packages/kirki-framework/module-webfonts/src/Webfonts/Embed.php
<?php
/**
* Adds the Webfont Loader to load fonts asyncronously.
*
* @package kirki-framework/module-webfonts
* @author Ari Stathopoulos (@aristath)
* @copyright Copyright (c) 2019, Ari Stathopoulos (@aristath)
* @license https://opensource.org/licenses/MIT
* @since 1.0.0
*/
namespace Kirki\Module\Webfonts;
use Kirki\Module\Webfonts\Helper;
/**
* Manages the way Google Fonts are enqueued.
*/
final class Embed {
/**
* The config ID.
*
* @access protected
* @since 1.0.0
* @var string
*/
protected $config_id;
/**
* The \Kirki\Module\Webfonts object.
*
* @access protected
* @since 1.0.0
* @var object
*/
protected $webfonts;
/**
* The \Kirki\Module\Webfonts\Google object.
*
* @access protected
* @since 1.0.0
* @var object
*/
protected $googlefonts;
/**
* Fonts to load.
*
* @access protected
* @since 1.0.0
* @var array
*/
protected $fonts_to_load = [];
/**
* Constructor.
*
* @access public
* @since 1.0.0
* @param string $config_id The config-ID.
* @param object $webfonts The \Kirki\Module\Webfonts object.
* @param object $googlefonts The \Kirki\Module\Webfonts\Google object.
* @param array $args Extra args we want to pass.
*/
public function __construct( $config_id, $webfonts, $googlefonts, $args = [] ) {
$this->config_id = $config_id;
$this->webfonts = $webfonts;
$this->googlefonts = $googlefonts;
add_action( 'wp', [ $this, 'init' ], 9 );
add_filter( 'wp_resource_hints', [ $this, 'resource_hints' ], 10, 2 );
}
/**
* Init.
*
* @access public
* @since 1.0.0
* @return void
*/
public function init() {
$this->populate_fonts();
add_action( 'kirki_dynamic_css', [ $this, 'the_css' ] );
}
/**
* Add preconnect for Google Fonts.
*
* @access public
* @param array $urls URLs to print for resource hints.
* @param string $relation_type The relation type the URLs are printed.
* @return array $urls URLs to print for resource hints.
*/
public function resource_hints( $urls, $relation_type ) {
$fonts_to_load = $this->googlefonts->fonts;
if ( ! empty( $fonts_to_load ) && 'preconnect' === $relation_type ) {
$urls[] = [
'href' => 'https://fonts.gstatic.com',
'crossorigin',
];
}
return $urls;
}
/**
* Webfont Loader for Google Fonts.
*
* @access public
* @since 1.0.0
*/
public function populate_fonts() {
// Go through our fields and populate $this->fonts.
$this->webfonts->loop_fields( $this->config_id );
$this->googlefonts->fonts = apply_filters( 'kirki_enqueue_google_fonts', $this->googlefonts->fonts );
// Goes through $this->fonts and adds or removes things as needed.
$this->googlefonts->process_fonts();
foreach ( $this->googlefonts->fonts as $font => $weights ) {
foreach ( $weights as $key => $value ) {
if ( 'italic' === $value ) {
$weights[ $key ] = '400i';
} else {
$weights[ $key ] = str_replace( [ 'regular', 'bold', 'italic' ], [ '400', '', 'i' ], $value );
}
}
$this->fonts_to_load[] = [
'family' => $font,
'weights' => $weights,
];
}
}
/**
* Webfont Loader script for Google Fonts.
*
* @access public
* @since 1.0.0
*/
public function the_css() {
foreach ( $this->fonts_to_load as $font ) {
$family = str_replace( ' ', '+', trim( $font['family'] ) );
$weights = join( ',', $font['weights'] );
$url = "https://fonts.googleapis.com/css?family={$family}:{$weights}&subset=cyrillic,cyrillic-ext,devanagari,greek,greek-ext,khmer,latin,latin-ext,vietnamese,hebrew,arabic,bengali,gujarati,tamil,telugu,thai";
$transient_id = 'kirki_gfonts_' . md5( $url );
$contents = get_transient( $transient_id );
/**
* Reset the cache if we're using action=kirki-reset-cache in the URL.
*
* Note to code reviewers:
* There's no need to check nonces or anything else, this is a simple true/false evaluation.
*/
if ( ! empty( $_GET['action'] ) && 'kirki-reset-cache' === $_GET['action'] ) { // phpcs:ignore WordPress.Security.NonceVerification
$contents = false;
}
if ( ! $contents ) {
// Get the contents of the remote URL.
$contents = Helper::get_remote_url_contents(
$url,
[
'headers' => [
/**
* Set user-agent to firefox so that we get woff files.
* If we want woff2, use this instead: 'Mozilla/5.0 (X11; Linux i686; rv:64.0) Gecko/20100101 Firefox/64.0'
*/
'user-agent' => 'Mozilla/5.0 (X11; Linux i686; rv:21.0) Gecko/20100101 Firefox/21.0',
],
]
);
/**
* Allow filtering the font-display property.
*/
$font_display = apply_filters( 'kirki_googlefonts_font_display', 'swap' );
if ( $contents ) {
// Add font-display:swap to improve rendering speed.
$contents = str_replace( '@font-face {', '@font-face{', $contents );
$contents = str_replace( '@font-face{', '@font-face{font-display:' . $font_display . ';', $contents );
// Remove blank lines and extra spaces.
$contents = str_replace(
[ ': ', '; ', '; ', ' ' ],
[ ':', ';', ';', ' ' ],
preg_replace( "/\r|\n/", '', $contents )
);
// Use local fonts.
if ( apply_filters( 'kirki_use_local_fonts', true ) ) {
$contents = $this->use_local_files( $contents );
}
// Remove protocol to fix http/https issues.
$contents = str_replace(
[ 'http://', 'https://' ],
[ '//', '//' ],
$contents
);
// Set the transient for a day.
set_transient( $transient_id, $contents, DAY_IN_SECONDS );
}
}
if ( $contents ) {
/**
* Note to code reviewers:
*
* Though all output should be run through an escaping function, this is pure CSS
* and it is added on a call that has a PHP `header( 'Content-type: text/css' );`.
* No code, script or anything else can be executed from inside a stylesheet.
* For extra security we're using the wp_strip_all_tags() function here
* just to make sure there's no <script> tags in there or anything else.
*/
echo wp_strip_all_tags( $contents ); // phpcs:ignore WordPress.Security.EscapeOutput
}
}
}
/**
* Downloads font-files locally and uses the local files instead of the ones from Google's servers.
* This addresses any and all GDPR concerns, as well as firewalls that exist in some parts of the world.
*
* @access private
* @since 1.0.0
* @param string $css The CSS with original URLs.
* @return string The CSS with local URLs.
*/
private function use_local_files( $css ) {
preg_match_all( '/https\:.*?\.woff/', $css, $matches );
$matches = array_shift( $matches );
foreach ( $matches as $match ) {
if ( 0 === strpos( $match, 'https://fonts.gstatic.com' ) ) {
$new_url = Helper::download_font_file( $match );
if ( $new_url ) {
$css = str_replace( $match, $new_url, $css );
}
}
}
return $css;
}
}