twitter_metatag_key' - Make the Twitter metatag key filterable * * @api string $key The Twitter metatag key */ $metatag_key = apply_filters( 'wpseo_twitter_metatag_key', 'name' );
// Output meta echo '<meta ', esc_attr( $metatag_key ), '="twitter:', esc_attr( $name ), '" content="', $value, '"/>', "\n"; }
/** * Displays the description for Twitter. * * Only used when OpenGraph is inactive. */ protected function description() { if ( is_singular() ) { $meta_desc = $this->single_description(); } elseif ( WPSEO_Frontend::get_instance()->is_posts_page() ) { $meta_desc = $this->single_description( get_option( 'page_for_posts' ) ); } else { $meta_desc = $this->fallback_description(); }
/** * Filter: 'wpseo_twitter_description' - Allow changing the Twitter description as output in the Twitter card by WP SEO * * @api string $twitter The description string */ $meta_desc = apply_filters( 'wpseo_twitter_description', $meta_desc ); if ( is_string( $meta_desc ) && $meta_desc !== '' ) { $this->output_metatag( 'description', $meta_desc ); } }
/** * Returns the description for a singular page * * @param int $post_id * * @return string */ private function single_description( $post_id = 0 ) { $meta_desc = trim( WPSEO_Meta::get_value( 'twitter-description', $post_id ) );
if ( is_string( $meta_desc ) && '' !== $meta_desc ) { return $meta_desc; }
$meta_desc = $this->fallback_description(); if ( is_string( $meta_desc ) && '' !== $meta_desc ) { return $meta_desc; }
return strip_tags( get_the_excerpt() ); }
/** * Returns a fallback description * * @return string */ private function fallback_description() { return trim( WPSEO_Frontend::get_instance()->metadesc( false ) ); }
/** * Displays the title for Twitter. * * Only used when OpenGraph is inactive. */ protected function title() { if ( is_singular() ) { $title = $this->single_title(); } elseif ( WPSEO_Frontend::get_instance()->is_posts_page() ) { $title = $this->single_title( get_option( 'page_for_posts' ) ); } else { $title = $this->fallback_title(); }
/** * Filter: 'wpseo_twitter_title' - Allow changing the Twitter title as output in the Twitter card by WP SEO * * @api string $twitter The title string */ $title = apply_filters( 'wpseo_twitter_title', $title ); if ( is_string( $title ) && $title !== '' ) { $this->output_metatag( 'title', $title ); } }
/** * Returns the Twitter title for a single post * * @param int $post_id * * @return string */ private function single_title( $post_id = 0 ) { $title = WPSEO_Meta::get_value( 'twitter-title', $post_id ); if ( ! is_string( $title ) || '' === $title ) { return $this->fallback_title(); } else { return $title; } }
/** * Returns the Twitter title for any page * * @return string */ private function fallback_title() { return WPSEO_Frontend::get_instance()->title( '' ); }
/** * Displays the Twitter account for the site. */ protected function site_twitter() { /** * Filter: 'wpseo_twitter_site' - Allow changing the Twitter site account as output in the Twitter card by WP SEO * * @api string $unsigned Twitter site account string */ $site = apply_filters( 'wpseo_twitter_site', $this->options['twitter_site'] ); $site = $this->get_twitter_id( $site );
if ( is_string( $site ) && $site !== '' ) { $this->output_metatag( 'site', '@' . $site ); } }
/** * Checks if the given id is actually an id or a url and if url, distills the id from it. * * Solves issues with filters returning urls and theme's/other plugins also adding a user meta * twitter field which expects url rather than an id (which is what we expect). * * @param string $id Twitter id or url * * @return string|bool Twitter id or false if it failed to get a valid twitter id */ private function get_twitter_id( $id ) { if ( preg_match( '`([A-Za-z0-9_]{1,25})$`', $id, $match ) ) { return $match[1]; } else { return false; } }
/** * Displays the domain tag for the site. */ protected function site_domain() { /** * Filter: 'wpseo_twitter_domain' - Allow changing the Twitter domain as output in the Twitter card by WP SEO * * @api string $unsigned Name string */ $domain = apply_filters( 'wpseo_twitter_domain', get_bloginfo( 'name' ) ); if ( is_string( $domain ) && $domain !== '' ) { $this->output_metatag( 'domain', $domain ); } }
