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Spring Integration : No publisher available to publish TCP Connection related events

I am using Spring Integration with Spring Boot. I have a TCP Client [TcpNetClientConnectionFactory] with TcpOutboundGateway setup. I can see the below warnings in Production[No publisher available to publish].
Log Snippet
Based on my checking this warning is shown when the org.springframework.context.ApplicationEventPublisher is null.
Code:
#Bean
#ServiceActivator(inputChannel = "a04A08OutgoingChannel")
public MessageHandler a04A08OutgoingGate() {
final TcpOutboundGateway gate = new TcpOutboundGateway();
// Connection configured in client mode to send the message over the TCP socket
// and wait for acknowledgement
gate.setConnectionFactory(connectionFactory.connectionFactory(host, port));
gate.setReplyChannelName("a04A08ReplyToString");
gate.setRemoteTimeout(60_000);
return gate;
}
#Transformer(inputChannel = "a04A08ReplyToString")
public String transform(byte[] bytes) {
String reply = new String(bytes);
log.debug("transform - a04A08ReplyToString channel " + reply);
return new String(bytes);
}
public String outgoingMessage(String message) {
String reply = null;
log.info("Message being Sent : " + message);
try {
// Send the message to the TCP socket and wait for acknowledgement
reply = a04a08OutgoingGateway.sendMessage(message);
} catch (ConnectException e) {
log.error(e.getMessage(),e);
}
log.info("Acknowledgement received : " + reply);
return reply;
}
ConnectionFactory.java:
public AbstractClientConnectionFactory connectionFactory(String host, int port) {
final AbstractClientConnectionFactory connectionFactory = new TcpNetClientConnectionFactory(host, port);
connectionFactory.setSerializer(customDeserializer);
connectionFactory.setDeserializer(customDeserializer);
//connectionFactory.setSoKeepAlive(true);
connectionFactory.setSingleUse(true);// This property when set to false ensures that one shared connection is used for all
// request/replies and each caller blocks waiting for the socket
return connectionFactory;
}
Edit 1 : Included CustomDeserializer.java
#Override
public void serialize(String object, OutputStream outputStream) throws IOException {
log.info("[Serialize] Serializing data : length ==> " + object.length());
outputStream.write(object.getBytes());
log.info("[Serialize] data posted to stream");
}
#Override
public byte[] deserialize(InputStream inputStream) throws IOException {
log.info("[Deserialize] De-Serializing data");
BufferedReader input = new BufferedReader(new InputStreamReader(inputStream));
StringBuffer stringbuffer = new StringBuffer();
while (true) {
int value = input.read();
if (value == 28) {
break;
} else {
if (value != -1) {
stringbuffer.append((char) value + "");
} else {
break;
}
}
}
log.info("[deserialize.readFromSocket()]: " + stringbuffer.toString());
return stringbuffer.toString().getBytes();
}
The TCP server is able to receive the messages sent by the TCP client. [Note: TCP server is a different system and not maintained by us].I have 2 queries.
Will this warning have any impact? Can anyone elaborate on the warning? Even when the warnings are seen the messages from TCP client are sent to TCP server without any issues.
We faced below issue (Caused by: org.springframework.messaging.MessagingException: Exception while awaiting reply; nested exception is java.net.SocketTimeoutException: Read timed out) in production recently. When we faced the below exception, telnet to the server port worked but the messages were not received by the server. The issue was automatically resolved when the TCP server was restarted. My question : Is this issue related to the warning in point #1. These warnings are seen even on normal days when the messages are sent to the server without any issues.
Error logs
P.S: I also checked the post : No publisher available to publish TcpConnectionOpenEvent / TcpConnectionCloseEvent

It is not related; sounds like a server problem if restarting it solves it.
The connection factory must be declared as a #Bean so that spring can inject the event publisher.

