I had implemented ISO SERVER by using ASCII channel and ASCII packager and listening on a port and giving response to ISO requests.
how can i make my server that accepts concurrent requests and send the response.
Please
if you are using Q2, just deploy QServer and set the minSessions and maxSessions which its default value is 0 and 100.
here example jPOS server that handle concurent request:
http://didikhari.web.id/java/jpos-client-receive-response-specific-port/
ISOServer works with a threadpool, so you can accept concurrent requests out of the box. Every socket connection is handled by its own thread. So, I think all you have to do is assign a ISORequestListener to your ISOServer to actually process your incoming messages.
Here's a test program taken from the jPOS guide:
public class Test implements ISORequestListener {
public Test () {
super();
}
public boolean process (ISOSource source, ISOMsg m) {
try {
m.setResponseMTI ();
m.set (39, "00");
source.send (m);
} catch (ISOException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return true;
}
public static void main (String[] args) throws Exception {
Logger logger = new Logger ();
logger.addListener (new SimpleLogListener (System.out));
ServerChannel channel = new XMLChannel (new XMLPackager());
((LogSource)channel).setLogger (logger, "channel");
ISOServer server = new ISOServer (8000, channel, null);
server.setLogger (logger, "server");
server.addISORequestListener (new Test ());
new Thread (server).start ();
}
}
Related
I created simple client and server. Client sends rpc requests:
RabbitTemplate template.convertSendAndReceive(...) ;
Server receive it, and answers back:
#RabbitListener(queues = "#{queue.getName()}")
public Object handler(#Payload String key)...
Then I make client send rpc requests asynchronously, simultaneously(which produces lot of concurrent rpc requests).
And unexpectedly receive an error:
org.springframework.amqp.AmqpResourceNotAvailableException: The channelMax limit is reached. Try later.
at org.springframework.amqp.rabbit.connection.SimpleConnection.createChannel(SimpleConnection.java:59)
at org.springframework.amqp.rabbit.connection.CachingConnectionFactory$ChannelCachingConnectionProxy.createBareChannel(CachingConnectionFactory.java:1208)
at org.springframework.amqp.rabbit.connection.CachingConnectionFactory$ChannelCachingConnectionProxy.access$200(CachingConnectionFactory.java:1196)
at org.springframework.amqp.rabbit.connection.CachingConnectionFactory.doCreateBareChannel(CachingConnectionFactory.java:599)
at org.springframework.amqp.rabbit.connection.CachingConnectionFactory.createBareChannel(CachingConnectionFactory.java:582)
at org.springframework.amqp.rabbit.connection.CachingConnectionFactory.getCachedChannelProxy(CachingConnectionFactory.java:552)
at org.springframework.amqp.rabbit.connection.CachingConnectionFactory.getChannel(CachingConnectionFactory.java:534)
at org.springframework.amqp.rabbit.connection.CachingConnectionFactory.access$1400(CachingConnectionFactory.java:99)
at org.springframework.amqp.rabbit.connection.CachingConnectionFactory$ChannelCachingConnectionProxy.createChannel
Rabbitmq client seems create too many channels. How to fix it?
And why my client create them so many?
Channels are cached so there should only be as many channels as there are actual RPC calls in process.
You may need to increase the channel max setting on the broker.
EDIT
If your RPC calls are long-lived, you can reduce the time the channel is used by using the AsyncRabbitTemplate with an explicit reply queue, and avoid using the direct reply-to feature.
See the documentation.
EDIT2
Here is an example using the AsyncRabbitTemplate; it sends 1000 messages on 100 threads (and the consumer has 100 threads).
The total number of channels used was 107 - 100 for the consumers and only 7 were used for sending.
