How to set headers with reactive-streams in camel?

Question

我有以下调用 camel 中的路由，我需要设置一些通过参数到达的标头，但是，to 方法只允许将数据发送到路由。在调用我的路由之前如何设置标题？

@Autowired
private CamelReactiveStreamsService camelService;

public Mono<Person> callRoute(Map<String, Object> headers, Person person) {
    return Mono.from(camelService.to("direct:myDirectRoute", person))
            .map(exchange -> exchange.getMessage().getBody(Person.class));
}