Reading resource from classpath in Spring WebFlux

Question

I am working on SpringWebflux application and trying read a JSON file that is stored on the classpath. But I want to do it in a non-blocking way and having a problem.

Whatever I could come up with is doing it like this:

    @Override
    public Flux<SomePojo> getData() {
        Flux<DataBuffer> data = DataBufferUtils.readInputStream(() -> {
            return new ClassPathResource("config/someData.json").getInputStream();
        }, new DefaultDataBufferFactory(), 4096);

        return jackson2JsonDecoder
                .decode(data, ResolvableType.forClass(SomePojo.class), MimeType.valueOf(MediaType.APPLICATION_JSON_VALUE), null)
                .map(SomePojo.class::cast);
    }

jackson2JsonDecoder is created as bean with default ObjectMapper that comes from Spring.

    @Bean
    public Jackson2JsonDecoder jackson2JsonDecoder(ObjectMapper objectMapper) {
        return new Jackson2JsonDecoder(objectMapper);
    }

However that gives me an error and I can't figure out why:

org.springframework.core.codec.DecodingException: JSON decoding error: Already closed, can not feed more input
    at org.springframework.http.codec.json.Jackson2Tokenizer.tokenize(Jackson2Tokenizer.java:113) ~[spring-web-6.1.3.jar:6.1.3]
    Suppressed: reactor.core.publisher.FluxOnAssembly$OnAssemblyException: 
Error has been observed at the following site(s):

Any idea?