Singleton registry for font collections.

Since: 6.5.0
Source: wp-includes/fonts/class-wp-font-library.php

Description

The Font Library manages the registration and retrieval of font collections. It follows the singleton pattern to ensure a single global registry.

Properties

$collections

private array $collections = [];

Registered font collections, keyed by slug.

$instance

private static ?WP_Font_Library $instance = null;

Singleton instance.

Methods

get_instance()

Retrieves the main instance of the class.

public static function get_instance(): WP_Font_Library

Returns: The singleton instance.

Example:

$library = WP_Font_Library::get_instance();
$collections = $library->get_font_collections();

register_font_collection()

Registers a new font collection.

public function register_font_collection( string $slug, array $args ): WP_Font_Collection|WP_Error

Parameters:

Returns:

• WP_Font_Collection on success
• WP_Error if slug already registered

Example:

$library = WP_Font_Library::get_instance();
$collection = $library->register_font_collection( 'my-fonts', [
    'name'          => 'My Fonts',
    'font_families' => [...],
]);

unregister_font_collection()

Unregisters a font collection.

public function unregister_font_collection( string $slug ): bool

Parameters:

Returns: true if unregistered, false if not found.

Example:

$library = WP_Font_Library::get_instance();
$library->unregister_font_collection( 'google-fonts' );

get_font_collections()

Gets all registered font collections.

public function get_font_collections(): array

Returns: Array of WP_Font_Collection objects keyed by slug.

Example:

$library = WP_Font_Library::get_instance();
$collections = $library->get_font_collections();

foreach ( $collections as $slug => $collection ) {
    $data = $collection->get_data();
    echo $data['name'];
}

get_font_collection()

Gets a specific font collection.

public function get_font_collection( string $slug ): ?WP_Font_Collection

Parameters:

Returns: WP_Font_Collection or null if not found.

Example:

$library = WP_Font_Library::get_instance();
$google = $library->get_font_collection( 'google-fonts' );

if ( $google ) {
    $data = $google->get_data();
    // Access $data['font_families']
}

Private Methods

is_collection_registered()

Checks if a collection slug is already registered.

private function is_collection_registered( string $slug ): bool

Usage

Typically accessed via wrapper functions:

// Register
wp_register_font_collection( 'my-fonts', [...] );

// Unregister  
wp_unregister_font_collection( 'my-fonts' );

// Direct access
$library = WP_Font_Library::get_instance();
$all = $library->get_font_collections();
$one = $library->get_font_collection( 'google-fonts' );

Default Registration

WordPress registers Google Fonts by default via _wp_register_default_font_collections():

wp_register_font_collection( 'google-fonts', [
    'name'          => 'Google Fonts',
    'description'   => 'Install from Google Fonts. Fonts are copied to and served from your site.',
    'font_families' => 'https://s.w.org/images/fonts/wp-6.9/collections/google-fonts-with-preview.json',
    'categories'    => [
        [ 'name' => 'Sans Serif', 'slug' => 'sans-serif' ],
        [ 'name' => 'Display', 'slug' => 'display' ],
        [ 'name' => 'Serif', 'slug' => 'serif' ],
        [ 'name' => 'Handwriting', 'slug' => 'handwriting' ],
        [ 'name' => 'Monospace', 'slug' => 'monospace' ],
    ],
]);