#SpringBootApplication
public class So56126654Application {
public static void main(String[] args) {
SpringApplication.run(So56126654Application.class, args);
}
#RabbitListener(queues = "so56126654", concurrency = "100")
public String slowService(String in) throws InterruptedException {
Thread.sleep(5_000L);
return in.toUpperCase();
}
#Bean
public ApplicationRunner runner(AsyncRabbitTemplate asyncTemplate) {
ExecutorService exec = Executors.newFixedThreadPool(100);
return args -> {
System.out.println(asyncTemplate.convertSendAndReceive("foo").get());
for (int i = 0; i < 1000; i++) {
int n = i;
exec.execute(() -> {
RabbitConverterFuture<Object> future = asyncTemplate.convertSendAndReceive("foo" + n);
try {
System.out.println(future.get(10, TimeUnit.SECONDS));
}
catch (InterruptedException e) {
Thread.currentThread().interrupt();
e.printStackTrace();
}
catch (ExecutionException e) {
e.printStackTrace();
}
catch (TimeoutException e) {
e.printStackTrace();
}
});
}
};
}
#Bean
public AsyncRabbitTemplate asyncTemplate(ConnectionFactory connectionFactory) {
return new AsyncRabbitTemplate(connectionFactory, "", "so56126654", "so56126654-replies");
}
#Bean
public Queue queue() {
return new Queue("so56126654");
}
#Bean
public Queue reeplyQueue() {
return new Queue("so56126654-replies");
}
}
I am experiencing an odd behavior of my spring boot websocket set-up.
Sometimes it works, sometimes it doesn't, it just feels random.
I have tried the several setups, none proved solid: I moved the last piece of code in a commandlinerunner inside the primary class of the application and the last choice was a different class with #Component annotation.
My setup is the following: I use a jdbc driver (pgjdbc-ng) to use the listen notify function of postgres.I have a function and a trigger that listens to a specific postgres table for inserations. If any occur, notifications are sent through the websocket. The other and is an angular app that uses ng2-stompjs to listen to /topic/notificari for notifications. I am not posting the code because the notifications don't get out of spring, the angular is not the problem.
Kind regards,
This is my WebSocketConfiguration
Override
public void configureMessageBroker(MessageBrokerRegistry registry) {
registry.enableSimpleBroker("/topic", "/queue", "/user", "/notificari");
registry.setApplicationDestinationPrefixes("/app");
registry.setUserDestinationPrefix("/user");
}
#Override
public void registerStompEndpoints(StompEndpointRegistry registry) {
registry.addEndpoint("/socket").setAllowedOrigins("*")
.setHandshakeHandler(new CustomHandshakeHandler());
}
I am using a class ListenNotify and the JDBC driver pgjdbc-ng to connect to the postgresql db and use listen notify functionality
public class ListenNotify {
private BlockingQueue queue = new ArrayBlockingQueue(20);
PGConnection connection;
public ListenNotify() {
PGNotificationListener listener = new PGNotificationListener() {
#Override
public void notification(int processId, String channelName, String payload) {
queue.add(payload);
}
};
try {
PGDataSource dataSource = new PGDataSource();
dataSource.setHost("localhost");
dataSource.setDatabase("db");
dataSource.setPort(5432);
dataSource.setUser("user");
dataSource.setPassword("pass");
connection = (PGConnection) dataSource.getConnection();
connection.addNotificationListener(listener);
Statement statement = connection.createStatement();
statement.execute("LISTEN n_event");
statement.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
public BlockingQueue getQueue() {
return queue;
}
}
And finally this is the code that instantiate the ListenNotify object and listens to postgres for events that might trigger notifications that have to be send using websocket.
#Component
public class InstantaNotificari {
#Autowired
SimpMessagingTemplate template;
#EventListener(ApplicationReadyEvent.class)
public void runn() {
System.out.println("invocare met");
ListenNotify ln = new ListenNotify();
BlockingQueue queue = ln.getQueue();
System.out.println("the que ies "+ queue);
while (true) {
try {
String msg = (String) queue.take();
System.out.println("msg " + msg);
template.convertAndSend("/topic/notificari", msg);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}
I didn't use Spring so I can't test your code. Here is my tested version. I think this summarizes the differences -
Change to a try with resources block. This will close the connection on destruction of the class.
