diff options
Diffstat (limited to 'plugins/jetpack/modules/lazy-images/lazy-images.php')
| -rw-r--r-- | plugins/jetpack/modules/lazy-images/lazy-images.php | 353 |
1 files changed, 0 insertions, 353 deletions
diff --git a/plugins/jetpack/modules/lazy-images/lazy-images.php b/plugins/jetpack/modules/lazy-images/lazy-images.php deleted file mode 100644 index befa5ec8..00000000 --- a/plugins/jetpack/modules/lazy-images/lazy-images.php +++ /dev/null @@ -1,353 +0,0 @@ -<?php - -class Jetpack_Lazy_Images { - private static $__instance = null; - - /** - * Singleton implementation - * - * @return object - */ - public static function instance() { - if ( is_null( self::$__instance ) ) { - self::$__instance = new Jetpack_Lazy_Images(); - } - - return self::$__instance; - } - - /** - * Registers actions - */ - private function __construct() { - if ( is_admin() ) { - return; - } - - /** - * Whether the lazy-images module should load. - * - * This filter is not prefixed with jetpack_ to provide a smoother migration - * process from the WordPress Lazy Load plugin. - * - * @module lazy-images - * - * @since 5.6.0 - * - * @param bool true Whether lazy image loading should occur. - */ - if ( ! apply_filters( 'lazyload_is_enabled', true ) ) { - return; - } - - if ( Jetpack_AMP_Support::is_amp_request() ) { - return; - } - - add_action( 'wp_head', array( $this, 'setup_filters' ), 9999 ); // we don't really want to modify anything in <head> since it's mostly all metadata - add_action( 'wp_enqueue_scripts', array( $this, 'enqueue_assets' ) ); - - // Do not lazy load avatar in admin bar - add_action( 'admin_bar_menu', array( $this, 'remove_filters' ), 0 ); - - add_filter( 'wp_kses_allowed_html', array( $this, 'allow_lazy_attributes' ) ); - add_action( 'wp_head', array( $this, 'add_nojs_fallback' ) ); - } - - public function setup_filters() { - add_filter( 'the_content', array( $this, 'add_image_placeholders' ), PHP_INT_MAX ); // run this later, so other content filters have run, including image_add_wh on WP.com - add_filter( 'post_thumbnail_html', array( $this, 'add_image_placeholders' ), PHP_INT_MAX ); - add_filter( 'get_avatar', array( $this, 'add_image_placeholders' ), PHP_INT_MAX ); - add_filter( 'widget_text', array( $this, 'add_image_placeholders' ), PHP_INT_MAX ); - add_filter( 'get_image_tag', array( $this, 'add_image_placeholders' ), PHP_INT_MAX); - add_filter( 'wp_get_attachment_image_attributes', array( __CLASS__, 'process_image_attributes' ), PHP_INT_MAX ); - } - - public function remove_filters() { - remove_filter( 'the_content', array( $this, 'add_image_placeholders' ), PHP_INT_MAX ); - remove_filter( 'post_thumbnail_html', array( $this, 'add_image_placeholders' ), PHP_INT_MAX ); - remove_filter( 'get_avatar', array( $this, 'add_image_placeholders' ), PHP_INT_MAX ); - remove_filter( 'widget_text', array( $this, 'add_image_placeholders' ), PHP_INT_MAX ); - remove_filter( 'get_image_tag', array( $this, 'add_image_placeholders' ), PHP_INT_MAX); - remove_filter( 'wp_get_attachment_image_attributes', array( __CLASS__, 'process_image_attributes' ), PHP_INT_MAX ); - } - - /** - * Ensure that our lazy image attributes are not filtered out of image tags. - * - * @param array $allowed_tags The allowed tags and their attributes. - * @return array - */ - public function allow_lazy_attributes( $allowed_tags ) { - if ( ! isset( $allowed_tags['img'] ) ) { - return $allowed_tags; - } - - // But, if images are allowed, ensure that our attributes are allowed! - $img_attributes = array_merge( $allowed_tags['img'], array( - 'data-lazy-src' => 1, - 'data-lazy-srcset' => 1, - 'data-lazy-sizes' => 1, - ) ); - - $allowed_tags['img'] = $img_attributes; - - return $allowed_tags; - } - - public function add_image_placeholders( $content ) { - // Don't lazyload for feeds, previews - if ( is_feed() || is_preview() ) { - return $content; - } - - // Don't lazy-load if the content has already been run through previously - if ( false !