Jetpack_Perf_Optimize_Assets - Code Metrics - Inspection of "Move style links to bottom of header; fix for defe..." - Automattic/jetpack - Measure and Improve Code Quality continuously with Scrutinizer

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Push — add/pwa ( 80f574...bade54 )

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created 2017-11-01 18:38 UTC

Jetpack_Perf_Optimize_Assets D

↳ Parent: Project

Complexity

Total Complexity

Size/Duplication

Total Lines	405
Duplicated Lines	22.72 %

Coupling/Cohesion

Components	2
Dependencies	0

Importance

Changes

Metric	Value
dl	92
loc	405
rs	4.8717
c	0
b	0
f	0
wmc	83
lcom	2
cbo	0

27 Methods

Rating	Name	Duplication	Size	Complexity
A	instance()	0	7	2
A	disable_for_request()	0	6	1
C	__construct()	0	48	8
A	disable_emojis()	0	15	1
A	optimize_jetpack()	0	3	1
A	disable_emojis_tinymce()	0	7	2
A	disable_emojis_remove_dns_prefetch()	0	10	2
A	set_first_load_cookie()	3	5	2
A	send_scripts_to_footer()	11	17	3
A	move_styles_to_bottom_of_header()	0	4	1
A	set_asset_groups()	0	8	2
A	remove_external_font_scripts()	0	4	1
A	remove_external_font_styles()	0	4	1
A	filter_inline_scripts()	16	16	4
D	print_inline_scripts()	0	33	9
B	should_async_script()	19	19	6
B	should_defer_script()	18	18	6
A	should_remove_script()	0	3	1
A	should_inline_script()	0	3	3
A	filter_inline_styles()	15	15	4
B	print_inline_styles()	0	20	5
A	should_inline_style()	0	3	3
A	should_remove_style()	0	3	1
D	should_inline_asset()	0	29	9
A	should_remove_asset()	0	3	1
A	register_inline_script()	5	11	2
A	register_inline_style()	5	9	2

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_Perf_Optimize_Assets 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_Perf_Optimize_Assets, and based on these observations, apply Extract Interface, too.

<?php

/**
 * Optimizes page assets for unreliable networks and fast rendering, particularly with empty caches
 * - inline scripts and styles
 * - async external JS
 * - remove references to external fonts
 * - move CSS links below scripts in head (scripts after CSS blocks render until script finishes downloading)
 */

class Jetpack_Perf_Optimize_Assets {
	private static $__instance = null;
	private $remove_remote_fonts = false;
	private $inline_scripts_and_styles = false;
	private $async_scripts = false;
	private $defer_scripts = false;

	/**
	 * Singleton implementation
	 *
	 * @return object
	 */
	public static function instance() {
		if ( ! is_a( self::$__instance, 'Jetpack_Perf_Optimize_Assets' ) ) {
			self::$__instance = new Jetpack_Perf_Optimize_Assets();
		}

		return self::$__instance;
	}

	public function disable_for_request() {
		$this->remove_remote_fonts = false;
		$this->inline_scripts_and_styles = false;
		$this->async_scripts = false;
		$this->defer_scripts = false;
	}

	/**
	 * TODO: detect if this is worth doing for wp-admin?

	 */

	/**
	 * Registers actions
	 */
	private function __construct() {
		$this->is_first_load             = ! isset( $_COOKIE['jetpack_perf_loaded'] );
class MyClass { }

$x = new MyClass();
$x->foo = true;
		$this->remove_remote_fonts       = get_option( 'perf_remove_remote_fonts', true );
		$this->inline_always             = get_option( 'perf_inline_on_every_request', false );
class MyClass { }

$x = new MyClass();
$x->foo = true;
		$this->inline_scripts_and_styles = get_option( 'perf_inline_scripts_and_styles', true ) && ( $this->is_first_load || $this->inline_always );
		$this->async_scripts             = get_option( 'perf_async_scripts', true );
		$this->defer_scripts             = get_option( 'perf_defer_scripts', true );
		$this->move_scripts_to_footer    = true;
class MyClass { }

$x = new MyClass();
$x->foo = true;
		$this->move_scripts_above_css_in_header = true;
class MyClass { }

$x = new MyClass();
$x->foo = true;
		$this->remove_core_emojis        = true;
class MyClass { }

