Runs the theme.json webfonts handler.
Description
Using WP_Theme_JSON_Resolver
, it gets the fonts defined in the theme.json
for the current selection and style variations, validates the font-face properties, generates the ‘@font-face’ style declarations, and then enqueues the styles for both the editor and front-end.
Design Notes: This is not a public API, but rather an internal handler.
A future public Webfonts API will replace this stopgap code.
This code design is intentional.
a. It hides the inner-workings.
b. It does not expose API ins or outs for consumption.
c. It only works with a theme’s theme.json
.
Why? a. To avoid backwards-compatibility issues when the Webfonts API is introduced in Core.
b. To make fontFace
declarations in theme.json
work.
Source
function _wp_theme_json_webfonts_handler() {
_deprecated_function( __FUNCTION__, '6.4.0', 'wp_print_font_faces' );
// Block themes are unavailable during installation.
if ( wp_installing() ) {
return;
}
if ( ! wp_theme_has_theme_json() ) {
return;
}
// Webfonts to be processed.
$registered_webfonts = array();
/**
* Gets the webfonts from theme.json.
*
* @since 6.0.0
*
* @return array Array of defined webfonts.
*/
$fn_get_webfonts_from_theme_json = static function() {
// Get settings from theme.json.
$settings = WP_Theme_JSON_Resolver::get_merged_data()->get_settings();
// If in the editor, add webfonts defined in variations.
if ( is_admin() || wp_is_rest_endpoint() ) {
$variations = WP_Theme_JSON_Resolver::get_style_variations();
foreach ( $variations as $variation ) {
// Skip if fontFamilies are not defined in the variation.
if ( empty( $variation['settings']['typography']['fontFamilies'] ) ) {
continue;
}
// Initialize the array structure.
if ( empty( $settings['typography'] ) ) {
$settings['typography'] = array();
}
if ( empty( $settings['typography']['fontFamilies'] ) ) {
$settings['typography']['fontFamilies'] = array();
}
if ( empty( $settings['typography']['fontFamilies']['theme'] ) ) {
$settings['typography']['fontFamilies']['theme'] = array();
}
// Combine variations with settings. Remove duplicates.
$settings['typography']['fontFamilies']['theme'] = array_merge( $settings['typography']['fontFamilies']['theme'], $variation['settings']['typography']['fontFamilies']['theme'] );
$settings['typography']['fontFamilies'] = array_unique( $settings['typography']['fontFamilies'] );
}
}
// Bail out early if there are no settings for webfonts.
if ( empty( $settings['typography']['fontFamilies'] ) ) {
return array();
}
$webfonts = array();
// Look for fontFamilies.
foreach ( $settings['typography']['fontFamilies'] as $font_families ) {
foreach ( $font_families as $font_family ) {
// Skip if fontFace is not defined.
if ( empty( $font_family['fontFace'] ) ) {
continue;
}
// Skip if fontFace is not an array of webfonts.
if ( ! is_array( $font_family['fontFace'] ) ) {
continue;
}
$webfonts = array_merge( $webfonts, $font_family['fontFace'] );
}
}
return $webfonts;
};
/**
* Transforms each 'src' into an URI by replacing 'file:./'
* placeholder from theme.json.
*
* The absolute path to the webfont file(s) cannot be defined in
* theme.json. `file:./` is the placeholder which is replaced by
* the theme's URL path to the theme's root.
*
* @since 6.0.0
*
* @param array $src Webfont file(s) `src`.
* @return array Webfont's `src` in URI.
*/
$fn_transform_src_into_uri = static function( array $src ) {
foreach ( $src as $key => $url ) {
// Tweak the URL to be relative to the theme root.
if ( ! str_starts_with( $url, 'file:./' ) ) {
continue;
}
$src[ $key ] = get_theme_file_uri( str_replace( 'file:./', '', $url ) );
}
return $src;
};
/**
* Converts the font-face properties (i.e. keys) into kebab-case.
*
* @since 6.0.0
*
* @param array $font_face Font face to convert.
* @return array Font faces with each property in kebab-case format.
*/
$fn_convert_keys_to_kebab_case = static function( array $font_face ) {
foreach ( $font_face as $property => $value ) {
$kebab_case = _wp_to_kebab_case( $property );
$font_face[ $kebab_case ] = $value;
if ( $kebab_case !== $property ) {
unset( $font_face[ $property ] );
}
}
return $font_face;
};
/**
* Validates a webfont.
*
* @since 6.0.0
*
* @param array $webfont The webfont arguments.
* @return array|false The validated webfont arguments, or false if the webfont is invalid.
