rsocket send duplicate requests (4) each "keepAlive" interval

[RejDev]

Hello everyone,

I don't know if this is normal, but on each cycle (keepAlive interval) rsocket sends duplicate empty requests like this :
(two requests and two responses in same interval)

req > 00000000: 0000 0000 0c80 0000 0000 0000 0000       ..............
res < 00000000: 0000 0000 0c80 0000 0000 0000 0000       ..............
req > 00000000: 0000 0000 0c80 0000 0000 0000 0000       ..............
res < 00000000: 0000 0000 0c80 0000 0000 0000 0000       ..............

for this example , keepAlive = 10000, so every 10 seconds.
What's weird is that these aren't KEEPALIVE Frame (0x03)

Front Code :

const setupOptions = {
  keepAlive: 10000,
  lifetime: 180000,
  dataMimeType: 'application/json', 
  metadataMimeType: 'message/x.rsocket.routing.v0',
};

const transportOptions = {
  url: 'ws://localhost:7000/rsocket',
  wsCreator: (url: string) => {
    return new WebSocket(url);
  },
};

// Create an instance of a client
const rsocketClient = new RSocketClient({
  serializers: { data: JsonSerializer, metadata: IdentitySerializer },
  setup: setupOptions,
  transport: new RSocketWebSocketClient(transportOptions),
});

rsocketClient.connect().subscribe({
      onComplete: (socket) => {
        console.log('Connected');
      },
      onError: (error) => console.error(error),
      onSubscribe: (cancel) => {
        console.log('onSubscribe OK');
      }, 
});

Back Code (it is not important because the problem is in the connection phase) :

@Controller
public class RsocketServerController {
	@Autowired
	ObjectMapper objectMapper;

	@SuppressWarnings("unused")
	private static final Logger log = LoggerFactory.getLogger(RsocketServerController.class);

	private static final Map<String, RSocketRequester> REQUESTER_MAP = new HashMap<>();

	@MessageMapping("sayHello") // request-response
	Mono<String> sayHello(/* @Payload */ String message) { // Hooks.onErrorDropped(()->{}) ;
		System.out.println("Received request-response message: {}" + message);

		String response;
		try {
			response = objectMapper.writeValueAsString("You said: " + message);
			return Mono.just(response).log();
		} catch (JsonProcessingException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
			return Mono.empty();
		}

	}
}

Network activity :

Environment + RSocket version(s) used:

OS:
Linux: Manjaro

Front:
VueJs 3
Webpack 5 + Typescript
"@types/rsocket-core": "^0.0.7",
"@types/rsocket-tcp-client": "^0.0.1",
"@types/rsocket-websocket-client": "^0.0.4",
"@types/sockjs-client": "^1.5.1",

Back :
openjdk version "16.0.2" 2021-07-20
OpenJDK Runtime Environment (build 16.0.2+7)
OpenJDK 64-Bit Server VM (build 16.0.2+7, mixed mode)
'org.springframework.boot' version '2.5.4'
+
implementation 'org.springframework.boot:spring-boot-starter-rsocket'
implementation 'org.springframework.boot:spring-boot-starter-websocket'
implementation 'org.springframework.boot:spring-boot-starter-webflux'