$x = new MyClass();
$x->foo = true;

		if ( $this->remove_remote_fonts ) {
			add_filter( 'jetpack_perf_remove_script', array( $this, 'remove_external_font_scripts' ), 10, 3 );
			add_filter( 'jetpack_perf_remove_style', array( $this, 'remove_external_font_styles' ), 10, 3 );
		}

		if ( $this->move_scripts_to_footer ) {
			add_filter( 'jetpack_perf_asset_group', array( $this, 'set_asset_groups' ), 10, 2 );
		}

		if ( $this->move_scripts_above_css_in_header ) {
			add_action( 'init', array( $this, 'move_styles_to_bottom_of_header' ), PHP_INT_MAX );
		}

		if ( $this->inline_scripts_and_styles ) {
			add_filter( 'jetpack_implode_frontend_css', '__return_false' );
		}

		add_action( 'wp_enqueue_scripts', array( $this, 'send_scripts_to_footer' ), PHP_INT_MAX );
		add_filter( 'script_loader_src', array( $this, 'filter_inline_scripts' ), -100, 2 );
		add_filter( 'script_loader_tag', array( $this, 'print_inline_scripts' ), -100, 3 );
		add_filter( 'style_loader_src', array( $this, 'filter_inline_styles' ), -100, 2 );
		add_filter( 'style_loader_tag', array( $this, 'print_inline_styles' ), -100, 4 );

		add_action( 'init', array( $this, 'set_first_load_cookie' ) );

		/**
		 * Feature, theme and plugin-specific hacks
		 */

		// remove emoji detection - TODO a setting for this

		if ( $this->remove_core_emojis ) {
			add_action( 'init', array( $this, 'disable_emojis' ) );
		}

		// inline/defer/async stuff for Jetpack
		add_action( 'init', array( $this, 'optimize_jetpack' ) );
	}

	/** Disabling Emojis **/
	// improves page load performance

	function disable_emojis() {
		remove_action( 'wp_head', 'print_emoji_detection_script', 7 );
		remove_action( 'admin_print_scripts', 'print_emoji_detection_script' );
		remove_action( 'embed_head', 'print_emoji_detection_script', 7 );

		remove_action( 'wp_print_styles', 'print_emoji_styles' );
		remove_action( 'admin_print_styles', 'print_emoji_styles' );

		remove_filter( 'the_content_feed', 'wp_staticize_emoji' );
		remove_filter( 'comment_text_rss', 'wp_staticize_emoji' );
		remove_filter( 'wp_mail', 'wp_staticize_emoji_for_email' );

		add_filter( 'tiny_mce_plugins', array( $this, 'disable_emojis_tinymce' ) );
		add_filter( 'wp_resource_hints', array( $this, 'disable_emojis_remove_dns_prefetch' ), 10, 2 );
	}

	function optimize_jetpack() {

	}

	/**
	 * Filter function used to remove the tinymce emoji plugin.
	 *
	 * @param array $plugins
	 * @return array Difference betwen the two arrays
	 */
	function disable_emojis_tinymce( $plugins ) {
		if ( is_array( $plugins ) ) {
			return array_diff( $plugins, array( 'wpemoji' ) );
		} else {
			return array();
		}
	}

	/**
	 * Remove emoji CDN hostname from DNS prefetching hints.
	 *
	 * @param array $urls URLs to print for resource hints.
	 * @param string $relation_type The relation type the URLs are printed for.
	 * @return array Difference betwen the two arrays.
	 */
	function disable_emojis_remove_dns_prefetch( $urls, $relation_type ) {
		if ( 'dns-prefetch' == $relation_type ) {
			/** This filter is documented in wp-includes/formatting.php */
			$emoji_svg_url = apply_filters( 'emoji_svg_url', 'https://s.w.org/images/core/emoji/2/svg/' );

			$urls = array_diff( $urls, array( $emoji_svg_url ) );
		}

		return $urls;
	}

	// by default we only inline scripts+styles on first page load for a given user
	function set_first_load_cookie() {
		if ( ! isset( $_COOKIE['jetpack_perf_loaded'] ) ) {
			setcookie( 'jetpack_perf_loaded', '1', time() + YEAR_IN_SECONDS, COOKIEPATH, COOKIE_DOMAIN );
		}
	}

	// this code essentially sets the default asset location to the footer rather than the head
	function send_scripts_to_footer() {
		global $wp_scripts;

		// fetch all deps for head
		$wp_scripts->all_deps( $wp_scripts->queue, true, 1 );
		foreach( $wp_scripts->to_do as $handle ) {
			$registration = $wp_scripts->registered[$handle];
			if ( $registration->args !== NULL ) {
				// skip, this asset has an explicit location
				continue;
			}

			$asset_group = apply_filters( 'jetpack_perf_asset_group', 1, $handle );
			$registration->args = $asset_group;
			$wp_scripts->groups[$handle] = $asset_group;
		}
	}

	// scripts that run after CSS <link>s in the header block waiting for the CSS to load
	// so we move styles as late as possible in the wp_head action to maximise the chance
	// of non-blocking rendering
	function move_styles_to_bottom_of_header() {
		remove_action( 'wp_head', 'wp_print_styles', 8 );
		add_action( 'wp_head', 'wp_print_styles', 999 );
	}

	function set_asset_groups( $group, $handle ) {
		// force jquery into header, everything else can go in footer unless filtered elsewhere
		if ( in_array( $handle, array( 'jquery-core', 'jquery-migrate', 'jquery' ) ) ) {
			return 0;
		}

		return $group;
	}

	/** FILTERS **/
	public function remove_external_font_scripts( $should_remove, $handle, $asset_url ) {
		$font_script_url = 'http://use.typekit.com/';
		return strncmp( $asset_url, $font_script_url, strlen( $font_script_url ) ) === 0;
	}

	public function remove_external_font_styles( $should_remove, $handle, $asset_url ) {
		$font_url = 'https://fonts.googleapis.com';
		return strncmp( $asset_url, $font_url, strlen( $font_url ) ) === 0;
	}