== strpos( $content, 'data-lazy-src' ) ) { - return $content; - } - - // This is a pretty simple regex, but it works - $content = preg_replace_callback( '#<(img)([^>]+?)(>(.*?)</\\1>|[\/]?>)#si', array( __CLASS__, 'process_image' ), $content ); - - return $content; - } - - /** - * Returns true when a given string of classes contains a class signifying lazy images - * should not process the image. - * - * @since 5.9.0 - * - * @param string $classes A string of space-separated classes. - * @return bool - */ - public static function should_skip_image_with_blacklisted_class( $classes ) { - $blacklisted_classes = array( - 'skip-lazy', - 'gazette-featured-content-thumbnail', - ); - - /** - * Allow plugins and themes to tell lazy images to skip an image with a given class. - * - * @module lazy-images - * - * @since 5.9.0 - * - * @param array An array of strings where each string is a class. - */ - $blacklisted_classes = apply_filters( 'jetpack_lazy_images_blacklisted_classes', $blacklisted_classes ); - - if ( ! is_array( $blacklisted_classes ) || empty( $blacklisted_classes ) ) { - return false; - } - - foreach ( $blacklisted_classes as $class ) { - if ( false !== strpos( $classes, $class ) ) { - return true; - } - } - - return false; - } - - /** - * Processes images in content by acting as the preg_replace_callback - * - * @since 5.6.0 - * - * @param array $matches - * - * @return string The image with updated lazy attributes - */ - static function process_image( $matches ) { - $old_attributes_str = $matches[2]; - $old_attributes_kses_hair = wp_kses_hair( $old_attributes_str, wp_allowed_protocols() ); - - if ( empty( $old_attributes_kses_hair['src'] ) ) { - return $matches[0]; - } - - $old_attributes = self::flatten_kses_hair_data( $old_attributes_kses_hair ); - - // If we didn't add lazy attributes, just return the original image source. - if ( ! empty( $old_attributes['class'] ) && false !== strpos( $old_attributes['class'], 'jetpack-lazy-image' ) ) { - return $matches[0]; - } - - $new_attributes = self::process_image_attributes( $old_attributes ); - $new_attributes_str = self::build_attributes_string( $new_attributes ); - - return sprintf( '<img %1$s><noscript>%2$s</noscript>', $new_attributes_str, $matches[0] ); - } - - /** - * Given an array of image attributes, updates the `src`, `srcset`, and `sizes` attributes so - * that they load lazily. - * - * @since 5.7.0 - * - * @param array $attributes - * - * @return array The updated image attributes array with lazy load attributes - */ - static function process_image_attributes( $attributes ) { - if ( empty( $attributes['src'] ) ) { - return $attributes; - } - - if ( ! empty( $attributes['class'] ) && self::should_skip_image_with_blacklisted_class( $attributes['class'] ) ) { - return $attributes; - } - - /** - * Allow plugins and themes to conditionally skip processing an image via its attributes. - * - * @module-lazy-images - * - * @deprecated 6.5.0 Use jetpack_lazy_images_skip_image_with_attributes instead. - * - * @since 5.9.0 - * - * @param bool Default to not skip processing the current image. - * @param array An array of attributes via wp_kses_hair() for the current image. - */ - if ( apply_filters( 'jetpack_lazy_images_skip_image_with_atttributes', false, $attributes ) ) { - return $attributes; - } - - /** - * Allow plugins and themes to conditionally skip processing an image via its attributes. - * - * @module-lazy-images - * - * @since 6.5.0 Filter name was updated from jetpack_lazy_images_skip_image_with_atttributes to correct typo. - * @since 5.9.0 - * - * @param bool Default to not skip processing the current image. - * @param array An array of attributes