Method writeAndFlushWith(body) is not invoked in ClientHttpRequestDecorator when doing a @POST call with request @Body Flux using @RetrofitClient with WebClient

[dante-ricalde]

Hi guys, @OlgaMaciaszek
I am trying to implement a decorator to ClientHttpRequestDecorator to print some logs using @RetrofitClient @Body with Flux for the request body using WebClient, but it is not working. The method writeWith(body: Publisher) of the decorator is being invoked (actually this method should have been invoked: writeAndFlushWith()) and it doesn't receive correctly the data buffers causing the logs are not printed correctly, only the text {"prefetch":-1} is printed as request body.

I am trying with the following Retrofit Client:

    @Headers(*["Content-Type: application/stream+json", "Accept: application/stream+json"])
    @Streaming
    @POST("cards/search-stream")
    fun searchStream(@Body cardsSearchAllRequest: Flux<Card>): Flux<Card>

Note:
The method writeAndFlushWith() is being invoked and works correctly when an http request is invoked directly using WebClient (but We would like to use the component @RetrofitClient and not just the WebClient directly), like this:

    val webClient =
    WebClient.builder().baseUrl("http://localhost:8082/support/cards/v1").defaultHeader("Content-Type", "application/stream+json").clientConnector(
            DefaultReactorClientHttpConnectorDecorator(
                    ReactorClientHttpConnector(HttpClient.create()), { -> true}))
            .build()
    return webClient
            .post()
            .uri("/cards/search-stream")
            .header(org.springframework.http.HttpHeaders.CONTENT_TYPE, MediaType.APPLICATION_STREAM_JSON_VALUE)
            .header("caller-name", "web-client")
            .header("Request-ID", "550e8400-1234-41d4-a716-446655440025")
            .body(Flux.just(Card("a", "b"), Card("c", "d"), Card("e", "f"), Card("g", "h")), Card::class.java)
            .retrieve()
            .bodyToMono(Card::class.java);

We want to know if there is a bug for this scenery or there is not still support for making this type of call: @post call with request @Body Flux using @RetrofitClient(WebClient)?

I am looking forward to hearing from you!