	/** SCRIPTS **/
	public function filter_inline_scripts( $src, $handle ) {
		global $wp_scripts;

		if ( is_admin() || ! isset( $wp_scripts->registered[$handle] ) ) {
			return $src;
		}

		$script = $wp_scripts->registered[$handle];

		// reset src to empty - can't return empty string though because then it skips rendering the tag
		if ( $this->should_inline_script( $script ) ) {
			return '#';
		}

		return $src;
	}

	public function print_inline_scripts( $tag, $handle, $src ) {
		global $wp_scripts;

		if ( is_admin() || ! isset( $wp_scripts->registered[$handle] ) ) {
			return $tag;
		}

		$script = $wp_scripts->registered[$handle];

		if ( $this->should_remove_script( $script ) ) {
			return '';
		}

		if ( $this->should_inline_script( $script ) ) {
			$label = '<!-- ' . $script->src . '-->';
			// base64-encoding a script into the src URL only makes sense if we intend to async or defer it
			if ( $this->should_defer_script( $script ) ) {
				$tag = $label . '<script defer type="text/javascript" src="data:text/javascript;base64,' . base64_encode( file_get_contents( $script->extra['jetpack-inline-file'] ) ) . '"></script>';
			} elseif ( $this->should_async_script( $script ) ) {
				$tag = $label . '<script async type="text/javascript" src="data:text/javascript;base64,' . base64_encode( file_get_contents( $script->extra['jetpack-inline-file'] ) ) . '"></script>';
			} else {
				$tag = $label . '<script type="text/javascript">' . file_get_contents( $script->extra['jetpack-inline-file'] ) . '</script>';
			}
		} else {
			if ( $this->should_defer_script( $script ) ) {
				$tag = preg_replace( '/<script /', '<script defer ', $tag );
			} elseif ( $this->should_async_script( $script ) ) {
				$tag = preg_replace( '/<script /', '<script async ', $tag );
			}
		}

		return $tag;
	}

	private function should_async_script( $script ) {
		global $wp_scripts;

		// explicitly in the header (scripts aren't affected much by async)
		$should_async_script = $script->args === 0;

		// only make scripts async if nothing depends on them
		foreach ( $wp_scripts->to_do as $other_script_handle ) {
			$other_script = $wp_scripts->registered[ $other_script_handle ];
			if ( in_array( $script->handle, $other_script->deps ) ) {
				$should_async_script = false;
				break;
			}
		}

		// you can override this logic by setting jetpack-async
		$should_async_script = $should_async_script || ( isset( $script->extra['jetpack-async'] ) && $script->extra['jetpack-async'] );
		return $this->async_scripts && apply_filters( 'jetpack_perf_async_script', $should_async_script, $script->handle, $script->src );
	}

	private function should_defer_script( $script ) {
		global $wp_scripts;

		// if it's explicitly not in the footer, or we have Jetpack Defer set, and has no dependencies
		$should_defer_script = $script->args === 0;

		// only make scripts deferred if nothing depends on them
		foreach ( $wp_scripts->to_do as $other_script_handle ) {
			$other_script = $wp_scripts->registered[ $other_script_handle ];
			if ( in_array( $script->handle, $other_script->deps ) ) {
				$should_defer_script = false;
				break;
			}
		}

		$should_defer_script = $should_defer_script || ( isset( $script->extra['jetpack-defer'] ) && $script->extra['jetpack-defer'] );
		return $this->defer_scripts && apply_filters( 'jetpack_perf_defer_script', $should_defer_script, $script->handle, $script->src );
	}

	private function should_remove_script( $script ) {
		return $this->should_remove_asset( 'jetpack_perf_remove_script', $script );
	}

	private function should_inline_script( $script ) {
		return ( $this->inline_scripts_and_styles || $this->inline_always ) && $this->should_inline_asset( 'jetpack_perf_inline_script', $script );
	}

	/** STYLES **/
	public function filter_inline_styles( $src, $handle ) {
		global $wp_scripts;

		if ( is_admin() || ! isset( $wp_scripts->registered[$handle] ) ) {
			return $src;
		}

		$style = $wp_scripts->registered[$handle];

		if ( $this->should_inline_style( $style ) ) {
			return '#';
		}

		return $src;
	}

	public function print_inline_styles( $tag, $handle, $href, $media ) {
		global $wp_styles;

		if ( is_admin() || ! isset( $wp_styles->registered[$handle] ) ) {
			return $tag;
		}

