socketio
Failed to Connect to socket.io implemented simple server - No Specific Reason Given
Describe the bug
I continuously get a generic error upon attempting to connect with a simple socket.io implemented server; as a client. The error is: server error.
To Reproduce
Server
Socket.IO server version: unknown
Client
Socket.IO java client version: 2.0.1
public class Callback
{
private final int MAX_RECONNECTION_ATTEMPTS;
private Socket client;
private CountDownLatch awaiter;
public Callback(String url) {
MAX_RECONNECTION_ATTEMPTS = ConfigHandler.getInstance().getWebSocketSettings().getMaxConnectionRetries();
try{
client = IO.socket(
(new URI(url)),
IO.Options.builder().setTimeout(60000).build()
);
} catch (URISyntaxException e) {
System.err.println(e.getMessage());
}
awaiter = new CountDownLatch(1);
}
private void await() {
try{
awaiter.await(client.io().timeout(), TimeUnit.MILLISECONDS);
} catch (InterruptedException e) {
await();
}
}
private void resetAwaiter() {
awaiter = new CountDownLatch(1);
}
private void _connect() {
//setup lifecycle listeners:
if (!client.hasListeners(Socket.EVENT_CONNECT))
client.once(Socket.EVENT_CONNECT, ((Emitter.Listener)(args) -> {
LOG.info(
"*CaseWorker (" + ConfigHandler.getInstance().getConfig().getTestEnvironment() +
") WEBSOCKET CONNECTED*"
);
awaiter.countDown();
}));
client.once(Socket.EVENT_CONNECT_ERROR, ((Emitter.Listener)(args) -> {
StringBuilder fold = new StringBuilder();
for (Object arg : args) {
if (arg instanceof Exception)
fold.append(System.lineSeparator()).append(((Exception)arg).getMessage());
} LOG.info(
"*CaseWorker ("+ConfigHandler.getInstance().getConfig().getTestEnvironment()+
") WEBSOCKET CONNECTION ERROR*: "+fold.toString()
);
awaiter.countDown();
}));
if (!client.hasListeners(Socket.EVENT_DISCONNECT))
client.on(Socket.EVENT_DISCONNECT, ((Emitter.Listener)(args) -> {
StringBuilder fold = new StringBuilder();
for (Object arg : args) {
if (arg instanceof String)
fold.append(System.lineSeparator()).append((String)arg);
} LOG.info(
"*CaseWorker (" + ConfigHandler.getInstance().getConfig().getTestEnvironment() +
") WEBSOCKET DISCONNECTED*: " + fold.toString()
);
}));
client.open().connect();
//await connection or err:
await();
resetAwaiter();
}
public void connect() throws SocketIOException {
int remainingAttempts = MAX_RECONNECTION_ATTEMPTS;
while ((remainingAttempts > 0)&&(!client.connected())){
LOG.info(
'*'+TestHelpers.ordinalOf(MAX_RECONNECTION_ATTEMPTS - remainingAttempts + 1)+
" ATTEMPT TO ESTABLISH WEBSOCKET WITH CaseWorker ("+
ConfigHandler.getInstance().getConfig().getTestEnvironment()+")* ..."
);
_connect();
--remainingAttempts;
}
if (!client.connected())
throw new SocketIOException(
"*COULD NOT ESTABLISH WEBSOCKET WITH CaseWorker (" +
ConfigHandler.getInstance().getConfig().getTestEnvironment()+
")*");
}
public void awaitCaseUpdated(@NotNull() String caseID) throws SocketIOException {
if (client.connected()) {
client.emit("joinRoom", caseID).
once("joinRoom", ((Emitter.Listener)((msg) -> {
LOG.info("*joinRoom*: "+ Arrays.toString(msg));
//@TODO: assumption that it's the 2nd component
if (msg[1] instanceof String) {
if (((String)msg[1]).contains("caseUpdated"))
awaiter.countDown();
}
})));
await();
resetAwaiter();
} else
throw new SocketIOException("Cannot awaitCaseUpdated as not connected yet");
}
public void disconnect() throws SocketIOException {
if (client.connected())
client.disconnect().close();
else
throw new SocketIOException("cannot disconnect given no connection");
}
}
Then, this class is applied in another class:
//omitted..