Vertx 3 - SockJS socket opening canceled

I created a new verticle that should response for HTTP requests and SockJS bridged events. Based on this question https://stackoverflow.com/questions/41516328 and vert.x manual https://vertx.io/docs/vertx-web/java/#_sockjs I created this piece of code:
Java:
#Override
public void start(Future<Void> startFuture) throws Exception {
startHttpServer(startFuture);
startSockJSHandler();
}
private void startHttpServer(Future<Void> startFuture) {
HttpServer server = vertx.createHttpServer(new HttpServerOptions());
server.requestHandler(req -> {
System.out.println("[" + new Date().toString() + "] Request #" + ++requestCount);
if (req.path().contains("http")) {
req.response().putHeader("Access-Control-Allow-Origin", "*").end("req_num: " + requestCount);
}
}).listen(8080, ar -> startFuture.handle(ar.mapEmpty()));
}
private void startSockJSHandler() {
Router router = Router.router(vertx);
SockJSHandlerOptions sockJSOptions = new SockJSHandlerOptions().setHeartbeatInterval(2000);
SockJSHandler sockJSHandler = SockJSHandler.create(vertx, sockJSOptions);
BridgeOptions bridgeOptions = new BridgeOptions();
bridgeOptions.addInboundPermitted(new PermittedOptions().setAddressRegex(".*")).addOutboundPermitted(new PermittedOptions().setAddressRegex(".*"));
sockJSHandler.bridge(bridgeOptions, be -> {
System.out.println("BRIDGE EVENT: " + be.type().toString());
});
router.route("/eventbus/*").handler(sockJSHandler);
}
JavaScript eventbus client:
var sock = new SockJS('http://localhost:8080/eventbus/');
sock.onopen = function() {
console.log('open');
sock.send('test');
};
sock.onmessage = function(e) {
console.log('message', e.data);
sock.close();
};
sock.onclose = function() {
console.log('close');
};
HTTP request/response works fine, but SockJS events not. In web browser 'Network' module I see only one SockJS request (http://localhost:8080/eventbus/info). 8 seconds in 'pending' status, and after this time the status is changed to 'closed' (method onclose() is called at the end).
Did I do something wrong?

The HttpServer must delegate requests to the Router. Otherwise nothing happens. Usually, it is configured to delegate all requests to the Router.
server.requestHandler(router::accept).listen(8080);
See Basic Vert.x-Web concepts in the docs.

Netty Nio read the upcoming messages from ChannelFuture in Java

I am trying to use the following code which is an implementation of web sockets in Netty Nio. I have implment a JavaFx Gui and from the Gui I want to read the messages that are received from the Server or from other clients. The NettyClient code is like the following:
public static ChannelFuture callBack () throws Exception{
String host = "localhost";
int port = 8080;
try {
Bootstrap b = new Bootstrap();
b.group(workerGroup);
b.channel(NioSocketChannel.class);
b.option(ChannelOption.SO_KEEPALIVE, true);
b.handler(new ChannelInitializer<SocketChannel>() {
#Override
public void initChannel(SocketChannel ch) throws Exception {
ch.pipeline().addLast(new RequestDataEncoder(), new ResponseDataDecoder(),
new ClientHandler(i -> {
synchronized (lock) {
connectedClients = i;
lock.notifyAll();
}
}));
}
});
ChannelFuture f = b.connect(host, port).sync();
//f.channel().closeFuture().sync();
return f;
}
finally {
//workerGroup.shutdownGracefully();
}
}
public static void main(String[] args) throws Exception {
ChannelFuture ret;
ClientHandler obj = new ClientHandler(i -> {
synchronized (lock) {
connectedClients = i;
lock.notifyAll();
}
});
ret = callBack();
int connected = connectedClients;
if (connected != 2) {
System.out.println("The number if the connected clients is not two before locking");
synchronized (lock) {
while (true) {
connected = connectedClients;
if (connected == 2)
break;
System.out.println("The number if the connected clients is not two");
lock.wait();
}
}
}
System.out.println("The number if the connected clients is two: " + connected );
ret.channel().read(); // can I use that from other parts of the code in order to read the incoming messages?
}
How can I use the returned channelFuture from the callBack from other parts of my code in order to read the incoming messages? Do I need to call again callBack, or how can I received the updated message of the channel? Could I possible use from my code (inside a button event) something like ret.channel().read() (so as to take the last message)?

By reading that code,the NettyClient is used to create connection(ClientHandler ),once connect done,ClientHandler.channelActive is called by Netty,if you want send data to server,you should put some code here. if this connection get message form server, ClientHandler.channelRead is called by Netty, put your code to handle message.
You also need to read doc to know how netty encoder/decoder works.
How can I use the returned channelFuture from the callBack from other parts of my code in order to read the incoming messages?
share those ClientHandler created by NettyClient(NettyClient.java line 29)
Do I need to call again callBack, or how can I received the updated message of the channel?
if server message come,ClientHandler.channelRead is called.
Could I possible use from my code (inside a button event) something like ret.channel().read() (so as to take the last message)?
yes you could,but not a netty way,to play with netty,you write callbacks(when message come,when message sent ...),wait netty call your code,that is : the driver is netty,not you.
last,do you really need such a heavy library to do network?if not ,try This code,it simple,easy to understanding