		$style = $wp_styles->registered[$handle];

		if ( $this->should_inline_style( $style ) ) {
			$label = '<!-- ' . $style->src . '-->';
			return "$label<style type='text/css' media='$media'>" . file_get_contents( $style->extra['jetpack-inline-file'] ) . '</style>';
		}

		if ( $this->should_remove_style( $style ) ) {
			return '';
		}

		return $tag;
	}

	private function should_inline_style( $style ) {
		return ( $this->inline_scripts_and_styles || $this->inline_always ) && $this->should_inline_asset( 'jetpack_perf_inline_style', $style );
	}

	private function should_remove_style( $style ) {
		return $this->should_remove_asset( 'jetpack_perf_remove_style', $style );
	}

	/** shared code **/

	private function should_inline_asset( $filter, $dependency ) {
		// inline anything local, with a src starting with /, or starting with site_url
		$site_url = site_url();

		$is_local_url = ( strncmp( $dependency->src, '/', 1 ) === 0 && strncmp( $dependency->src, '//', 2 ) !== 0 )
			|| strpos( $dependency->src, $site_url ) === 0;

		if ( $is_local_url && ! isset( $dependency->extra['jetpack-inline'] ) ) {
			$dependency->extra['jetpack-inline'] = true;

			$path = untrailingslashit( ABSPATH ) . str_replace( $site_url, '', $dependency->src );

			if ( ! file_exists( $path ) ) {
				$path = str_replace('/', DIRECTORY_SEPARATOR, str_replace( $site_url, '', $dependency->src ));

				$prefix = explode( DIRECTORY_SEPARATOR, untrailingslashit( WP_CONTENT_DIR ) );
				$prefix = array_slice( $prefix, 0, array_search( $path[1], $prefix ) - 1 );

				$path = implode( DIRECTORY_SEPARATOR, $prefix ) . $path;
			}

			$dependency->extra['jetpack-inline-file'] = $path;
		}

		// only inline if we don't have a conditional
		$should_inline = ! isset( $dependency->extra['conditional'] ) && isset( $dependency->extra['jetpack-inline'] ) && $dependency->extra['jetpack-inline'];

		return apply_filters( $filter, $should_inline, $dependency->handle, $dependency->src ) && file_exists( $dependency->extra['jetpack-inline-file'] );
	}

	private function should_remove_asset( $filter, $dependency ) {
		return apply_filters( $filter, false, $dependency->handle, $dependency->src );
	}

	/**
	 * if inline assets are enabled, renders inline
	 * TODO: enable this just for certain paths/patterns/filetypes

	 * This is actually currently unused
	 */
	 public function register_inline_script( $handle, $file, $plugin_file, $deps = false, $ver = false, $in_footer = false ) {
		$registered = wp_register_script( $handle, plugins_url( $file, $plugin_file ), $deps, $ver, $in_footer );

		if ( $registered ) {
			$file_full_path = dirname( $plugin_file ) . '/' . $file;
			wp_script_add_data( $handle, 'jetpack-inline', true );
			wp_script_add_data( $handle, 'jetpack-inline-file', $file_full_path );
		}

		return $registered;
	}

	/**
	 * if inline assets are enabled, renders inline
	 * TODO: enable this just for certain paths/patterns/filetypes

	 * This is actually currently unused
	 */
	public function register_inline_style( $handle, $file, $plugin_file, $deps = array(), $ver = false, $media = 'all' ) {
		$registered = wp_register_style( $handle, plugins_url( $file, $plugin_file ), $deps, $ver, $media );

		if ( $registered ) {
			$file_full_path = dirname( $plugin_file ) . '/' . $file;
			wp_style_add_data( $handle, 'jetpack-inline', true );
			wp_style_add_data( $handle, 'jetpack-inline-file', $file_full_path );
		}
	}
}