Move your while(true) into the try block on the Listener so that the
lines inside the try block doesn't ever get out of execution scope.
The while(true) is blocking, so it needs to be on another thread. ListenNotify extends Thread
I'm sure there are other ways of implementing and welcome corrections to any of my assumptions.
My tested, running code is in this answer JMS Websocket delayed delivery.
I am successfully connecting to a local websocket server with tyrus, but the onMessage method does not get called. I setup Fiddler as proxy in between and I see that the server responds with two messages, however, they are not printed out in my code. I more or less adapted the sampe code:
The onOpen Message is printed out
public static void createAndConnect(String channel) {
CountDownLatch messageLatch;
try {
messageLatch = new CountDownLatch(1);
final ClientEndpointConfig cec = ClientEndpointConfig.Builder.create().build();
ClientManager client = ClientManager.createClient();
client.connectToServer(new Endpoint() {
#Override
public void onOpen(Session session, EndpointConfig config) {
System.out.println("On Open and is Open " + session.isOpen());
session.addMessageHandler((Whole<String>) message -> {
System.out.println("Received message: " + message);
messageLatch.countDown();
});
}
}, cec, new URI("ws://192.168.1.248/socket.io/1/websocket/" + channel));
messageLatch.await(5, TimeUnit.SECONDS); //I also tried increasing timeout to 30sec, doesn't help
} catch (Exception e) {
e.printStackTrace();
}
}
That's a known issue - it will work if you rewrite lambda to anonymous class or use Session#addMessageHandler(Class, MessageHandler) (you can use lambdas here).
I am using the Spring implementation for websocket+stomp as server, and the SockJS as client. This works perfectly when the connection is fine. But I am trying to keep the messag resending when the connection is broken. Here is my code.
public void reliableSend(String target, Object data){
try{
simpMessagingTemplate.convertAndSend(target, data);
}
catch (MessagingException e){
e.printStackTrace();
timer.purge();
TimerTask task = new TimerTask() {
#Override
public void run() {
reliableSend(target, data);
}
};
timer.schedule(task, 1000);
}
}
My problem is I just cannot know convertAndSend fails, it won't throw MessagingException even I have disconnected the network and the websocket connection is broken. Is there a way I can know the failure?
I have some web services exposed using spring web services.
I would like to set a maximun timeout on server side, I mean, when a client invokes my web service It could not last more than a fixed time. Is it possible?
I have found lot of information about client timeouts, but not server timeout.
This is set at the level of the server itself and not the application, so it's application server dependent.
The reason for this is that it's the server code that opens the listening socket used by the HTTP connection, so only the server code can set a timeout by passing it to the socket API call that starts listening to a given port.
As an example, this is how to do it in Tomcat in file server.xml:
<Connector connectionTimeout="20000" ... />
You can work around this issue by making the web service server trigger the real work on another thread and countdown the time out it self and return failure if timed out.
Here is an example of how you can do it, it should time out after 10 seconds:
public class Test {
private static final int ONE_SECOND = 1_000;
public String webserviceMethod(String request) {
AtomicInteger counter = new AtomicInteger(0);
final ResponseHolder responseHolder = new ResponseHolder();
// Create another thread
Runnable worker = () -> {
// Do Actual work...
responseHolder.finished = true;
responseHolder.response = "Done"; // Actual response
};
new Thread(worker).start();
while (counter.addAndGet(1) < 10) {
try {
Thread.sleep(ONE_SECOND);
} catch (InterruptedException e) {
e.printStackTrace();
}
if (responseHolder.finished) {
return responseHolder.response;
}
}
return "Operation Timeout"; // Can throw exception here
}
private final class ResponseHolder {
private boolean finished;
private String response; // Can be any type of response needed
}
}