V3DinosaurTransformer.kt

override fun transformRequestObjectNodeReactive(
  requestBody: ObjectNode
): Mono<ObjectNode> {
    return if (requestBody.get("periods").isArray) {
        val periods = (requestBody.get("periods") as ArrayNode).elements().asSequence().joinToString(",")
        webClient
          .get()
          .uri("http://localhost/periods?code=${periods}")
          .retrieve()
          .bodyToMono<ArrayNode>()
          .map { periodsBody ->
              val periodIds:List<JsonNode> = periodsBody.elements().asSequence().map {it["id"]}.toList()
              requestBody.set<ArrayNode>("periods", objectMapper.createArrayNode().addAll(periodIds))
              requestBody
          }
    } else Mono.just(requestBody)
}