Jetpack_Lazy_Images - Code Metrics - Inspection of "reset wordpress after connection tests" - Automattic/jetpack - Measure and Improve Code Quality continuously with Scrutinizer

Completed

Push — add/e2e-connection-purchase-fl... ( d02cce...68beb5 )

by Yaroslav

created 2020-09-16 10:59 UTC

Jetpack_Lazy_Images B

↳ Parent: Project

Complexity

Total Complexity

Size/Duplication

Total Lines	462
Duplicated Lines	3.46 %

Coupling/Cohesion

Components	2
Dependencies	1

Importance

Changes

Metric	Value
dl	16
loc	462
rs	8.96
c	0
b	0
f	0
wmc	43
lcom	2
cbo	1

15 Methods

Rating	Name	Duplication	Size	Complexity
A	instance()	0	7	2
A	is_amp_request()	0	12	2
A	__construct()	0	34	4
A	setup_filters()	8	8	1
A	remove_filters()	8	8	1
A	allow_lazy_attributes()	0	19	2
A	add_image_placeholders()	0	16	4
B	should_skip_image_with_blocked_class()	0	41	5
A	process_image()	0	20	4
C	process_image_attributes()	0	82	10
A	add_nojs_fallback()	0	15	1
A	get_placeholder_image()	0	19	1
A	flatten_kses_hair_data()	0	7	2
A	build_attributes_string()	0	11	3
A	enqueue_assets()	0	9	1

How to fix Duplicated Code Complexity

Duplicated Code

Duplicate code is one of the most pungent code smells. A rule that is often used is to re-structure code once it is duplicated in three or more places.

Common duplication problems, and corresponding solutions are:

If you have the same expression in different places: Extract expression to a method
If you have the same method in different sub-classes: Extract method, and pull up field to the parent class
If you have the same code in unrelated classes: Consider extracting the code to a new class, and injecting that class

Complex Class

Tip: Before tackling complexity, make sure that you eliminate any duplication first. This often can reduce the size of classes significantly.

Complex classes like Jetpack_Lazy_Images often do a lot of different things. To break such a class down, we need to identify a cohesive component within that class. A common approach to find such a component is to look for fields/methods that share the same prefixes, or suffixes. You can also have a look at the cohesion graph to spot any un-connected, or weakly-connected components.

Once you have determined the fields that belong together, you can apply the Extract Class refactoring. If the component makes sense as a sub-class, Extract Subclass is also a candidate, and is often faster.

While breaking up the class, it is a good idea to analyze how other classes use Jetpack_Lazy_Images, and based on these observations, apply Extract Interface, too.

<?php // phpcs:ignore WordPress.Files.FileName.InvalidClassFileName

/**
 * The Lazy Images package.
 *
 * @since 8.8
 *
 * This package has been lifted from the Jetpack modules folder and adapted to be
 * an standalone package reusable outside Jetpack.
 *
 * @package automattic/jetpack-lazy-images
 */

/**
 * This package relies heavily upon the Lazy Load plugin which was worked on by
 * Mohammad Jangda (batmoo), the WordPress.com VIP team, the TechCrunch 2011
 * redesign team, and Jake Goldman of 10up LLC.
 *
 * The JavaScript has been updated to rely on InterSection observer instead of
 * jQuery Sonar. Many thanks to Dean Hume (deanhume) and his example:
 * https://github.com/deanhume/lazy-observer-load
 */

namespace Automattic\Jetpack;

use Automattic\Jetpack\Assets;
use Automattic\Jetpack\Constants as Jetpack_Constants;

/**
 * Class Automattic\Jetpack\Jetpack_Lazy_Images
 *
 * @since 8.8
 */
class Jetpack_Lazy_Images {

	/**
	 * The assets version.
	 *
	 * @since 8.8
	 *
	 * @var string Assets version.
	 */
	const ASSETS_VERSION = '1.0.0';