//in the constructor:
callback = new Callback(
ConfigHandler.getInstance().getWebSocketSettings().getCarFinanceEndpoint() +
"&token="+getToken()
);
//omitted..
public void awaitCallbackForCase(String caseID) throws SocketIOException {
callback.connect();
callback.awaitCaseUpdated(caseID);
callback.disconnect();
}
Expected behavior Should, at least, successfully connect.
Platform:
- Device: PC (Lenovo ThinkPad)
- OS: Windows 10
Additional context
I am only trying to 'listen' on 1 event joinRoom. Then I literally just wait until some new record pattern-matches caseUpdated.
Hi! Do you know the version of the server? You can check the compatibility table here: https://socketio.github.io/socket.io-client-java/installation.html
Regarding your reconnection logic, you can listen to the events sent by the underlying Manager:
public class Fiddle {
public static void main(String[] argz) {
IO.Options options = IO.Options.builder()
.setReconnectionAttempts(10)
.build();
final Socket socket = IO.socket(URI.create("http://localhost:8080"), options);
socket.io().on(Manager.EVENT_RECONNECT_ERROR, (args) -> {
// reconnection attempt has failed
});
socket.io().on(Manager.EVENT_RECONNECT_FAILED, (args) -> {
// all reconnection attempts have failed
});
socket.connect();
}
}
Hi! Do you know the version of the server? You can check the compatibility table here: https://socketio.github.io/socket.io-client-java/installation.html
Regarding your reconnection logic, you can listen to the events sent by the underlying Manager:
public class Fiddle { public static void main(String[] argz) { IO.Options options = IO.Options.builder() .setReconnectionAttempts(10) .build(); final Socket socket = IO.socket(URI.create("http://localhost:8080"), options); socket.io().on(Manager.EVENT_RECONNECT_ERROR, (args) -> { // reconnection attempt has failed }); socket.io().on(Manager.EVENT_RECONNECT_FAILED, (args) -> { // all reconnection attempts have failed }); socket.connect(); } }
Sorry, I don't know the version of the associated server. I'll try out those extra listeners to see what new information they can provide.
Thanks.
Ok, so I applied the following 2 listeners to client which is of type Socket:
client.io().on(Manager.EVENT_RECONNECT_ERROR, (args) -> {
StringBuilder fold = new StringBuilder();
LOG.info("*WEBSOCKET RECONNECT ERROR*:");
for (Object arg : args) {
if (arg.getClass().isPrimitive())
fold.append(arg.toString());
else if (arg instanceof String)
fold.append((String)arg);
}
LOG.info(fold.toString());
});
client.io().on(Manager.EVENT_RECONNECT_FAILED, (args) -> {
StringBuilder fold = new StringBuilder();
LOG.info("*WEBSOCKET RECONNECT FAILED ERROR*:");
for (Object arg : args) {
if (arg.getClass().isPrimitive())
fold.append(arg.toString());
else if (arg instanceof String)
fold.append((String)arg);
}
LOG.info(fold.toString());
});
However, I didn't receive any new information; instead, I get the same vague server error:
Apr 23, 2022 12:35:15 PM domain.actors.CaseWorker$Callback connect
INFO: *1st ATTEMPT TO ESTABLISH WEBSOCKET WITH CaseWorker (sit)* ...
Apr 23, 2022 12:35:16 PM domain.actors.CaseWorker$Callback lambda$_connect$3
INFO: *CaseWorker (sit) WEBSOCKET CONNECTION ERROR*:
server error
Apr 23, 2022 12:35:16 PM domain.actors.CaseWorker$Callback connect
INFO: *2nd ATTEMPT TO ESTABLISH WEBSOCKET WITH CaseWorker (sit)* ...
Apr 23, 2022 12:35:17 PM domain.actors.CaseWorker$Callback lambda$_connect$3
INFO: *CaseWorker (sit) WEBSOCKET CONNECTION ERROR*:
server error
Etc..
Any idea how I can uncover the root cause?? @bazza @mdawaffe @lu-zero @b95505017 @pamepros
client.io().on(Manager.EVENT_RECONNECT_ERROR, (args) -> { StringBuilder fold = new StringBuilder(); LOG.info("WEBSOCKET RECONNECT ERROR:"); for (Object arg : args) { if (arg.getClass().isPrimitive()) fold.append(arg.toString()); else if (arg instanceof String) fold.append((String)arg); } LOG.info(fold.toString()); });
Hi，I have a question about your code：
you create
StringBuilder fold = new StringBuilder(); in socket.on()
have you tried creating a global variable to append these args? @oliTheTM
