Spring WebFlux-无法在HandlerAdapter中返回HTTP响应

Question

I'm trying to recreate HttpServletResponse#getWriter functionality in Spring WebFlux without success.

In Spring MVC, I would extend HandlerInterceptorAdapter , use mentioned getWriter for writing target response and return false from preHandle method. I'm trying to use the following code to recreate the same functionality. See following excerpts to see what I've tried so far without success.

@Component
public class CustomInterceptor extends RequestMappingHandlerAdapter
    @Override
    public Mono<HandlerResult> handle(ServerWebExchange exchange, Object handler) {
        exchange.getResponse().writeWith(s -> Mono.just(new SomeDto()));
        // creates Internal Server Error, custom WebExceptionHandler not called
        return Mono.error(new RuntimeException());
        // creates Internal Server Error, custom WebExceptionHandler not called
        throw new RuntimeException();
        // ignores response write
        return super.handle(exchange, handler);
    }
}

I've also tried to use a WebFilter , there is a possibility to change the response, however it's not possible to access HandlerMethod object, which is needed for further processing.

Any idea how to do this using Spring WebFlux? All ideas are welcome. Thank you.

Answer 1

It is possible to handle the request/response in the new reactive WebFilter , eg.

@Component
public class SecurityWebFilter implements WebFilter{
    @Override
    public Mono<Void> filter(ServerWebExchange exchange, WebFilterChain chain) {
        if(!exchange.getRequest().getQueryParams().containsKey("user")){
            exchange.getResponse().setStatusCode(HttpStatus.UNAUTHORIZED);
        }
        return chain.filter(exchange);
    }
}

Check my complete webfilter sample .