	/**
	 * Class instance.
	 *
	 * @since 5.6.0
	 *
	 * @var null
	 */
	private static $instance = null;

	/**
	 * Singleton implementation.
	 *
	 * @since 5.6.0
	 *
	 * @return object The class instance.
	 */
	public static function instance() {
		if ( is_null( self::$instance ) ) {
			self::$instance = new Jetpack_Lazy_Images();

		}

		return self::$instance;
	}

	/**
	 * Check if the request is a AMP request.
	 *
	 * @since 8.8
	 *
	 * @return bool
	 */
	public static function is_amp_request() {
		$is_amp_request = ( function_exists( 'is_amp_endpoint' ) && is_amp_endpoint() );

		/**
		 * Returns true if the current request should return valid AMP content.
		 *
		 * @since 8.8
		 *
		 * @param boolean $is_amp_request Is this request supposed to return valid AMP content?
		 */
		return apply_filters( 'jetpack_lazy_images_is_amp_request', $is_amp_request );
	}

	/**
	 * Registers actions.
	 *
	 * @since 8.8
	 *
	 * @return void

	 */
	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.
		 *
		 * @package automattic/jetpack-lazy-images
		 *
		 * @since 5.6.0
		 *
		 * @param bool true Whether lazy image loading should occur.
		 */
		if ( ! apply_filters( 'lazyload_is_enabled', true ) ) {
			return;
		}

		if ( self::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' ) );
	}

	/**
	 * Setup filters.
	 *
	 * @since 5.6.0
	 *
	 * @return void
	 */
	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 );
	}

	/**
	 * Remove filters.
	 *
	 * @since 5.6.0
	 *
	 * @return void
	 */
	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.
	 *
	 * @since 5.6.0
	 *
	 * @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;
	}

	/**
	 * Add image placeholders.
	 *
	 * @since 5.6.0
	 *
	 * @param string $content Content.
	 * @return string
	 */
	public function add_image_placeholders( $content ) {
		// Don't lazy load 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_blocked_class( $classes ) {
		$blocked_classes = array(
			'skip-lazy',
			'gazette-featured-content-thumbnail',
		);

		/**
		 * Allow plugins and themes to tell lazy images to skip an image with a given class.
		 *
		 * @package automattic/jetpack-lazy-images
		 *
		 * @since 5.9.0
		 * @deprecated 8.7.0 Use jetpack_lazy_images_blocked_classes
		 *
		 * @param array An array of strings where each string is a class.
		 */
		$blocked_classes = apply_filters_deprecated( 'jetpack_lazy_images_blacklisted_classes', array( $blocked_classes ), 'Jetpack 8.7.0', 'jetpack_lazy_images_blocked_classes' );

		/**
		 * Allow plugins and themes to tell lazy images to skip an image with a given class.
		 *
		 * @package automattic/jetpack-lazy-images
		 *
		 * @since 8.7.0
		 *
		 * @param array An array of strings where each string is a class.
		 */
		$blocked_classes = apply_filters( 'jetpack_lazy_images_blocked_classes', $blocked_classes );

		if ( ! is_array( $blocked_classes ) || empty( $blocked_classes ) ) {
			return false;
		}

		foreach ( $blocked_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 Matches.
	 *
	 * @return string The image with updated lazy attributes.
	 */
	public 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 Attributes.
	 *
	 * @return array The updated image attributes array with lazy load attributes.
	 */
	public static function process_image_attributes( $attributes ) {
		if ( empty( $attributes['src'] ) ) {
			return $attributes;
		}

		if ( ! empty( $attributes['class'] ) && self::should_skip_image_with_blocked_class( $attributes['class'] ) ) {
			return $attributes;
		}

		if ( isset( $attributes['data-skip-lazy'] ) ) {
			return $attributes;
		}

		/**
		 * Allow plugins and themes to conditionally skip processing an image via its attributes.
		 *
		 * @package automattic/jetpack-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.
		 *
		 * @package automattic/jetpack-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.
		 *
		 * @package automattic/jetpack-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.
	 *
	 * @since 5.6.0
	 *
	 * @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.
	 *
	 * @since 5.6.0
	 *
	 * @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'
		);
	}

