how to configure spring-5 “webclient (with jetty connector)” webflux with mediatype "application/x-ndjson"

Question

I am trying to access rest end point which will return response with mediatype "application/x-ndjson" header. How to consume this endpoint with spring 5 Webclient? Will it work if I set media type to "application/stream+json" in Spring 5 WebClient ?

Answer 1

You should be able to create your own Jackson2JsonDecoder with all the media types you'd like to support (including this specific mediatype).

Something like:

Jackson2JsonDecoder jsonDecoder = new Jackson2JsonDecoder(Jackson2ObjectMapperBuilder.json().build(), 
    new MimeType("application", "json"), new MimeType("application", "x-ndjson"));

And then configure this decoder directly in the WebClient while building it:

WebClient webClient = WebClient.builder().codecs(codecs -> codecs.defaultCodecs().jackson2JsonDecoder(jsonDecoder)).build();

If you're using Spring Boot, you can achieve all that with:

@Configuration
public class JsonConfiguration {

  @Bean
  public CodecCustomizer ndJsonCustomizer(ObjectMapper objectMapper) {
    Jackson2JsonDecoder jsonDecoder = new Jackson2JsonDecoder(objectMapper, 
        new MimeType("application", "json"), new MimeType("application", "x-ndjson"));
    return codecs -> codecs.defaultCodecs().jackson2JsonDecoder(jsonDecoder);
  }

}

In the future, you might not need to do that since the Spring Framework team is considering ndjson support out-of-the-box to replace stream+json.