Tryus websocket client - onMessage does not get called although connection is succesful - websocket

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).

Related

Spring AMQP - How to confirm that a message is delivered and Routed successfully?

I am looking for a way to delivery a message, and once the message is delivered (and routed) successfully, i need to perform some operations.
I have enabled publisher confirms and returns by:
spring.rabbitmq.publisher-confirm-type=correlated
spring.rabbitmq.publisher-returns=true
I have configured return and confirm callback on the rabbit template:
rabbitTemplate.setMandatory(true);
rabbitTemplate.setReturnCallback((message, replyCode, replyText, exchange, routingKey) -> {
System.out.println("Message returned");
});
rabbitTemplate.setConfirmCallback((correlationData, ack, cause) -> {
System.out.println("confirm"); //correlationData.returnedMessage has the original message
});
Here is my publish code:
CorrelationData crd = new CorrelationData(UUID.randomUUID().toString());
rabbitTemplate.convertAndSend("X-ORDERS", "ORDER_PLACED", request, crd);
crd.getFuture().addCallback(new ListenableFutureCallback<Confirm>() {
#Override
public void onFailure(Throwable throwable) {
log.info("Failure received");
}
#Override
public void onSuccess(Confirm confirm) {
if(confirm.isAck()){
log.info("Success received");
doSomethingAfterSuccess();
}}
});
Now, when i publish a message that is unable to route the message :-
rabbitTemplate's returnCallBack AND confirmCallBack are also being
called
the onSuccess(..) of the correlationData is still called with
isAck() = true
So, how can I check if the message is delivered successfully and routed?
EDIT: Found solution. The publish code :
CorrelationData crd = new CorrelationData(UUID.randomUUID().toString());
rabbitTemplate.convertAndSend("X-ORDERS", "ORDER_PLACED", request, crd);
crd.getFuture().addCallback(new ListenableFutureCallback<Confirm>() {
#Override
public void onFailure(Throwable throwable) {
log.info("Failure received");
}
#Override
public void onSuccess(Confirm confirm) {
if(confirm.isAck() && crd.getReturnedMessage == null){
log.info("Success received");
doSomethingAfterSuccess();
}}
});
basically changed the condition in onSuccess to "confirm.isAck() && crd.getReturnedMessage == null"
That is per the RabbitMQ documentation - you still get a positive ack, but it is guaranteed to be delievered after the return.
So simply check that the future.returnedMessage is not null in onSuccess().
See the documentation.
In addition, when both confirms and returns are enabled, the CorrelationData is populated with the returned message. It is guaranteed that this occurs before the future is set with the ack.

How to fix weird "channelMax" error rabbitmq rpc?

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");
}
}

odd behaviour - websocket spring - send message to user using listen / notify postgresql

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.

how to know if SimpMessagingTemplate.convertAndSend fails?

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?

How An ISO server can support concurrent requests?

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 ();
}
}

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