*/
$fn_validate_webfont = static function( $webfont ) {
$webfont = wp_parse_args(
$webfont,
array(
'font-family' => '',
'font-style' => 'normal',
'font-weight' => '400',
'font-display' => 'fallback',
'src' => array(),
)
);
// Check the font-family.
if ( empty( $webfont['font-family'] ) || ! is_string( $webfont['font-family'] ) ) {
trigger_error( __( 'Webfont font family must be a non-empty string.' ) );
return false;
}
// Check that the `src` property is defined and a valid type.
if ( empty( $webfont['src'] ) || ( ! is_string( $webfont['src'] ) && ! is_array( $webfont['src'] ) ) ) {
trigger_error( __( 'Webfont src must be a non-empty string or an array of strings.' ) );
return false;
}
// Validate the `src` property.
foreach ( (array) $webfont['src'] as $src ) {
if ( ! is_string( $src ) || '' === trim( $src ) ) {
trigger_error( __( 'Each webfont src must be a non-empty string.' ) );
return false;
}
}
// Check the font-weight.
if ( ! is_string( $webfont['font-weight'] ) && ! is_int( $webfont['font-weight'] ) ) {
trigger_error( __( 'Webfont font weight must be a properly formatted string or integer.' ) );
return false;
}
// Check the font-display.
if ( ! in_array( $webfont['font-display'], array( 'auto', 'block', 'fallback', 'optional', 'swap' ), true ) ) {
$webfont['font-display'] = 'fallback';
}
$valid_props = array(
'ascend-override',
'descend-override',
'font-display',
'font-family',
'font-stretch',
'font-style',
'font-weight',
'font-variant',
'font-feature-settings',
'font-variation-settings',
'line-gap-override',
'size-adjust',
'src',
'unicode-range',
);
foreach ( $webfont as $prop => $value ) {
if ( ! in_array( $prop, $valid_props, true ) ) {
unset( $webfont[ $prop ] );
}
}
return $webfont;
};
/**
* Registers webfonts declared in theme.json.
*
* @since 6.0.0
*
* @uses $registered_webfonts To access and update the registered webfonts registry (passed by reference).
* @uses $fn_get_webfonts_from_theme_json To run the function that gets the webfonts from theme.json.
* @uses $fn_convert_keys_to_kebab_case To run the function that converts keys into kebab-case.
* @uses $fn_validate_webfont To run the function that validates each font-face (webfont) from theme.json.
*/
$fn_register_webfonts = static function() use ( &$registered_webfonts, $fn_get_webfonts_from_theme_json, $fn_convert_keys_to_kebab_case, $fn_validate_webfont, $fn_transform_src_into_uri ) {
$registered_webfonts = array();
foreach ( $fn_get_webfonts_from_theme_json() as $webfont ) {
if ( ! is_array( $webfont ) ) {
continue;
}
$webfont = $fn_convert_keys_to_kebab_case( $webfont );
$webfont = $fn_validate_webfont( $webfont );
$webfont['src'] = $fn_transform_src_into_uri( (array) $webfont['src'] );
// Skip if not valid.
if ( empty( $webfont ) ) {
continue;
}
$registered_webfonts[] = $webfont;
}
};
/**
* Orders 'src' items to optimize for browser support.
*
* @since 6.0.0
*
* @param array $webfont Webfont to process.
* @return array Ordered `src` items.
*/
$fn_order_src = static function( array $webfont ) {
$src = array();
$src_ordered = array();
foreach ( $webfont['src'] as $url ) {
// Add data URIs first.
if ( str_starts_with( trim( $url ), 'data:' ) ) {
$src_ordered[] = array(
'url' => $url,
'format' => 'data',
);
continue;
}
$format = pathinfo( $url, PATHINFO_EXTENSION );
$src[ $format ] = $url;
}
// Add woff2.
if ( ! empty( $src['woff2'] ) ) {
$src_ordered[] = array(
'url' => sanitize_url( $src['woff2'] ),
'format' => 'woff2',
);
}
// Add woff.
if ( ! empty( $src['woff'] ) ) {
$src_ordered[] = array(
'url' => sanitize_url( $src['woff'] ),
'format' => 'woff',
);
}
// Add ttf.
if ( ! empty( $src['ttf'] ) ) {
$src_ordered[] = array(
'url' => sanitize_url( $src['ttf'] ),
'format' => 'truetype',
);
}
// Add eot.
if ( ! empty( $src['eot'] ) ) {
$src_ordered[] = array(
'url' => sanitize_url( $src['eot'] ),
'format' => 'embedded-opentype',
);
}
// Add otf.
if ( ! empty( $src['otf'] ) ) {
$src_ordered[] = array(
'url' => sanitize_url( $src['otf'] ),
'format' => 'opentype',
);
}
$webfont['src'] = $src_ordered;
return $webfont;
};
/**
* Compiles the 'src' into valid CSS.
