wpseek.com
A WordPress-centric search engine for devs and theme authors

function wp_get_global_styles_custom_css() {
	_deprecated_function( __FUNCTION__, '6.7.0', 'wp_get_global_stylesheet' );
	if ( ! wp_theme_has_theme_json() ) {
		return '';
	}
	/*
	 * Ignore cache when the development mode is set to 'theme', so it doesn't interfere with the theme
	 * developer's workflow.
	 */
	$can_use_cached = ! wp_is_development_mode( 'theme' );

	/*
	 * By using the 'theme_json' group, this data is marked to be non-persistent across requests.
	 * @see `wp_cache_add_non_persistent_groups()`.
	 *
	 * The rationale for this is to make sure derived data from theme.json
	 * is always fresh from the potential modifications done via hooks
	 * that can use dynamic data (modify the stylesheet depending on some option,
	 * settings depending on user permissions, etc.).
	 * See some of the existing hooks to modify theme.json behavior:
	 * @see https://make.wordpress.org/core/2022/10/10/filters-for-theme-json-data/
	 *
	 * A different alternative considered was to invalidate the cache upon certain
	 * events such as options add/update/delete, user meta, etc.
	 * It was judged not enough, hence this approach.
	 * @see https://github.com/WordPress/gutenberg/pull/45372
	 */
	$cache_key   = 'wp_get_global_styles_custom_css';
	$cache_group = 'theme_json';
	if ( $can_use_cached ) {
		$cached = wp_cache_get( $cache_key, $cache_group );
		if ( $cached ) {
			return $cached;
		}
	}

	$tree       = WP_Theme_JSON_Resolver::get_merged_data();
	$stylesheet = $tree->get_custom_css();

	if ( $can_use_cached ) {
		wp_cache_set( $cache_key, $stylesheet, $cache_group );
	}

	return $stylesheet;
}