WordPress REST API theme options

rest-api-theme-options.php

<?php

add_action('rest_api_init', function () {
    register_rest_route( 'wp/v2', 'options', [
        'methods'  => 'GET',
        'callback' => 'api_theme_options'
    ]);
});

function api_theme_options($request) {
    $options = [];

    $general = get_option( 'theme_general_options' );
    foreach ($general as $key => $item) {
        $options[$key] = $item;
    }

    $response = new WP_REST_Response($options);
    $response->set_status(200);
    return $response;
}