1		<?php
2
3		/**
4		* Optimizes page assets for unreliable networks and fast rendering, particularly with empty caches
5		* - inline scripts and styles
6		* - async external JS
7		* - remove references to external fonts
8		* - move CSS links below scripts in head (scripts after CSS blocks render until script finishes downloading)
9		*/
10
11		class Jetpack_Perf_Optimize_Assets {
12		private static $__instance = null;
13		private $remove_remote_fonts = false;
14		private $inline_scripts_and_styles = false;
15		private $async_scripts = false;
16		private $defer_scripts = false;
17
18		/**
19		* Singleton implementation
20		*
21		* @return object
22		*/
23		public static function instance() {
24		if ( ! is_a( self::$__instance, 'Jetpack_Perf_Optimize_Assets' ) ) {
25		self::$__instance = new Jetpack_Perf_Optimize_Assets();
26		}
27
28		return self::$__instance;
29		}
30
31		public function disable_for_request() {
32		$this->remove_remote_fonts = false;
33		$this->inline_scripts_and_styles = false;
34		$this->async_scripts = false;
35		$this->defer_scripts = false;
36		}
37
38		/**
39		* TODO: detect if this is worth doing for wp-admin?
		0 ignored issues – show Coding Style Best Practice introduced 2017-10-18 04:25 UTC by Report Bug Copy Issue Report Comments for TODO tasks are often forgotten in the code; it might be better to use a dedicated issue tracker. Loading history...
40		*/
41
42		/**
43		* Registers actions
44		*/
45		private function __construct() {
46		$this->is_first_load = ! isset( $_COOKIE['jetpack_perf_loaded'] );
		0 ignored issues – show Bug introduced 2017-10-17 23:18 UTC by Report Bug Copy Issue Report The property `is_first_load` does not exist. Did you maybe forget to declare it? In PHP it is possible to write to properties without declaring them. For example, the following is perfectly valid PHP code: class MyClass { } $x = new MyClass(); $x->foo = true; Generally, it is a good practice to explictly declare properties to avoid accidental typos and provide IDE auto-completion: class MyClass { public $foo; } $x = new MyClass(); $x->foo = true; Loading history...
47		$this->remove_remote_fonts = get_option( 'perf_remove_remote_fonts', true );
48		$this->inline_always = get_option( 'perf_inline_on_every_request', false );
		0 ignored issues – show Bug introduced 2017-10-17 03:07 UTC by Report Bug Copy Issue Report The property `inline_always` does not exist. Did you maybe forget to declare it? In PHP it is possible to write to properties without declaring them. For example, the following is perfectly valid PHP code: class MyClass { } $x = new MyClass(); $x->foo = true; Generally, it is a good practice to explictly declare properties to avoid accidental typos and provide IDE auto-completion: class MyClass { public $foo; } $x = new MyClass(); $x->foo = true; Loading history...
49		$this->inline_scripts_and_styles = get_option( 'perf_inline_scripts_and_styles', true ) && ( $this->is_first_load \|\| $this->inline_always );
50		$this->async_scripts = get_option( 'perf_async_scripts', true );
51		$this->defer_scripts = get_option( 'perf_defer_scripts', true );
52		$this->move_scripts_to_footer = true;
		0 ignored issues – show Bug introduced 2017-10-31 18:23 UTC by Report Bug Copy Issue Report The property `move_scripts_to_footer` does not exist. Did you maybe forget to declare it? In PHP it is possible to write to properties without declaring them. For example, the following is perfectly valid PHP code: class MyClass { } $x = new MyClass(); $x->foo = true; Generally, it is a good practice to explictly declare properties to avoid accidental typos and provide IDE auto-completion: class MyClass { public $foo; } $x = new MyClass(); $x->foo = true; Loading history...
53		$this->move_scripts_above_css_in_header = true;
		0 ignored issues – show Bug introduced 2017-11-01 18:53 UTC by Report Bug Copy Issue Report The property `move_scripts_above_css_in_header` does not exist. Did you maybe forget to declare it? In PHP it is possible to write to properties without declaring them. For example, the following is perfectly valid PHP code: class MyClass { } $x = new MyClass(); $x->foo = true; Generally, it is a good practice to explictly declare properties to avoid accidental typos and provide IDE auto-completion: class MyClass { public $foo; } $x = new MyClass(); $x->foo = true; Loading history...
54		$this->remove_core_emojis = true;
		0 ignored issues – show Bug introduced 2017-11-01 18:53 UTC by Report Bug Copy Issue Report The property `remove_core_emojis` does not exist. Did you maybe forget to declare it? In PHP it is possible to write to properties without declaring them. For example, the following is perfectly valid PHP code: class MyClass { } $x = new MyClass(); $x->foo = true; Generally, it is a good practice to explictly declare properties to avoid accidental typos and provide IDE auto-completion: class MyClass { public $foo; } $x = new MyClass(); $x->foo = true; Loading history...