	/**
	 * Flatter KSES hair data.
	 *
	 * @since 5.6.0
	 *
	 * @param array $attributes Attributes.
	 *
	 * @return array
	 */
	private static function flatten_kses_hair_data( $attributes ) {
		$flattened_attributes = array();
		foreach ( $attributes as $name => $attribute ) {
			$flattened_attributes[ $name ] = $attribute['value'];
		}
		return $flattened_attributes;
	}

	/**
	 * Build attributes string.
	 *
	 * @since 5.6.0
	 *
	 * @param array $attributes Attributes.
	 *
	 * @return string
	 */
	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 );
	}

	/**
	 * Enqueue assets.
	 *
	 * @since 5.6.0
	 *
	 * @return void
	 */
	public function enqueue_assets() {
		wp_enqueue_script(
			'jetpack-lazy-images',
			Assets::get_file_url_for_environment( 'js/lazy-images.min.js', 'js/lazy-images.js', __FILE__ ),
			array(),
			self::ASSETS_VERSION,
			true
		);
	}
}


1		<?php // phpcs:ignore WordPress.Files.FileName.InvalidClassFileName
2
3		/**
4		* The Lazy Images package.
5		*
6		* @since 8.8
7		*
8		* This package has been lifted from the Jetpack modules folder and adapted to be
9		* an standalone package reusable outside Jetpack.
10		*
11		* @package automattic/jetpack-lazy-images
12		*/
13
14		/**
15		* This package relies heavily upon the Lazy Load plugin which was worked on by
16		* Mohammad Jangda (batmoo), the WordPress.com VIP team, the TechCrunch 2011
17		* redesign team, and Jake Goldman of 10up LLC.
18		*
19		* The JavaScript has been updated to rely on InterSection observer instead of
20		* jQuery Sonar. Many thanks to Dean Hume (deanhume) and his example:
21		* https://github.com/deanhume/lazy-observer-load
22		*/
23
24		namespace Automattic\Jetpack;
25
26		use Automattic\Jetpack\Assets;
27		use Automattic\Jetpack\Constants as Jetpack_Constants;
28
29		/**
30		* Class Automattic\Jetpack\Jetpack_Lazy_Images
31		*
32		* @since 8.8
33		*/
34		class Jetpack_Lazy_Images {
35
36		/**
37		* The assets version.
38		*
39		* @since 8.8
40		*
41		* @var string Assets version.
42		*/
43		const ASSETS_VERSION = '1.0.0';
44
45		/**
46		* Class instance.
47		*
48		* @since 5.6.0
49		*
50		* @var null
51		*/
52		private static $instance = null;
53
54		/**
55		* Singleton implementation.
56		*
57		* @since 5.6.0
58		*
59		* @return object The class instance.
60		*/
61		public static function instance() {
62		if ( is_null( self::$instance ) ) {
63		self::$instance = new Jetpack_Lazy_Images();
		0 ignored issues – show Documentation Bug introduced 2020-07-31 06:26 UTC by Report Bug Copy Issue Report It seems like `new \Automattic\Jetpack\Jetpack_Lazy_Images()` of type `object<Automattic\Jetpack\Jetpack_Lazy_Images>` is incompatible with the declared type `null` of property `$instance`. Our type inference engine has found an assignment to a property that is incompatible with the declared type of that property. Either this assignment is in error or the assigned type should be added to the documentation/type hint for that property.. Loading history...
64		}
65
66		return self::$instance;
67		}
68
69		/**
70		* Check if the request is a AMP request.
71		*
72		* @since 8.8
73		*
74		* @return bool
75		*/
76		public static function is_amp_request() {
77		$is_amp_request = ( function_exists( 'is_amp_endpoint' ) && is_amp_endpoint() );
78
79		/**
80		* Returns true if the current request should return valid AMP content.
81		*
82		* @since 8.8
83		*
84		* @param boolean $is_amp_request Is this request supposed to return valid AMP content?
85		*/
86		return apply_filters( 'jetpack_lazy_images_is_amp_request', $is_amp_request );
87		}
88
89		/**
90		* Registers actions.
91		*
92		* @since 8.8
93		*
94		* @return void
