wp_is_authorize_application_password_request_valid example

if ( ! empty( $_REQUEST['reject_url'] ) ) {
    $reject_url = $_REQUEST['reject_url'];
} elseif ( $success_url ) {
    $reject_url = add_query_arg( 'success', 'false', $success_url );
} else {
    $reject_url = null;
}

$user = wp_get_current_user();

$request  = compact( 'app_name', 'app_id', 'success_url', 'reject_url' );
$is_valid = wp_is_authorize_application_password_request_valid( $request, $user );

if ( is_wp_error( $is_valid ) ) {
    wp_die(
        __( 'The Authorize Application request is not allowed.' ) . ' ' . implode( ' ', $is_valid->get_error_messages() ),
        __( 'Cannot Authorize Application' )
    );
}

if ( wp_is_site_protected_by_basic_auth( 'front' ) ) {
    wp_die(
        __( 'Your website appears to use Basic Authentication, which is not currently compatible with application passwords.' ),