via wp_kses_hair() for the current image. - */ - if ( apply_filters( 'jetpack_lazy_images_skip_image_with_attributes', false, $attributes ) ) { - return $attributes; - } - - $old_attributes = $attributes; - - // Stash srcset and sizes in data attributes. - foreach ( array( 'srcset', 'sizes' ) as $attribute ) { - if ( isset( $old_attributes[ $attribute ] ) ) { - $attributes[ "data-lazy-$attribute" ] = $old_attributes[ $attribute ]; - unset( $attributes[ $attribute ] ); - } - } - - // We set this, adding the query arg so that it doesn't exactly equal the src attribute, so that photon JavaScript - // will hold off on processing this image. - $attributes['data-lazy-src'] = esc_url_raw( add_query_arg( 'is-pending-load', true, $attributes['src'] ) ); - - $attributes['srcset'] = self::get_placeholder_image(); - $attributes['class'] = sprintf( - '%s jetpack-lazy-image', - empty( $old_attributes['class'] ) - ? '' - : $old_attributes['class'] - ); - - /** - * Allow plugins and themes to override the attributes on the image before the content is updated. - * - * One potential use of this filter is for themes that set `height:auto` on the `img` tag. - * With this filter, the theme could get the width and height attributes from the - * $attributes array and then add a style tag that sets those values as well, which could - * minimize reflow as images load. - * - * @module lazy-images - * - * @since 5.6.0 - * - * @param array An array containing the attributes for the image, where the key is the attribute name - * and the value is the attribute value. - */ - return apply_filters( 'jetpack_lazy_images_new_attributes', $attributes ); - } - - /** - * Adds JavaScript to check if the current browser supports JavaScript as well as some styles to hide lazy - * images when the browser does not support JavaScript. - * - * @return void - */ - public function add_nojs_fallback() { - ?> - <style type="text/css"> - /* If html does not have either class, do not show lazy loaded images. */ - html:not( .jetpack-lazy-images-js-enabled ):not( .js ) .jetpack-lazy-image { - display: none; - } - </style> - <script> - document.documentElement.classList.add( - 'jetpack-lazy-images-js-enabled' - ); - </script> - <?php - } - - /** - * Retrieves the placeholder image after running it through the lazyload_images_placeholder_image filter. - * - * @return string The placeholder image source. - */ - private static function get_placeholder_image() { - /** - * Allows plugins and themes to modify the placeholder image. - * - * This filter is not prefixed with jetpack_ to provide a smoother migration - * process from the WordPress Lazy Load plugin. - * - * @module lazy-images - * - * @since 5.6.0 - * @since 6.5.0 Default image is now a base64 encoded transparent gif. - * - * @param string The URL to the placeholder image - */ - return apply_filters( - 'lazyload_images_placeholder_image', - 'data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7' - ); - } - - private static function flatten_kses_hair_data( $attributes ) { - $flattened_attributes = array(); - foreach ( $attributes as $name => $attribute ) { - $flattened_attributes[ $name ] = $attribute['value']; - } - return $flattened_attributes; - } - - private static function build_attributes_string( $attributes ) { - $string = array(); - foreach ( $attributes as $name => $value ) { - if ( '' === $value ) { - $string[] = sprintf( '%s', $name ); - } else { - $string[] = sprintf( '%s="%s"', $name, esc_attr( $value ) ); - } - } - return implode( ' ', $string ); - } - - public function enqueue_assets() { - wp_enqueue_script( - 'jetpack-lazy-images', - Jetpack::get_file_url_for_environment( - '_inc/build/lazy-images/js/lazy-images.min.js', - 'modules/lazy-images/js/lazy-images.js' - ), - array( 'jquery' ), - JETPACK__VERSION, - true - ); - } -} |