		0 ignored issues – show Comprehensibility Best Practice introduced 2020-07-31 06:26 UTC by Report Bug Copy Issue Report Adding a `@return` annotation to constructors is generally not recommended as a constructor does not have a meaningful return value. Adding a `@return` annotation to a constructor is not recommended, since a constructor does not have a meaningful return value. Please refer to the PHP core documentation on constructors. Loading history...
95		*/
96		private function __construct() {
97		if ( is_admin() ) {
98		return;
99		}
100
101		/**
102		* Whether the lazy-images module should load.
103		*
104		* This filter is not prefixed with jetpack_ to provide a smoother migration
105		* process from the WordPress Lazy Load plugin.
106		*
107		* @package automattic/jetpack-lazy-images
108		*
109		* @since 5.6.0
110		*
111		* @param bool true Whether lazy image loading should occur.
112		*/
113		if ( ! apply_filters( 'lazyload_is_enabled', true ) ) {
114		return;
115		}
116
117		if ( self::is_amp_request() ) {
118		return;
119		}
120
121		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.
122		add_action( 'wp_enqueue_scripts', array( $this, 'enqueue_assets' ) );
123
124		// Do not lazy load avatar in admin bar.
125		add_action( 'admin_bar_menu', array( $this, 'remove_filters' ), 0 );
126
127		add_filter( 'wp_kses_allowed_html', array( $this, 'allow_lazy_attributes' ) );
128		add_action( 'wp_head', array( $this, 'add_nojs_fallback' ) );
129		}
130
131		/**
132		* Setup filters.
133		*
134		* @since 5.6.0
135		*
136		* @return void
137		*/
138	View Code Duplication	public function setup_filters() {
139		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.
140		add_filter( 'post_thumbnail_html', array( $this, 'add_image_placeholders' ), PHP_INT_MAX );
141		add_filter( 'get_avatar', array( $this, 'add_image_placeholders' ), PHP_INT_MAX );
142		add_filter( 'widget_text', array( $this, 'add_image_placeholders' ), PHP_INT_MAX );
143		add_filter( 'get_image_tag', array( $this, 'add_image_placeholders' ), PHP_INT_MAX );
144		add_filter( 'wp_get_attachment_image_attributes', array( __CLASS__, 'process_image_attributes' ), PHP_INT_MAX );
145		}
146
147		/**
148		* Remove filters.
149		*
150		* @since 5.6.0
151		*
152		* @return void
153		*/
154	View Code Duplication	public function remove_filters() {
155		remove_filter( 'the_content', array( $this, 'add_image_placeholders' ), PHP_INT_MAX );
156		remove_filter( 'post_thumbnail_html', array( $this, 'add_image_placeholders' ), PHP_INT_MAX );
157		remove_filter( 'get_avatar', array( $this, 'add_image_placeholders' ), PHP_INT_MAX );
158		remove_filter( 'widget_text', array( $this, 'add_image_placeholders' ), PHP_INT_MAX );
159		remove_filter( 'get_image_tag', array( $this, 'add_image_placeholders' ), PHP_INT_MAX );
160		remove_filter( 'wp_get_attachment_image_attributes', array( __CLASS__, 'process_image_attributes' ), PHP_INT_MAX );
161		}
162
163		/**
164		* Ensure that our lazy image attributes are not filtered out of image tags.
165		*
166		* @since 5.6.0
167		*
168		* @param array $allowed_tags The allowed tags and their attributes.
169		* @return array
170		*/
171		public function allow_lazy_attributes( $allowed_tags ) {
172		if ( ! isset( $allowed_tags['img'] ) ) {
173		return $allowed_tags;
174		}
175
176		// But, if images are allowed, ensure that our attributes are allowed!
177		$img_attributes = array_merge(
178		$allowed_tags['img'],
179		array(
180		'data-lazy-src' => 1,
181		'data-lazy-srcset' => 1,
182		'data-lazy-sizes' => 1,
183		)
184		);
185
186		$allowed_tags['img'] = $img_attributes;
187
188		return $allowed_tags;
189		}
190
191		/**
192		* Add image placeholders.
