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Nima on native-image - second request blocked forever

See original GitHub issue


OS	win11
JDK	GraalVM CE 23.0.0-dev (build 19+36-jvmci-23.0-b01)
Helidon	4.0.0-alpha2

The second request will be blocking when using Helidon Nima native image.

Main


public class Main {

  public static void main(String[] args) {

    // 启动完毕后退出 主要用来查看启动耗时
//    System.setProperty("exit.on.started", "!");

    // SE 下需要在运行入口处初始化 logging
    LogConfig.configureRuntime();

    configureJackson();

    var server = WebServer.builder()
      .socket("h1", (sb, rb) -> {
//        sb.port(8080); // overrides the config from app.properties
        var routing = HttpRouting.builder()
          .update(Main::configureRouting)
          .build();
        rb.addRouting(routing);
      })
      .start();
  }

  static ObjectMapper JSON;

  static void configureJackson() {
    JSON = ObjectMapperCustomFn.createDefault().apply(new ObjectMapper());
  }

  static void configureRouting(HttpRouting.Builder routing) {
    // noinspection unchecked
    routing.register("/info", InfoRoute::new);
  }

}

Routing

public class InfoRoute implements HttpService {

  @Override
  public void routing(HttpRules rules) {
    rules.get("", this::getInfo);
  }

  void getInfo(ServerRequest req,
               ServerResponse res) {
    var info = SystemInfo.create();
    res.headers().contentType(HttpMediaType.APPLICATION_JSON);
    res.send(info);
  }
}

Jackson media support

public class JacksonSupportProvider implements MediaSupportProvider {

  private static final System.Logger LOGGER = System.getLogger(JacksonSupportProvider.class.getName());

  <T> boolean checkSupported(GenericType<T> type,
                             Headers requestHeaders,
                             WritableHeaders<?> responseHeaders) {
    if (responseHeaders != null
        && responseHeaders.contentType().filter(v -> v.test(APPLICATION_JSON)).isPresent()) {
      return true;
    }
    return requestHeaders != null && requestHeaders.acceptedTypes().contains(APPLICATION_JSON);
  }

  @Override
  public <T> WriterResponse<T> writer(GenericType<T> type,
                                      WritableHeaders<?> requestHeaders) {

    return writer(type, requestHeaders, null);
  }

  @Override
  public <T> WriterResponse<T> writer(GenericType<T> type,
                                      Headers requestHeaders,
                                      WritableHeaders<?> responseHeaders) {
    LOGGER.log(TRACE, " writer for type=" + type.getTypeName());

    if (checkSupported(type, requestHeaders, responseHeaders)) {
      //noinspection unchecked
      return new WriterResponse<>(COMPATIBLE, () -> (EntityWriter<T>) JacksonEntityWriter.INSTANCE);
    }
    return WriterResponse.unsupported();
  }

  static class JacksonEntityWriter<T> implements EntityWriter<T> {

    private static final JacksonEntityWriter<?> INSTANCE = new JacksonEntityWriter<>();

    @Override
    public void write(GenericType<T> type,
                      T object,
                      OutputStream outputStream,
                      Headers requestHeaders,
                      WritableHeaders<?> responseHeaders) {
      try {
        Main.JSON.writeValue(outputStream, object);
      } catch (IOException e) {
        throw new RuntimeException(e);
      }
    }

    @Override
    public void write(GenericType<T> type,
                      T object,
                      OutputStream outputStream,
                      WritableHeaders<?> headers) {
      write(type, object, outputStream, headers, null);
    }
  }
}