*
* @since 6.0.0
* @since 6.2.0 Removed local() CSS.
*
* @param string $font_family Font family.
* @param array $value Value to process.
* @return string The CSS.
*/
$fn_compile_src = static function( $font_family, array $value ) {
$src = '';
foreach ( $value as $item ) {
$src .= ( 'data' === $item['format'] )
? ", url({$item['url']})"
: ", url('{$item['url']}') format('{$item['format']}')";
}
$src = ltrim( $src, ', ' );
return $src;
};
/**
* Compiles the font variation settings.
*
* @since 6.0.0
*
* @param array $font_variation_settings Array of font variation settings.
* @return string The CSS.
*/
$fn_compile_variations = static function( array $font_variation_settings ) {
$variations = '';
foreach ( $font_variation_settings as $key => $value ) {
$variations .= "$key $value";
}
return $variations;
};
/**
* Builds the font-family's CSS.
*
* @since 6.0.0
*
* @uses $fn_compile_src To run the function that compiles the src.
* @uses $fn_compile_variations To run the function that compiles the variations.
*
* @param array $webfont Webfont to process.
* @return string This font-family's CSS.
*/
$fn_build_font_face_css = static function( array $webfont ) use ( $fn_compile_src, $fn_compile_variations ) {
$css = '';
// Wrap font-family in quotes if it contains spaces.
if (
str_contains( $webfont['font-family'], ' ' ) &&
! str_contains( $webfont['font-family'], '"' ) &&
! str_contains( $webfont['font-family'], "'" )
) {
$webfont['font-family'] = '"' . $webfont['font-family'] . '"';
}
foreach ( $webfont as $key => $value ) {
/*
* Skip "provider", since it's for internal API use,
* and not a valid CSS property.
*/
if ( 'provider' === $key ) {
continue;
}
// Compile the "src" parameter.
if ( 'src' === $key ) {
$value = $fn_compile_src( $webfont['font-family'], $value );
}
// If font-variation-settings is an array, convert it to a string.
if ( 'font-variation-settings' === $key && is_array( $value ) ) {
$value = $fn_compile_variations( $value );
}
if ( ! empty( $value ) ) {
$css .= "$key:$value;";
}
}
return $css;
};
/**
* Gets the '@font-face' CSS styles for locally-hosted font files.
*
* @since 6.0.0
*
* @uses $registered_webfonts To access and update the registered webfonts registry (passed by reference).
* @uses $fn_order_src To run the function that orders the src.
* @uses $fn_build_font_face_css To run the function that builds the font-face CSS.
*
* @return string The `@font-face` CSS.
*/
$fn_get_css = static function() use ( &$registered_webfonts, $fn_order_src, $fn_build_font_face_css ) {
$css = '';
foreach ( $registered_webfonts as $webfont ) {
// Order the webfont's `src` items to optimize for browser support.
$webfont = $fn_order_src( $webfont );
// Build the @font-face CSS for this webfont.
$css .= '@font-face{' . $fn_build_font_face_css( $webfont ) . '}';
}
return $css;
};
/**
* Generates and enqueues webfonts styles.
*
* @since 6.0.0
*
* @uses $fn_get_css To run the function that gets the CSS.
*/
$fn_generate_and_enqueue_styles = static function() use ( $fn_get_css ) {
// Generate the styles.
$styles = $fn_get_css();
// Bail out if there are no styles to enqueue.
if ( '' === $styles ) {
return;
}
// Enqueue the stylesheet.
wp_register_style( 'wp-webfonts', '' );
wp_enqueue_style( 'wp-webfonts' );
// Add the styles to the stylesheet.
wp_add_inline_style( 'wp-webfonts', $styles );
};
/**
* Generates and enqueues editor styles.
*
* @since 6.0.0
*
* @uses $fn_get_css To run the function that gets the CSS.
*/
$fn_generate_and_enqueue_editor_styles = static function() use ( $fn_get_css ) {
// Generate the styles.
$styles = $fn_get_css();
// Bail out if there are no styles to enqueue.
if ( '' === $styles ) {
return;
}
wp_add_inline_style( 'wp-block-library', $styles );
};
add_action( 'wp_loaded', $fn_register_webfonts );
add_action( 'wp_enqueue_scripts', $fn_generate_and_enqueue_styles );
add_action( 'admin_init', $fn_generate_and_enqueue_editor_styles );
}
Changelog
Version | Description |
---|---|
6.4.0 | Use wp_print_font_faces() instead. |
6.0.0 | Introduced. |
User Contributed Notes
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