Connection not found when processing reply GenericMessage

Question

Try to set up Spring Boot TCP Server with spring-integration-ip, but when send message to the server always get the error message:

2021-06-03 23:58:36.916 ERROR 35752 --- [pool-1-thread-4] o.s.i.ip.tcp.TcpInboundGateway           : Connection not found when processing reply GenericMessage [payload=byte[5], headers={ip_tcp_remotePort=51436, ip_connectionId=localhost:51436:10001:dbc9ca03-a509-4a66-9bbd-020478794bbd, ip_localInetAddress=/0:0:0:0:0:0:0:1, ip_address=0:0:0:0:0:0:0:1, id=3c446dc8-f417-e387-a4e4-42c023da0d4f, ip_hostname=localhost, timestamp=1622746716916}] for GenericMessage [payload=byte[3], headers={ip_tcp_remotePort=51436, ip_connectionId=localhost:51436:10001:dbc9ca03-a509-4a66-9bbd-020478794bbd, ip_localInetAddress=/0:0:0:0:0:0:0:1, ip_address=0:0:0:0:0:0:0:1, id=59caa1c3-20df-57c0-d1dc-81c2b0adfe0d, ip_hostname=localhost, timestamp=1622746716916}]

Here is my TcpServerConfig file:

@Configuration
@EnableIntegration
public class TcpServerConfig {

    @Value("${tcp.server.port}")
    private int port;

    @Bean
    public AbstractServerConnectionFactory serverConnectionFactory() {
        TcpNioServerConnectionFactory serverConnectionFactory = new TcpNioServerConnectionFactory(port);
        serverConnectionFactory.setUsingDirectBuffers(true);
        return serverConnectionFactory;
    }

    @Bean
    public MessageChannel inboundChannel() {
        return new DirectChannel();
    }

    @Bean
    public TcpInboundGateway inboundGateway(AbstractServerConnectionFactory serverConnectionFactory,
                                            MessageChannel inboundChannel) {
        TcpInboundGateway tcpInboundGateway = new TcpInboundGateway();
        tcpInboundGateway.setConnectionFactory(serverConnectionFactory);
        tcpInboundGateway.setRequestChannel(inboundChannel);
        return tcpInboundGateway;
    }
}

And TcpServerEnpoint file:

@Component
@MessageEndpoint
public class TcpServerEndpoint {

    @ServiceActivator(inputChannel = "inboundChannel")
    public byte[] process(byte[] message) {
        System.out.println(Arrays.toString(message));
        return "Hello".getBytes();
    }
}

I'm trying to make simple request -> response TCP server. When message has been sent it print out in debug console, but also throws the error.

Any chances to have that simple Spring Boot project from you to play with on our side and reproduce? — Artem Bilan, Jun 04 '21 at 15:47
It is simple tcp server, only 2 files and spring-integration-ip in maven dependencies list. That’s all. — Ruslan Skaldin, Jun 04 '21 at 17:12
Well, but still what you show must work as out-of-the-box. If it doesn't, then there is something fishy. So, would be great if we investigate an issue on the same environment. For example: how you test this solution would be really crucial. Thanks for understanding. — Artem Bilan, Jun 04 '21 at 17:32
@ArtemBilan the project is simple, OS is MacOS, put it on GitHub https://github.com/RussellSk/spring-tcp-server — Ruslan Skaldin, Jun 05 '21 at 08:22
I try to move my Netty project to spring-integration-ip. Thank you for helping, I understand that problem might be in serializer and deserializer, but don't get what should I do. I use this command in Netty project and try to achieve it working with spring-integration-ip, command example: echo -ne "\x01\x02" | nc localhost 8080 | hexdump -v -e "%02X" — Ruslan Skaldin, Jun 05 '21 at 14:06

score 0 · Accepted Answer · answered Jun 04 '21 at 20:41

Here is what I have for you:

@SpringBootApplication
public class So67827589Application {

    public static void main(String[] args) {
        SpringApplication.run(So67827589Application.class, args);
    }

    @Bean
    public AbstractServerConnectionFactory serverConnectionFactory() {
        TcpNioServerConnectionFactory serverConnectionFactory = new TcpNioServerConnectionFactory(7777);
        serverConnectionFactory.setUsingDirectBuffers(true);
        return serverConnectionFactory;
    }

    @Bean
    public MessageChannel inboundChannel() {
        return new DirectChannel();
    }

    @Bean
    public TcpInboundGateway inboundGateway(AbstractServerConnectionFactory serverConnectionFactory,
            MessageChannel inboundChannel) {

        TcpInboundGateway tcpInboundGateway = new TcpInboundGateway();
        tcpInboundGateway.setConnectionFactory(serverConnectionFactory);
        tcpInboundGateway.setRequestChannel(inboundChannel);
        return tcpInboundGateway;
    }

    @ServiceActivator(inputChannel = "inboundChannel")
    public byte[] process(byte[] message) {
        System.out.println(Arrays.toString(message));
        return "Hello".getBytes();
    }

}

Then I go to command line and do:

telnet localhost 7777

and type anything and get Hello back. Then I can type more and more - and Hello comes back to me. Always!

So, everything works as expected. Spring Boot 2.5.0.

The provided solution gives the same result with error. I suppose there should be outboundChannel as well as inboundChannel. — Ruslan Skaldin, Jun 06 '21 at 08:48
Well, you indeed need to be sure that your client sends the delimiter exactly what server expects. The telnet util sends a `\n\r` which is a default for those connection factories in Spring Integration. See docs about serializers: https://docs.spring.io/spring-integration/docs/current/reference/html/ip.html#tcp-codecs — Artem Bilan, Jun 06 '21 at 10:37
Please write your answer (not in comment) so I can mark it as accepted. Solve my problem, thank you. — Ruslan Skaldin, Jun 06 '21 at 10:55
Well, we are in the answer with you right now: the comments to the answer add to its matter. Your question was about Spring Integration not working - my original answer proves opposite. The incompatibility with the client is a different story you didn’t mention in the beginning . But yeah, enough of that. Glad you fixed your problem! — Artem Bilan, Jun 06 '21 at 11:00

Connection not found when processing reply GenericMessage

1 Answers1