使用RPC API

CapaRpcClient capaRpcClient = new CapaRpcClientBuilder().build();

  Mono<byte[]> responseMono = capaRpcClient.invokeMethod(SERVICE_APP_ID,
        "hello",
        "hello",
        HttpExtension.POST,
        null,
        TypeRef.BYTE_ARRAY);

byte[] response = responseMono.block();