193		*
194		* @since 5.6.0
195		*
196		* @param string $content Content.
197		* @return string
198		*/
199		public function add_image_placeholders( $content ) {
200		// Don't lazy load for feeds, previews.
201		if ( is_feed() \|\| is_preview() ) {
202		return $content;
203		}
204
205		// Don't lazy-load if the content has already been run through previously.
206		if ( false !== strpos( $content, 'data-lazy-src' ) ) {
207		return $content;
208		}
209
210		// This is a pretty simple regex, but it works.
211		$content = preg_replace_callback( '#<(img)([^>]+?)(>(.*?)</\\1>\|[\/]?>)#si', array( __CLASS__, 'process_image' ), $content );
212
213		return $content;
214		}
215
216		/**
217		* Returns true when a given string of classes contains a class signifying lazy images.
218		* should not process the image.
219		*
220		* @since 5.9.0
221		*
222		* @param string $classes A string of space-separated classes.
223		* @return bool
224		*/
225		public static function should_skip_image_with_blocked_class( $classes ) {
226		$blocked_classes = array(
227		'skip-lazy',
228		'gazette-featured-content-thumbnail',
229		);
230
231		/**
232		* Allow plugins and themes to tell lazy images to skip an image with a given class.
233		*
234		* @package automattic/jetpack-lazy-images
235		*
236		* @since 5.9.0
237		* @deprecated 8.7.0 Use jetpack_lazy_images_blocked_classes
238		*
239		* @param array An array of strings where each string is a class.
240		*/
241		$blocked_classes = apply_filters_deprecated( 'jetpack_lazy_images_blacklisted_classes', array( $blocked_classes ), 'Jetpack 8.7.0', 'jetpack_lazy_images_blocked_classes' );
242
243		/**
244		* Allow plugins and themes to tell lazy images to skip an image with a given class.
245		*
246		* @package automattic/jetpack-lazy-images
247		*
248		* @since 8.7.0
249		*
250		* @param array An array of strings where each string is a class.
251		*/
252		$blocked_classes = apply_filters( 'jetpack_lazy_images_blocked_classes', $blocked_classes );
253
254		if ( ! is_array( $blocked_classes ) \|\| empty( $blocked_classes ) ) {
255		return false;
256		}
257
258		foreach ( $blocked_classes as $class ) {
259		if ( false !== strpos( $classes, $class ) ) {
260		return true;
261		}
262		}
263
264		return false;
265		}
266
267		/**
268		* Processes images in content by acting as the preg_replace_callback.
269		*
270		* @since 5.6.0
271		*
272		* @param array $matches Matches.
273		*
274		* @return string The image with updated lazy attributes.
275		*/
276		public static function process_image( $matches ) {
277		$old_attributes_str = $matches[2];
278		$old_attributes_kses_hair = wp_kses_hair( $old_attributes_str, wp_allowed_protocols() );
279
280		if ( empty( $old_attributes_kses_hair['src'] ) ) {
281		return $matches[0];
282		}
283
284		$old_attributes = self::flatten_kses_hair_data( $old_attributes_kses_hair );
285
286		// If we didn't add lazy attributes, just return the original image source.
287		if ( ! empty( $old_attributes['class'] ) && false !== strpos( $old_attributes['class'], 'jetpack-lazy-image' ) ) {
288		return $matches[0];
289		}
290
291		$new_attributes = self::process_image_attributes( $old_attributes );
292		$new_attributes_str = self::build_attributes_string( $new_attributes );
293
294		return sprintf( '<img %1$s><noscript>%2$s</noscript>', $new_attributes_str, $matches[0] );
295		}
296
297		/**
298		* Given an array of image attributes, updates the `src`, `srcset`, and `sizes` attributes so
299		* that they load lazily.
300		*
301		* @since 5.7.0
302		*
303		* @param array $attributes Attributes.
304		*
305		* @return array The updated image attributes array with lazy load attributes.
306		*/