55
56		if ( $this->remove_remote_fonts ) {
57		add_filter( 'jetpack_perf_remove_script', array( $this, 'remove_external_font_scripts' ), 10, 3 );
58		add_filter( 'jetpack_perf_remove_style', array( $this, 'remove_external_font_styles' ), 10, 3 );
59		}
60
61		if ( $this->move_scripts_to_footer ) {
62		add_filter( 'jetpack_perf_asset_group', array( $this, 'set_asset_groups' ), 10, 2 );
63		}
64
65		if ( $this->move_scripts_above_css_in_header ) {
66		add_action( 'init', array( $this, 'move_styles_to_bottom_of_header' ), PHP_INT_MAX );
67		}
68
69		if ( $this->inline_scripts_and_styles ) {
70		add_filter( 'jetpack_implode_frontend_css', '__return_false' );
71		}
72
73		add_action( 'wp_enqueue_scripts', array( $this, 'send_scripts_to_footer' ), PHP_INT_MAX );
74		add_filter( 'script_loader_src', array( $this, 'filter_inline_scripts' ), -100, 2 );
75		add_filter( 'script_loader_tag', array( $this, 'print_inline_scripts' ), -100, 3 );
76		add_filter( 'style_loader_src', array( $this, 'filter_inline_styles' ), -100, 2 );
77		add_filter( 'style_loader_tag', array( $this, 'print_inline_styles' ), -100, 4 );
78
79		add_action( 'init', array( $this, 'set_first_load_cookie' ) );
80
81		/**
82		* Feature, theme and plugin-specific hacks
83		*/
84
85		// remove emoji detection - TODO a setting for this
		0 ignored issues – show Coding Style Best Practice introduced 2017-10-19 06:13 UTC by Report Bug Copy Issue Report Comments for TODO tasks are often forgotten in the code; it might be better to use a dedicated issue tracker. Loading history...
86		if ( $this->remove_core_emojis ) {
87		add_action( 'init', array( $this, 'disable_emojis' ) );
88		}
89
90		// inline/defer/async stuff for Jetpack
91		add_action( 'init', array( $this, 'optimize_jetpack' ) );
92		}
93
94		/ Disabling Emojis /
95		// improves page load performance
96
97		function disable_emojis() {
98		remove_action( 'wp_head', 'print_emoji_detection_script', 7 );
99		remove_action( 'admin_print_scripts', 'print_emoji_detection_script' );
100		remove_action( 'embed_head', 'print_emoji_detection_script', 7 );
101
102		remove_action( 'wp_print_styles', 'print_emoji_styles' );
103		remove_action( 'admin_print_styles', 'print_emoji_styles' );
104
105		remove_filter( 'the_content_feed', 'wp_staticize_emoji' );
106		remove_filter( 'comment_text_rss', 'wp_staticize_emoji' );
107		remove_filter( 'wp_mail', 'wp_staticize_emoji_for_email' );
108
109		add_filter( 'tiny_mce_plugins', array( $this, 'disable_emojis_tinymce' ) );
110		add_filter( 'wp_resource_hints', array( $this, 'disable_emojis_remove_dns_prefetch' ), 10, 2 );
111		}
112
113		function optimize_jetpack() {
114
115		}
116
117		/**
118		* Filter function used to remove the tinymce emoji plugin.
119		*
120		* @param array $plugins
121		* @return array Difference betwen the two arrays
122		*/
123		function disable_emojis_tinymce( $plugins ) {
124		if ( is_array( $plugins ) ) {
125		return array_diff( $plugins, array( 'wpemoji' ) );
126		} else {
127		return array();
128		}
129		}
130
131		/**
132		* Remove emoji CDN hostname from DNS prefetching hints.
133		*
134		* @param array $urls URLs to print for resource hints.
135		* @param string $relation_type The relation type the URLs are printed for.
136		* @return array Difference betwen the two arrays.
137		*/
138		function disable_emojis_remove_dns_prefetch( $urls, $relation_type ) {
139		if ( 'dns-prefetch' == $relation_type ) {
140		/** This filter is documented in wp-includes/formatting.php */
141		$emoji_svg_url = apply_filters( 'emoji_svg_url', 'https://s.w.org/images/core/emoji/2/svg/' );
142
143		$urls = array_diff( $urls, array( $emoji_svg_url ) );
144		}
145
146		return $urls;
147		}
148
149		// by default we only inline scripts+styles on first page load for a given user
150		function set_first_load_cookie() {
151	View Code Duplication	if ( ! isset( $_COOKIE['jetpack_perf_loaded'] ) ) {
152		setcookie( 'jetpack_perf_loaded', '1', time() + YEAR_IN_SECONDS, COOKIEPATH, COOKIE_DOMAIN );
153		}
154		}
155
156		// this code essentially sets the default asset location to the footer rather than the head
157		function send_scripts_to_footer() {
158		global $wp_scripts;
159
160		// fetch all deps for head
161		$wp_scripts->all_deps( $wp_scripts->queue, true, 1 );
162	View Code Duplication	foreach( $wp_scripts->to_do as $handle ) {
163		$registration = $wp_scripts->registered[$handle];
164		if ( $registration->args !== NULL ) {
165		// skip, this asset has an explicit location
166		continue;
167		}
168
169		$asset_group = apply_filters( 'jetpack_perf_asset_group', 1, $handle );
170		$registration->args = $asset_group;
171		$wp_scripts->groups[$handle] = $asset_group;
172		}
173		}
174
175		// scripts that run after CSS <link>s in the header block waiting for the CSS to load
176		// so we move styles as late as possible in the wp_head action to maximise the chance
