Spring 集成重新連接 TCP 發送握手

Question

我正在嘗試使用 TcpSendingMessageHandler 上的 ClientMode 來自動重新連接連接。 此連接需要保持打開狀態，因此實現重新連接 function 很重要。

private MessageChannel createNewSubflow(Message<?> message) {
        String host = (String) message.getHeaders().get("host");
        Integer port = (Integer) message.getHeaders().get("port");
        Assert.state(host != null && port != null, "host and/or port header missing");
        String hostPort = host + port;

        TcpNetClientConnectionFactory cf = new TcpNetClientConnectionFactory(host, port);
        TcpReceivingChannelAdapter messageHandler = new TcpReceivingChannelAdapter();
        cf.setLeaveOpen(true);
        TcpConnectionInterceptorFactoryChain fc = new TcpConnectionInterceptorFactoryChain();

        HelloWorldInterceptorFactory factory = new HelloWorldInterceptorFactory();
        fc.setInterceptors(new TcpConnectionInterceptorFactory[] { factory} );

        cf.setInterceptorFactoryChain(fc);
        cf.setDeserializer(new CustomSerializerDeserializer());
        messageHandler.setErrorChannel(errorChannel);
        messageHandler.setConnectionFactory(cf);
        messageHandler.setOutputChannel(outputChannel);
        TcpSendingMessageHandler handler = new TcpSendingMessageHandler();
        handler.setConnectionFactory(cf);
        handler.setClientMode(true);
        handler.setRetryInterval(5000);
        IntegrationFlow flow = f -> f.handle(handler);
        IntegrationFlowContext.IntegrationFlowRegistration flowRegistration =
                this.flowContext
                        .registration(flow)
                        .addBean(cf)
                        .id(hostPort + ".flow")
                        .register();
        MessageChannel inputChannel = flowRegistration.getInputChannel();
        this.subFlows.put(hostPort, inputChannel);
        return inputChannel;
    }

不幸的是，我需要在打開連接套接字后發送握手。

我試圖添加這篇文章中描述的消息攔截器（ 攔截器）但是當連接套接字恢復時它不會進入攔截器。

恢復套接字時收到此警告：

HelloWorldInterceptor        : No publisher available to publish TcpConnectionOpenEvent [source=HelloWorldInterceptor

Answer 1

警告來自攔截器，因為工廠未正確初始化。

您還需要為攔截器工廠添加.addBean() 。

編輯

正如評論中提到的，攔截器的替代方法就是使用事件監聽器。

我剛剛對此進行了測試，沒有發現任何問題：

@SpringBootApplication
public class So65899947Application {

    public static void main(String[] args) {
        SpringApplication.run(So65899947Application.class, args);
    }

    @Bean
    public IntegrationFlow flow() {
        return f -> f.handle(Tcp.outboundAdapter(Tcp.netClient("localhost", 1234))
                .clientMode(true)
                .retryInterval(5000));
    }

}

@Component
class InitialSender {

    private final IntegrationFlow flow;

    InitialSender(IntegrationFlow flow) {
        this.flow = flow;
    }

    @EventListener
    public void opened(TcpConnectionOpenEvent event) {
        this.flow.getInputChannel().send(new GenericMessage<>("Hello there", 
                Collections.singletonMap(IpHeaders.CONNECTION_ID, event.getConnectionId())));
    }

}

$ nc -l 1234
Hello there
^C

$ nc -l 1234
Hello there
^C

$ nc -l 1234
Hello there
^C

$ nc -l 1234
Hello there
^C

$ nc -l 1234
Hello there
^C

編輯2

當我將其更改為使用網關時，我的結果相同......

@SpringBootApplication
@IntegrationComponentScan
public class So65899947Application {

    public static void main(String[] args) {
        SpringApplication.run(So65899947Application.class, args);
    }

    @Bean
    public IntegrationFlow flow() {
        return f -> f.handle(Tcp.outboundAdapter(Tcp.netClient("localhost", 1234))
                .clientMode(true)
                .retryInterval(5000));
    }

}

@MessagingGateway(defaultRequestChannel = "flow.input")
interface Gate {

    void handShake(@Payload String message, @Header(IpHeaders.CONNECTION_ID) String conn);

}

@Component
class InitialSender {

    private final Gate gate;

    InitialSender(Gate gate) {
        this.gate = gate;
    }

    @EventListener
    public void opened(TcpConnectionOpenEvent event) {
        this.gate.handShake("Hello there", event.getConnectionId());
    }

}