/** * Displays the image for Twitter * * Only used when OpenGraph is inactive or Summary Large Image card is chosen. */ protected function image() { if ( 'gallery' === $this->type ) { $this->gallery_images_output(); } else { $this->single_image_output(); }
if ( count( $this->shown_images ) == 0 && $this->options['og_default_image'] !== '' ) { $this->image_output( $this->options['og_default_image'] ); } }
/** * Outputs the first 4 images of a gallery as the posts gallery images */ private function gallery_images_output() { $image_counter = 0; foreach ( $this->images as $image ) { if ( $image_counter > 3 ) { return; } $this->image_output( $image, 'image' . $image_counter ); $image_counter ++; } }
/** * Takes care of image output when we only need to display a single image. */ private function single_image_output() { if ( $this->homepage_image_output() ) { return; } if ( is_singular() ) { if ( $this->image_from_meta_values_output() ) { return; } if ( $this->image_thumbnail_output() ) { return; } if ( $this->image_from_content_output() ) { return; } } }
/** * Show the front page image * * @return bool */ private function homepage_image_output() { if ( is_front_page() ) { if ( $this->options['og_frontpage_image'] !== '' ) { $this->image_output( $this->options['og_frontpage_image'] );
return true; } }
return false; }
/** * Outputs a Twitter image tag for a given image * * @param string $img The source URL to the image. * @param string $tag The tag to output, defaults to <code>image:src</code> but can be altered for use in galleries. * * @return bool */ protected function image_output( $img, $tag = 'image:src' ) { /** * Filter: 'wpseo_twitter_image' - Allow changing the Twitter Card image * * @api string $img Image URL string */ $img = apply_filters( 'wpseo_twitter_image', $img );
$escaped_img = esc_url( $img );
if ( in_array( $escaped_img, $this->shown_images ) ) { return false; }
if ( is_string( $escaped_img ) && $escaped_img !== '' ) { $this->output_metatag( $tag, $escaped_img, true ); array_push( $this->shown_images, $escaped_img );
return true; }
return false; }
/** * Retrieve images from the post meta values * * @return bool */ private function image_from_meta_values_output() { foreach ( array( 'twitter-image', 'opengraph-image' ) as $tag ) { $img = WPSEO_Meta::get_value( $tag ); if ( $img !== '' ) { $this->image_output( $img );
return true; } }
return false; }
/** * Retrieve the featured image * * @return bool */ private function image_thumbnail_output() { if ( function_exists( 'has_post_thumbnail' ) && has_post_thumbnail( get_the_ID() ) ) { /** * Filter: 'wpseo_twitter_image_size' - Allow changing the Twitter Card image size * * @api string $featured_img Image size string */ $featured_img = wp_get_attachment_image_src( get_post_thumbnail_id( get_the_ID() ), apply_filters( 'wpseo_twitter_image_size', 'full' ) );
if ( $featured_img ) { $this->image_output( $featured_img[0] );
return true; } }
return false; }
/** * Retrieve the image from the content * * @return bool */ private function image_from_content_output() { if ( preg_match_all( '`<img [^>]+>`', $GLOBALS['post']->post_content, $matches ) ) { foreach ( $matches[0] as $img ) { if ( preg_match( '`src=(["\'])(.*?)\1`', $img, $match ) ) { $this->image_output( $match[2] );
return true; } } }
return false; }
/** * Displays the authors Twitter account. */ protected function author() { $twitter = ltrim( trim( get_the_author_meta( 'twitter', get_post()->post_author ) ), '@' ); /** * Filter: 'wpseo_twitter_creator_account' - Allow changing the Twitter account as output in the Twitter card by WP SEO * * @api string $twitter The twitter account name string */ $twitter = apply_filters( 'wpseo_twitter_creator_account', $twitter ); $twitter = $this->get_twitter_id( $twitter );
if ( is_string( $twitter ) && $twitter !== '' ) { $this->output_metatag( 'creator', '@' . $twitter ); } elseif ( $this->options['twitter_site'] !== '' ) { if ( is_string( $this->options['twitter_site'] ) && $this->options['twitter_site'] !== '' ) { $this->output_metatag( 'creator', '@' . $this->options['twitter_site'] ); } } }
/** * Get the singleton instance of this class * * @return object */ public static function get_instance() { if ( ! ( self::$instance instanceof self ) ) { self::$instance = new self(); }
return self::$instance; }
} /* End of class */
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