Spring WebTestClient send post request without body

Hello,

It seems org.springframework.test.web.reactive.server.WebTestClient never send my body in a post http request. I currently use springboot 2.2.0.RELEASE (Spring Test 5.2.0.RELEASE). I did the following :

@Component
class UserHandler(private val userRepo: UserRepository) {

    suspend fun addUser(req: ServerRequest): ServerResponse = coroutineScope {
        val log: Logger = LoggerFactory.getLogger(UserHandler::class.java)
        log.info("TEST TEST TEST: {}", req.awaitBody()) // Here to log the body

        val userCreated: Deferred<User> = async { userRepo.save(req.awaitBody()) }
        ServerResponse.ok().json().bodyValueAndAwait(userCreated.await())
    }

}

@Configuration
class RouterConfig {

    companion object {
        const val USER_ID_PATH_PARAM = "id"
    }

    @Bean
    fun userRoutes(userHandler: UserHandler) = coRouter {
        User.USER_API_ENDPOINT.and(accept(MediaType.APPLICATION_JSON)).nest {
            POST(Strings.EMPTY, userHandler::addUser)
        }
    }
}

@WebFluxTest
@ContextConfiguration(classes = [RouterConfig::class, UserHandler::class])
class UserHandlerTests(@Autowired private val webClient: WebTestClient) {

    @MockBean
    private lateinit var userRepository: UserRepository

    @Test
    fun addCorrectUser() {
        val user1: User = User(1L, "boby@bob.bb")

        webClient.post().uri(User.USER_API_ENDPOINT).bodyValue(user1).exchange()
                .expectBody().json("{\"toto\": \"toto\"}") // What ever the result
    }
}

Then I can see in test logs, the body sent with the request :

java.lang.AssertionError: 
Expected: toto
     but none found


> POST /user
> WebTestClient-Request-Id: [5]
> Content-Type: [application/json]
> Content-Length: [47]

{"id":1,"email":"boby@bob.bb","birthDate":null}

< 500 INTERNAL_SERVER_ERROR Internal Server Error
< Content-Type: [application/json]
< Content-Length: [17704]

But in my UserHandler logs it seems the body is empty : 2019-11-20 11:31:29.549 INFO 1660 --- [er @coroutine#9] c.l.o.cash.demo.user.UserHandler : TEST TEST TEST: {}

It works if I started my apps, this issue only occurs with WebTestClient. I suspect the log is wrong, I read the exchange method definition : "Perform the exchange without a request body." but I didn't find other method to do the job. It seems anyway the exchange method takes care about the body :

public Mono<ClientResponse> exchange() {
            ClientRequest request = (this.inserter != null ?
                    initRequestBuilder().body(this.inserter).build() :
                    initRequestBuilder().build());
...

Do you have any guess ? Thank you !

Comment From: kizux

Sorry, wrong issue, my log part in UserHandler is wrong ! Just realized few seconds after created the issue