177		// of non-blocking rendering
178		function move_styles_to_bottom_of_header() {
179		remove_action( 'wp_head', 'wp_print_styles', 8 );
180		add_action( 'wp_head', 'wp_print_styles', 999 );
181		}
182
183		function set_asset_groups( $group, $handle ) {
184		// force jquery into header, everything else can go in footer unless filtered elsewhere
185		if ( in_array( $handle, array( 'jquery-core', 'jquery-migrate', 'jquery' ) ) ) {
186		return 0;
187		}
188
189		return $group;
190		}
191
192		/ FILTERS /
193		public function remove_external_font_scripts( $should_remove, $handle, $asset_url ) {
194		$font_script_url = 'http://use.typekit.com/';
195		return strncmp( $asset_url, $font_script_url, strlen( $font_script_url ) ) === 0;
196		}
197
198		public function remove_external_font_styles( $should_remove, $handle, $asset_url ) {
199		$font_url = 'https://fonts.googleapis.com';
200		return strncmp( $asset_url, $font_url, strlen( $font_url ) ) === 0;
201		}
202
203		/ SCRIPTS /
204	View Code Duplication	public function filter_inline_scripts( $src, $handle ) {
205		global $wp_scripts;
206
207		if ( is_admin() \|\| ! isset( $wp_scripts->registered[$handle] ) ) {
208		return $src;
209		}
210
211		$script = $wp_scripts->registered[$handle];
212
213		// reset src to empty - can't return empty string though because then it skips rendering the tag
214		if ( $this->should_inline_script( $script ) ) {
215		return '#';
216		}
217
218		return $src;
219		}
220
221		public function print_inline_scripts( $tag, $handle, $src ) {
222		global $wp_scripts;
223
224		if ( is_admin() \|\| ! isset( $wp_scripts->registered[$handle] ) ) {
225		return $tag;
226		}
227
228		$script = $wp_scripts->registered[$handle];
229
230		if ( $this->should_remove_script( $script ) ) {
231		return '';
232		}
233
234		if ( $this->should_inline_script( $script ) ) {
235		$label = '<!-- ' . $script->src . '-->';
236		// base64-encoding a script into the src URL only makes sense if we intend to async or defer it
237		if ( $this->should_defer_script( $script ) ) {
238		$tag = $label . '<script defer type="text/javascript" src="data:text/javascript;base64,' . base64_encode( file_get_contents( $script->extra['jetpack-inline-file'] ) ) . '"></script>';
239		} elseif ( $this->should_async_script( $script ) ) {
240		$tag = $label . '<script async type="text/javascript" src="data:text/javascript;base64,' . base64_encode( file_get_contents( $script->extra['jetpack-inline-file'] ) ) . '"></script>';
241		} else {
242		$tag = $label . '<script type="text/javascript">' . file_get_contents( $script->extra['jetpack-inline-file'] ) . '</script>';
243		}
244		} else {
245		if ( $this->should_defer_script( $script ) ) {
246		$tag = preg_replace( '/<script /', '<script defer ', $tag );
247		} elseif ( $this->should_async_script( $script ) ) {
248		$tag = preg_replace( '/<script /', '<script async ', $tag );
249		}
250		}
251
252		return $tag;
253		}
254
255	View Code Duplication	private function should_async_script( $script ) {
256		global $wp_scripts;
257
258		// explicitly in the header (scripts aren't affected much by async)
259		$should_async_script = $script->args === 0;
260
261		// only make scripts async if nothing depends on them
262		foreach ( $wp_scripts->to_do as $other_script_handle ) {
263		$other_script = $wp_scripts->registered[ $other_script_handle ];
264		if ( in_array( $script->handle, $other_script->deps ) ) {
265		$should_async_script = false;
266		break;
267		}
268		}
269
270		// you can override this logic by setting jetpack-async
271		$should_async_script = $should_async_script \|\| ( isset( $script->extra['jetpack-async'] ) && $script->extra['jetpack-async'] );
272		return $this->async_scripts && apply_filters( 'jetpack_perf_async_script', $should_async_script, $script->handle, $script->src );
273		}
274
275	View Code Duplication	private function should_defer_script( $script ) {
276		global $wp_scripts;
277
278		// if it's explicitly not in the footer, or we have Jetpack Defer set, and has no dependencies
279		$should_defer_script = $script->args === 0;
280
281		// only make scripts deferred if nothing depends on them
282		foreach ( $wp_scripts->to_do as $other_script_handle ) {
283		$other_script = $wp_scripts->registered[ $other_script_handle ];
284		if ( in_array( $script->handle, $other_script->deps ) ) {
285		$should_defer_script = false;
286		break;
287		}
288		}
289
290		$should_defer_script = $should_defer_script \|\| ( isset( $script->extra['jetpack-defer'] ) && $script->extra['jetpack-defer'] );
291		return $this->defer_scripts && apply_filters( 'jetpack_perf_defer_script', $should_defer_script, $script->handle, $script->src );
292		}
293
294		private function should_remove_script( $script ) {
295		return $this->should_remove_asset( 'jetpack_perf_remove_script', $script );
296		}
297
298		private function should_inline_script( $script ) {