Java websocket peer-to-peer client socket management

I am trying to build peer-to-peer cross platform chat mobile application but I am new to server programming. The server is written in java and I am using spark micro framework for server and org.java_websocket for socket connections I saw some tutorials and have implemented a class that extends WebSocketServer and I do get how the socket will work and the interface methods will get called. But I am unable to figure out a few things:
How to manage multiple clients, and how will they connect to my server. Suppose 1000 users want to connect to my server how to implement that.
If somehow I managed to connect 1000 users then if user 23 wants to chat with user 52 how will that happen.
The code I found on the tutorial requires for me to specify a port so how will I decide which port is free from my server and no other client is connected to that port and according to my knowledge only one socket can be opened on one port so how will I make my server handle millions of users (assuming I get that many).
P.S. I am using Tomcat server
The code below is what I found in the tutorial:
public class SocketHandler extends WebSocketServer {
public SocketHandler(int port) throws UnknownHostException{
super(new InetSocketAddress( port ));
}
public SocketHandler(InetSocketAddress address) throws UnknownHostException{
super(address);
}
#Override
public void onOpen( WebSocket conn, ClientHandshake handshake ) {
this.sendToAll( "new connection: " + handshake.getResourceDescriptor() );
System.out.println( conn.getRemoteSocketAddress().getAddress().getHostAddress() + " entered the room!" );
}
#Override
public void onClose( WebSocket conn, int code, String reason, boolean remote ) {
this.sendToAll( conn + " has left the room!" );
System.out.println( conn + " has left the room!" );
}
#Override
public void onMessage( WebSocket conn, String message ) {
this.sendToAll( message );
System.out.println( conn + ": " + message );
}
#Override
public void onWebsocketMessageFragment(WebSocket conn, Framedata frame) {
super.onWebsocketMessageFragment(conn, frame);
System.out.println( "received fragment: " + frame );
}
}

When to disconnect bosh connection establish from app server to use prebinding in strophe?

This question is Extension of my previous question on this SO question "How to connect XMPP bosh server using java smack library?"
I am using Java as server side language. I have successfully implement xmpp BOSH connection using smach-jbosh thanks to #Deuteu for helping me to achieve this, so far I have modify jbosh's BOSHClient.java file and added two getter method for extracting RID and SID.
Now I have RID and SID on my app server (I am using Apache Tomcat). I need to pass this credential to Strophe (web client) so that it can attach to connection.
Here I have some doubt.
When to disconnect bosh Connection establish from the app server? before passing sid, rid and jid to strophe or after passing sid, rid and jid to strophe?
As per my observation during implementation for the same, I have observed that once bosh connection from the app server has been disconnected, session is expired and SID and RID is no longer useful!!!
I have implemented this logic (Establishing bosh connection and Extracting sid and rid) on a Servlet, here once response has been send from Servlet, Thread will get expired and end BOSH connection will get terminated, so I am not able perform `Attach()` on strophe as session is expired.
Can somebody help me with that problem?

