WebSocket Closes with Protocol Error 1002

Question

I m implementing WebSocket messages command-line client. I have checked that this error corresponds to the problem with the protocol. I upgraded ws to the newest 7.4.1. At backend I use Spring Boot Websockets at version 2.3.4.RELEASE.

The 2 main causes of this are said to be packet loss or malformed messages. I have made some checks to check those but none seem valid. The messages I test are small so it shouldn't be the case with message size. The connection is fully on localhost. I test the solution with 3 users and sometimes I get this error sometimes not.

Can someone help me figure out how to get rid of this type of error?

Here is the code I use for client to send messages:

async function test(number_of_messages, break_between_messages) {
const websocket = new WebSocket(url...)

websocket.on('message', function incoming(data) {
    console.log(getMessage("Received", data))
});

websocket.on('close', function(data) {
    console.log('Disconnected!!!! ' + data.toString());
});

const opened = await connection(websocket)

//Wait 5 seconds
await sleep(5_000);

if (opened) {
    for (i = 0; i < number_of_messages; i++) {

        for (const chatId of chatIds) {
            let content = i.toString() + " from " + user;
            let msg = JSON.stringify({
                "chatId": chatId,
                "author": user,
                "content": content
            })
            websocket.send(msg)

            let message = getMessage("Sent", msg)
            console.log(message)
        }

        await sleep(break_between_messages);
    }

} else {
    console.log("ERROR on Opening Connection")
    return
}

// Wait 1 minute
await sleep(60_000);
websocket.close()

}

With backend code:

@Component
@ServerEndpoint(value = "/webSocket/{username}",
        encoders = MessageRepresentationEncoder.class, decoders = MessageRepresentationDecoder.class)
public class MessagingSocket {
    private Logger logger = LoggerFactory.getInstance();
    private Session session;
    private MessagingAPI messagingAPI = MessagingAPIFactory.createAPI();
    private UserSocketRegistry userSocketRegistry = UserSocketRegistry.createRegistry();
    private SessionUserRegistry sessionUserRegistry = SessionUserRegistry.createRegistry();

    @OnOpen
    public void onOpen(Session session, @PathParam("username") String username) {
        this.session = session;
        logger.log(LoggingType.INFO, "Started new session " + session.getId());
        logger.log(LoggingType.INFO, username + " connected");

        userSocketRegistry.addSessionForUser(this, username);
        sessionUserRegistry.addSessionForUser(session, username);
    }

    @OnMessage //Allows the client to send message to the socket.
    public void onMessage(MessageRepresentation messageRepresentation) {
        logger.log(LoggingType.INFO, "Received " + messageRepresentation.toString());
        messagingAPI.write(WriteMessage.from(UUID.fromString(messageRepresentation.chatId), messageRepresentation.author, messageRepresentation.content));
        broadcastToChat(messageRepresentation);
    }

    private void broadcastToChat(MessageRepresentation message) {
        final List<MessagingSocket> sockets = messagingAPI.getUsersConnectedToChat(UUID.fromString(message.chatId)).stream().filter(user -> userSocketRegistry.hasSocketFor(user.getName()))
                .map(user -> userSocketRegistry.getSocketFor(user.getName())).collect(Collectors.toList());

        logger.log(LoggingType.INFO, "Starting broadcast of " + message.content + " from " + message.author + " for " + String.join(",", messagingAPI.getUsersConnectedToChat(UUID.fromString(message.chatId)).stream().map(x -> x.getName()).collect(Collectors.toList())));
        for (MessagingSocket messagingSocket : sockets) {
            logger.log(LoggingType.INFO, "Broadcasting message" + message.content + " to " + messagingSocket.session.getId());
            messagingSocket.sendMessage(message);

        }
    }

    private void sendMessage(MessageRepresentation message) {
        try {
            this.session.getBasicRemote().sendObject(message);
        } catch (IOException | EncodeException e) {
            logger.log(LoggingType.ERROR, "Caught exception while sending message to Session Id: " + this.session.getId());
        }
    }

    @OnClose
    public void onClose(Session session) {
        String user = sessionUserRegistry.getUserFor(session);
        logger.log(LoggingType.INFO, "User " + user + " with session " + this.session.getId() + " disconnected ");
        sessionUserRegistry.removeSession(session);
        userSocketRegistry.removeUser(user);
    }
}

And MessageRepresentation as:

public class MessageRepresentation {
    public String chatId;
    public String author;
    public String content;

    @Override
    public String toString() {
        return "MessageRepresentation{" +
                "chatId='" + chatId + '\'' +
                ", author='" + author + '\'' +
                ", content='" + content + '\'' +
                '}';
    }
}