299		return ( $this->inline_scripts_and_styles \|\| $this->inline_always ) && $this->should_inline_asset( 'jetpack_perf_inline_script', $script );
300		}
301
302		/ STYLES /
303	View Code Duplication	public function filter_inline_styles( $src, $handle ) {
304		global $wp_scripts;
305
306		if ( is_admin() \|\| ! isset( $wp_scripts->registered[$handle] ) ) {
307		return $src;
308		}
309
310		$style = $wp_scripts->registered[$handle];
311
312		if ( $this->should_inline_style( $style ) ) {
313		return '#';
314		}
315
316		return $src;
317		}
318
319		public function print_inline_styles( $tag, $handle, $href, $media ) {
320		global $wp_styles;
321
322		if ( is_admin() \|\| ! isset( $wp_styles->registered[$handle] ) ) {
323		return $tag;
324		}
325
326		$style = $wp_styles->registered[$handle];
327
328		if ( $this->should_inline_style( $style ) ) {
329		$label = '<!-- ' . $style->src . '-->';
330		return "$label<style type='text/css' media='$media'>" . file_get_contents( $style->extra['jetpack-inline-file'] ) . '</style>';
331		}
332
333		if ( $this->should_remove_style( $style ) ) {
334		return '';
335		}
336
337		return $tag;
338		}
339
340		private function should_inline_style( $style ) {
341		return ( $this->inline_scripts_and_styles \|\| $this->inline_always ) && $this->should_inline_asset( 'jetpack_perf_inline_style', $style );
342		}
343
344		private function should_remove_style( $style ) {
345		return $this->should_remove_asset( 'jetpack_perf_remove_style', $style );
346		}
347
348		/ shared code /
349
350		private function should_inline_asset( $filter, $dependency ) {
351		// inline anything local, with a src starting with /, or starting with site_url
352		$site_url = site_url();
353
354		$is_local_url = ( strncmp( $dependency->src, '/', 1 ) === 0 && strncmp( $dependency->src, '//', 2 ) !== 0 )
355		\|\| strpos( $dependency->src, $site_url ) === 0;
356
357		if ( $is_local_url && ! isset( $dependency->extra['jetpack-inline'] ) ) {
358		$dependency->extra['jetpack-inline'] = true;
359
360		$path = untrailingslashit( ABSPATH ) . str_replace( $site_url, '', $dependency->src );
361
362		if ( ! file_exists( $path ) ) {
363		$path = str_replace('/', DIRECTORY_SEPARATOR, str_replace( $site_url, '', $dependency->src ));
364
365		$prefix = explode( DIRECTORY_SEPARATOR, untrailingslashit( WP_CONTENT_DIR ) );
366		$prefix = array_slice( $prefix, 0, array_search( $path[1], $prefix ) - 1 );
367
368		$path = implode( DIRECTORY_SEPARATOR, $prefix ) . $path;
369		}
370
371		$dependency->extra['jetpack-inline-file'] = $path;
372		}
373
374		// only inline if we don't have a conditional
375		$should_inline = ! isset( $dependency->extra['conditional'] ) && isset( $dependency->extra['jetpack-inline'] ) && $dependency->extra['jetpack-inline'];
376
377		return apply_filters( $filter, $should_inline, $dependency->handle, $dependency->src ) && file_exists( $dependency->extra['jetpack-inline-file'] );
378		}
379
380		private function should_remove_asset( $filter, $dependency ) {
381		return apply_filters( $filter, false, $dependency->handle, $dependency->src );
382		}
383
384		/**
385		* if inline assets are enabled, renders inline
386		* TODO: enable this just for certain paths/patterns/filetypes
		0 ignored issues – show Coding Style Best Practice introduced 2017-10-14 21:02 UTC by Report Bug Copy Issue Report Comments for TODO tasks are often forgotten in the code; it might be better to use a dedicated issue tracker. Loading history...
387		* This is actually currently unused
388		*/
389		public function register_inline_script( $handle, $file, $plugin_file, $deps = false, $ver = false, $in_footer = false ) {
390		$registered = wp_register_script( $handle, plugins_url( $file, $plugin_file ), $deps, $ver, $in_footer );
391
392	View Code Duplication	if ( $registered ) {
393		$file_full_path = dirname( $plugin_file ) . '/' . $file;
394		wp_script_add_data( $handle, 'jetpack-inline', true );
395		wp_script_add_data( $handle, 'jetpack-inline-file', $file_full_path );
396		}
397
398		return $registered;
399		}
400
401		/**
402		* if inline assets are enabled, renders inline
403		* TODO: enable this just for certain paths/patterns/filetypes
		0 ignored issues – show Coding Style Best Practice introduced 2017-10-13 00:14 UTC by Report Bug Copy Issue Report Comments for TODO tasks are often forgotten in the code; it might be better to use a dedicated issue tracker. Loading history...
404		* This is actually currently unused
405		*/
406		public function register_inline_style( $handle, $file, $plugin_file, $deps = array(), $ver = false, $media = 'all' ) {
407		$registered = wp_register_style( $handle, plugins_url( $file, $plugin_file ), $deps, $ver, $media );
408
409	View Code Duplication	if ( $registered ) {
410		$file_full_path = dirname( $plugin_file ) . '/' . $file;
411		wp_style_add_data( $handle, 'jetpack-inline', true );
412		wp_style_add_data( $handle, 'jetpack-inline-file', $file_full_path );
413		}
414		}
415		}
416

Automattic / jetpack