I believe #fpsColton's answer is correct - I'm just added extra info for clarity. As requested on linked thread here is the code changes I made on this - note: I only added the parts where I've labelled "DH"
In BOSHConnection:
// DH: function to preserve current api
public void login(String username, String password, String resource)
throws XMPPException {
login(username, password, resource, false);
}
// DH: Most of this is existing login function, but added prebind parameter
// to allow leaving function after all required pre-bind steps done and before
// presence stanza gets sent (sent from attach in XMPP client)
public void login(String username, String password, String resource, boolean preBind)
throws XMPPException {
if (!isConnected()) {
throw new IllegalStateException("Not connected to server.");
}
if (authenticated) {
throw new IllegalStateException("Already logged in to server.");
}
// Do partial version of nameprep on the username.
username = username.toLowerCase().trim();
String response;
if (config.isSASLAuthenticationEnabled()
&& saslAuthentication.hasNonAnonymousAuthentication()) {
// Authenticate using SASL
if (password != null) {
response = saslAuthentication.authenticate(username, password, resource);
} else {
response = saslAuthentication.authenticate(username, resource, config.getCallbackHandler());
}
} else {
// Authenticate using Non-SASL
response = new NonSASLAuthentication(this).authenticate(username, password, resource);
}
// Indicate that we're now authenticated.
authenticated = true;
anonymous = false;
// DH: Prebind only requires connect and authenticate
if (preBind) {
return;
}
// Set the user.
if (response != null) {
this.user = response;
// Update the serviceName with the one returned by the server
config.setServiceName(StringUtils.parseServer(response));
} else {
this.user = username + "#" + getServiceName();
if (resource != null) {
this.user += "/" + resource;
}
}
// Create the roster if it is not a reconnection.
if (this.roster == null) {
this.roster = new Roster(this);
}
if (config.isRosterLoadedAtLogin()) {
this.roster.reload();
}
// Set presence to online.
if (config.isSendPresence()) {
sendPacket(new Presence(Presence.Type.available));
}
// Stores the autentication for future reconnection
config.setLoginInfo(username, password, resource);
// If debugging is enabled, change the the debug window title to include
// the
// name we are now logged-in as.l
if (config.isDebuggerEnabled() && debugger != null) {
debugger.userHasLogged(user);
}
}
and
// DH
#Override
public void disconnect() {
client.close();
}
then my Client-side (Web Server) wrapper class - for connecting from within JSP is:
Note: This is proving code rather than production - so there's some stuff in here you may not want.
public class SmackBoshConnector {
private String sessionID = null;
private String authID = null;
private Long requestID = 0L;
private String packetID = null;
private boolean connected = false;
public boolean connect(String userName, String password, String host, int port, final String xmppService) {
boolean success = false;
try {
Enumeration<SaslClientFactory> saslFacts = Sasl.getSaslClientFactories();
if (!saslFacts.hasMoreElements()) {
System.out.println("Sasl Provider not pre-loaded");
int added = Security.addProvider(new com.sun.security.sasl.Provider());
if (added == -1) {
System.out.println("Sasl Provider could not be loaded");
System.exit(added);
}
else {
System.out.println("Sasl Provider added");
}
}
BOSHConfiguration config = new BOSHConfiguration(false, host, port, "/http-bind/", xmppService);
BOSHConnection connection = new BOSHConnection(config);
PacketListener sndListener = new PacketListener() {
#Override
public void processPacket(Packet packet) {
SmackBoshConnector.this.packetID = packet.getPacketID();
System.out.println("Send PacketId["+packetID+"] to["+packet.toXML()+"]");
}
};
PacketListener rcvListener = new PacketListener() {
#Override
public void processPacket(Packet packet) {
SmackBoshConnector.this.packetID = packet.getPacketID();
System.out.println("Rcvd PacketId["+packetID+"] to["+packet.toXML()+"]");
}
};
PacketFilter packetFilter = new PacketFilter() {
#Override
public boolean accept(Packet packet) {
return true;
}
};
connection.addPacketSendingListener(sndListener, packetFilter);
connection.addPacketListener(rcvListener, packetFilter);
connection.connect();
// login with pre-bind only
connection.login(userName, password, "", true);
authID = connection.getConnectionID();
BOSHClient client = connection.getClient();
sessionID = client.getSid();
requestID = client.getRid();
System.out.println("Connected ["+authID+"] sid["+sessionID+"] rid["+requestID+"]");
success = true;
connected = true;
try {
Thread.yield();
Thread.sleep(500);
}
catch (InterruptedException e) {
// Ignore
}
finally {
connection.disconnect();
}
} catch (XMPPException ex) {
Logger.getLogger(SmackBoshConnector.class.getName()).log(Level.SEVERE, null, ex);
}
return success;
}
public boolean isConnected() {
return connected;
}
public String getSessionID() {
return sessionID;
}
public String getAuthID() {
return authID;
}
public String getRequestIDAsString() {
return Long.toString(requestID);
}
public String getNextRequestIDAsString() {
return Long.toString(requestID+1);
}
public static void main(String[] args) {
SmackBoshConnector bc = new SmackBoshConnector();
bc.connect("dazed", "i3ji44mj7k2qt14djct0t5o709", "192.168.2.15", 5280, "my.xmppservice.com");
}
}
I confess that I'm don't fully remember why I put the Thread.yield and Thread.sleep(1/2 sec) in here - I think - as you can see with added PacketListener - the lower level functions return after sending data and before getting a response back from the server - and if you disconnect before the server has sent it's response then it (also) causes it to clean up the session and things won't work. However it may be that, as #fpsColton says, this dicsonnect() isn't actually required.
Edit: I now remember a bit more about whay I included sleep() and yield(). I noticed that Smack library includes sleep() in several places, including XMPPConnection.shutdown() as per source. Plus in terms of yield() I had problems in my environment (Java in Oracle Database - probably untypical) when it wasn't included - as per Smack Forum Thread.
Good luck.

After you have created a BOSH session with smack and have extracted the SID+RID values, you need to pass them to Strophe's attach() and from here on out you need to let strophe deal with this connection. Once Strophe has attached, you do not want your server to be doing anything to the connection at all.
If your server side code sends any messages at all to the connection manager after strophe has attached, it's likely that it will send a invalid RID which will cause your session to terminate.
Again, once the session has been established and is usable by strophe, do not attempt to continue using it from the server side. After your server side bosh client completes authentication and you've passed the SID+RID to the page, just destroy the server side connection object, don't attempt to disconnect or anything as this will end your session.
The thing you need to remember is, unlike traditional XMPP connections over TCP, BOSH clients do NOT maintain a persistent connection to the server (this is why we use BOSH in web applications). So there is nothing to disconnect. The persistent connection is actually between the XMPP server and the BOSH connection manager, it's not something you need to deal with. So when you call disconnect from your server side BOSH client, you're telling the connection manager to end the session and close it's connection to the XMPP server, which completely defeats the purpose of creating the session in the first place.