After further investigation I m getting the following exception:

java.lang.IllegalStateException: The remote endpoint was in state [TEXT_FULL_WRITING] which is an invalid state for called method
at org.apache.tomcat.websocket.WsRemoteEndpointImplBase$StateMachine.checkState(WsRemoteEndpointImplBase.java:1243)
at org.apache.tomcat.websocket.WsRemoteEndpointImplBase$StateMachine.textStart(WsRemoteEndpointImplBase.java:1205)
at org.apache.tomcat.websocket.WsRemoteEndpointImplBase.sendString(WsRemoteEndpointImplBase.java:191)
at org.apache.tomcat.websocket.WsRemoteEndpointImplBase.sendObject(WsRemoteEndpointImplBase.java:600)
at org.apache.tomcat.websocket.WsRemoteEndpointBasic.sendObject(WsRemoteEndpointBasic.java:74)
at presentation.frontend.websockets.server.MessagingSocket.sendMessage(MessagingSocket.java:64)
at presentation.frontend.websockets.server.MessagingSocket.broadcastToChat(MessagingSocket.java:57)
at presentation.frontend.websockets.server.MessagingSocket.onMessage(MessagingSocket.java:47)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:566)
at org.apache.tomcat.websocket.pojo.PojoMessageHandlerWholeBase.onMessage(PojoMessageHandlerWholeBase.java:80)
at org.apache.tomcat.websocket.WsFrameBase.sendMessageText(WsFrameBase.java:402)
at org.apache.tomcat.websocket.server.WsFrameServer.sendMessageText(WsFrameServer.java:119)
at org.apache.tomcat.websocket.WsFrameBase.processDataText(WsFrameBase.java:502)
at org.apache.tomcat.websocket.WsFrameBase.processData(WsFrameBase.java:301)
at org.apache.tomcat.websocket.WsFrameBase.processInputBuffer(WsFrameBase.java:133)
at org.apache.tomcat.websocket.server.WsFrameServer.onDataAvailable(WsFrameServer.java:82)
at org.apache.tomcat.websocket.server.WsFrameServer.doOnDataAvailable(WsFrameServer.java:171)
at org.apache.tomcat.websocket.server.WsFrameServer.notifyDataAvailable(WsFrameServer.java:151)
at org.apache.tomcat.websocket.server.WsHttpUpgradeHandler.upgradeDispatch(WsHttpUpgradeHandler.java:148)
at org.apache.coyote.http11.upgrade.UpgradeProcessorInternal.dispatch(UpgradeProcessorInternal.java:54)
at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:59)
at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:868)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1590)
at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.base/java.lang.Thread.run(Thread.java:834)

java.lang.IllegalStateException: Message will not be sent because the WebSocket session has been closed

Is the `_` in the `awaits` really part of the syntax? I don't think I've ever seen that. Not that that should be causing the error you have. Could you also summarize what you do to replicate and maybe what line is the last line of functioning code before the error is thrown? — Shmack, Dec 20 '20 at 23:51
Could you refer to the exact line with the awaits comment if I understand correctly this is same use as here https://v8.dev/features/numeric-separators? I launch the server and rerun the rest as shown here then after a few messages I can see log that is in onClose section of client. It is happening like 70% of the time to on average one of agents. I use 3 agents for my tests. — Hyphen, Dec 21 '20 at 00:14
You probably should have tagged the framework you're using to attract more views specific to your question. — John, Dec 21 '20 at 00:42

score 2 · Answer 1 · answered Dec 21 '20 at 17:00

2

I could be off the mark here but I think this is probably due to the message containing invalid UTF8 or some such. i.e. malformed.

If this sounds like it could be the cause the simple fix would be to encode the msg

        let msg = JSON.stringify({
            "chatId": chatId,
            "author": user,
            "content": content
        })

to

  let msg = unescape(encodeURIComponent(JSON.stringify({
                "chatId": chatId,
                "author": user,
                "content": content
            })));

Then decode on the other side...

JSON.parse(decodeURIComponent(escape( ... )))

answered Dec 21 '20 at 17:00

Fraser

15,275
8
53
104

It looks like i m still getting some clients disconnected (here is part of log for Agent 1): [1608576813254]Received: {"chatId":"0ea9c68c-fe9a-4bc6-adc9-0068cab1b013","author":"Agent3","content":"18 from Agent3"} Disconnected!!!! 1002 – Hyphen Dec 21 '20 at 18:55
1

Since your answer may be important trace I m going to give you the bounty. I m going to check in Wireshark why message was malformed. – Hyphen Dec 21 '20 at 19:34
I have look into Wireshark while executing this test: I can see WebSocket Connection Close [FIN] and when I look into data is shows "An unrecoverable IOException occurred so the connection was closed"; this message is sent from my server to client – Hyphen Dec 22 '20 at 14:21

Hyphen · Accepted Answer · 2020-12-22T15:05:20.537

The solution to this one involved 2 steps.

1: Find the error stacktrace

@OnError
public void onError(Session session, Throwable throwable) {
    logger.log(LoggingType.ERROR, "Error for " + session.getId() + " caused by: " + throwable.getMessage());
    throwable.printStackTrace();
}

2: Change synchronous BasicRemote to asynchronous AsyncRemote in broadcasting messages (this is important when the number of messages increased)

private void sendMessage(MessageRepresentation message) {
        this.session.getAsyncRemote().sendObject(message);
    }

WebSocket Closes with Protocol Error 1002

2 Answers2