307		public static function process_image_attributes( $attributes ) {
308		if ( empty( $attributes['src'] ) ) {
309		return $attributes;
310		}
311
312		if ( ! empty( $attributes['class'] ) && self::should_skip_image_with_blocked_class( $attributes['class'] ) ) {
313		return $attributes;
314		}
315
316		if ( isset( $attributes['data-skip-lazy'] ) ) {
317		return $attributes;
318		}
319
320		/**
321		* Allow plugins and themes to conditionally skip processing an image via its attributes.
322		*
323		* @package automattic/jetpack-lazy-images
324		*
325		* @deprecated 6.5.0 Use jetpack_lazy_images_skip_image_with_attributes instead.
326		* @since 5.9.0
327		*
328		* @param bool Default to not skip processing the current image.
329		* @param array An array of attributes via wp_kses_hair() for the current image.
330		*/
331		if ( apply_filters( 'jetpack_lazy_images_skip_image_with_atttributes', false, $attributes ) ) {
		0 ignored issues – show Unused Code introduced 2020-05-15 22:01 UTC by Report Bug Copy Issue Report The call to `apply_filters()` has too many arguments starting with `$attributes`. This check compares calls to functions or methods with their respective definitions. If the call has more arguments than are defined, it raises an issue. If a function is defined several times with a different number of parameters, the check may pick up the wrong definition and report false positives. One codebase where this has been known to happen is Wordpress. In this case you can add the `@ignore` PhpDoc annotation to the duplicate definition and it will be ignored. Loading history...
332		return $attributes;
333		}
334
335		/**
336		* Allow plugins and themes to conditionally skip processing an image via its attributes.
337		*
338		* @package automattic/jetpack-lazy-images
339		*
340		* @since 6.5.0 Filter name was updated from jetpack_lazy_images_skip_image_with_atttributes to correct typo.
341		* @since 5.9.0
342		*
343		* @param bool Default to not skip processing the current image.
344		* @param array An array of attributes via wp_kses_hair() for the current image.
345		*/
346		if ( apply_filters( 'jetpack_lazy_images_skip_image_with_attributes', false, $attributes ) ) {
		0 ignored issues – show Unused Code introduced 2020-05-15 22:01 UTC by Report Bug Copy Issue Report The call to `apply_filters()` has too many arguments starting with `$attributes`. This check compares calls to functions or methods with their respective definitions. If the call has more arguments than are defined, it raises an issue. If a function is defined several times with a different number of parameters, the check may pick up the wrong definition and report false positives. One codebase where this has been known to happen is Wordpress. In this case you can add the `@ignore` PhpDoc annotation to the duplicate definition and it will be ignored. Loading history...
347		return $attributes;
348		}
349
350		$old_attributes = $attributes;
351
352		// Stash srcset and sizes in data attributes.
353		foreach ( array( 'srcset', 'sizes' ) as $attribute ) {
354		if ( isset( $old_attributes[ $attribute ] ) ) {
355		$attributes[ "data-lazy-$attribute" ] = $old_attributes[ $attribute ];
356		unset( $attributes[ $attribute ] );
357		}
358		}
359
360		// We set this, adding the query arg so that it doesn't exactly equal the src attribute, so that photon JavaScript
361		// will hold off on processing this image.
362		$attributes['data-lazy-src'] = esc_url_raw( add_query_arg( 'is-pending-load', true, $attributes['src'] ) );
363
364		$attributes['srcset'] = self::get_placeholder_image();
365		$attributes['class'] = sprintf(
366		'%s jetpack-lazy-image',
367		empty( $old_attributes['class'] )
368		? ''
369		: $old_attributes['class']
370		);
371
372		/**
373		* Allow plugins and themes to override the attributes on the image before the content is updated.
374		*
375		* One potential use of this filter is for themes that set `height:auto` on the `img` tag.
376		* With this filter, the theme could get the width and height attributes from the
377		* $attributes array and then add a style tag that sets those values as well, which could
378		* minimize reflow as images load.
379		*
380		* @package automattic/jetpack-lazy-images
381		*
382		* @since 5.6.0
383		*
384		* @param array An array containing the attributes for the image, where the key is the attribute name
385		* and the value is the attribute value.
386		*/
387		return apply_filters( 'jetpack_lazy_images_new_attributes', $attributes );
388		}
389
390		/**
391		* Adds JavaScript to check if the current browser supports JavaScript as well as some styles to hide lazy
392		* images when the browser does not support JavaScript.
393		*
394		* @since 5.6.0
395		*
396		* @return void
397		*/
398		public function add_nojs_fallback() {
399		?>
400		<style type="text/css">
401		/* If html does not have either class, do not show lazy loaded images. */
402		html:not( .jetpack-lazy-images-js-enabled ):not( .js ) .jetpack-lazy-image {
403		display: none;
404		}
405		</style>
406		<script>
407		document.documentElement.classList.add(
408		'jetpack-lazy-images-js-enabled'
409		);
410		</script>
411		<?php
412		}
413
414		/**
415		* Retrieves the placeholder image after running it through the lazyload_images_placeholder_image filter.
416		*
417		* @since 5.6.0
418		*
419		* @return string The placeholder image source.
420		*/
421		private static function get_placeholder_image() {
422		/**
423		* Allows plugins and themes to modify the placeholder image.
424		*
425		* This filter is not prefixed with jetpack_ to provide a smoother migration
426		* process from the WordPress Lazy Load plugin.
427		*
428		* @module lazy-images
429		*
430		* @since 5.6.0
431		* @since 6.5.0 Default image is now a base64 encoded transparent gif.
432		*
433		* @param string The URL to the placeholder image.
434		*/
435		return apply_filters(
436		'lazyload_images_placeholder_image',
437		'data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7'
438		);
439		}
440
441		/**
442		* Flatter KSES hair data.
443		*
444		* @since 5.6.0
445		*
446		* @param array $attributes Attributes.
447		*
448		* @return array
449		*/
450		private static function flatten_kses_hair_data( $attributes ) {
451		$flattened_attributes = array();
452		foreach ( $attributes as $name => $attribute ) {
453		$flattened_attributes[ $name ] = $attribute['value'];
454		}
455		return $flattened_attributes;
456		}
457
458		/**
459		* Build attributes string.
460		*
461		* @since 5.6.0
462		*
463		* @param array $attributes Attributes.
464		*
465		* @return string
466		*/
467		private static function build_attributes_string( $attributes ) {
468		$string = array();
469		foreach ( $attributes as $name => $value ) {
470		if ( '' === $value ) {
471		$string[] = sprintf( '%s', $name );
472		} else {
473		$string[] = sprintf( '%s="%s"', $name, esc_attr( $value ) );
474		}
475		}
476		return implode( ' ', $string );
477		}
478
479		/**
480		* Enqueue assets.
481		*
482		* @since 5.6.0
483		*
484		* @return void
485		*/
486		public function enqueue_assets() {
487		wp_enqueue_script(
488		'jetpack-lazy-images',
489		Assets::get_file_url_for_environment( 'js/lazy-images.min.js', 'js/lazy-images.js', __FILE__ ),
490		array(),
491		self::ASSETS_VERSION,
492		true
493		);
494		}
495		}
496

Automattic / jetpack