SocketEnginePollable Crash Sometimes

[jose-roberto-abreu]

Sometimes the app crash in the class (SocketEnginePollable), in the next method,

doRequest(req:NSURLRequest, withCallback callback: (NSData?, NSURLResponse?, NSError?) -> Void)

Specifically when calling:
session?.dataTaskWithRequest(req, completionHandler: callback).resume().

I'm using version 5.5.0, the last part of the log that I receive:

Log
2016-04-26 17:14:14.824 Logic[479:93592] *** Terminating app due to uncaught exception 'NSGenericException', reason: 'Task created in a session that has been invalidated' *** First throw call stack: (0x2293e2eb 0x2210adff 0x22e3f77d 0x22e40463 0x10e168 0x10db58 0x10d9ec 0x18acf8 0x18cb38 0x18cee4 0x1121b4 0x10f36c 0x231040 0x22aecbf 0x22b95c3 0x22b1efb 0x22baab7 0x22ba909 0x22674e0d 0x226749fc) libc++abi.dylib: terminating with uncaught exception of type NSException 2016-04-26 17:14:14.826 Logic[479:93566] LOG SocketEngine: Got message: 0{"sid":"_towWQV4p66lC-UeAAVf","upgrades":["websocket"],"pingInterval":25000,"pingTimeout":60000} 2016-04-26 17:14:14.823 Logic[479:93918] LOG SocketEngine: Got message: 40 2016-04-26 17:14:14.854 Logic[479:92712] LOG SocketIOClient: Disconnected: Ping timeout 2016-04-26 17:14:14.854 Logic[479:92712] LOG SocketEngine: Engine is being closed. 2016-04-26 17:14:14.855 Logic[479:92712] LOG SocketEnginePolling: Created POST string: 1:1

[nuclearace]

Does it still happen in 6.1.0? My guess is doRequest isn't being called from the right dispatch_queue

[nuclearace]

@MishraVikas1 Do you have any more on this? Like what request is causing it?

[MishraVikas1]

Its happening in 6.1.0 as well. In SocketEngine.swift, there is a method named disconnect() which is calling do request method.
Crash only occurs when network keeps fluctuating.

[nuclearace]

That's weird because doRequest has a check against invalidation.

[aligermiyanoglu]

Hi,

I am experiencing similar issue, you can check on:
http://crashes.to/s/b20e5c6a150

Best

[px751]

Same problem here ! Here is the log if needed. Please ask if you need more infos

SocketIOSwift Version : 6.1.0

[nuclearace]

@px751 When does this happen? Theoretically doRequest should check against invalidation. So my guess is something is invalidating on another queue. Also the line numbers in that log are a little wonky I think.

[px751]

I dont really know, it seems to be when the app disconnects...
Here are the details : http://crashes.to/s/77c635c5d77
I dont really know how to reproduce this problem but we have more that 100 users who are impacted, almost all on iOS 9.

I call the SocketIO diconnect function when the user leaves the app, maybe this comes from there, the app is kind of already in background and the background task crashes (?)

[px751]

@nuclearace Please tell me when I can make this issues private, I dont like having these info on a free access on a application in production :)

[px751]

I the [socketClient diconnect] this in the "- (void)applicationDidEnterBackground:(UIApplication *)application" function, this class is a singelton

Just before I stop the localisation service, and save the user class, but I dont think this is linked

Oh, and I dont know if this information is important, but my app is in Obj-c, not swift

FYI, the server is using SocketIO version ~1.3.2

[px751]

I've tries to debug but It seems that the function is not called when the socket io disconnects, but only at connexion or re-connexion, I am going to try to crash the server and see if this comes from this part

[nuclearace]

Yeah, this one might be tough to debug

[px751]

Let me know if you have a clue so I can test

[nuclearace]

Well something is calling stopPolling() after this code path gets past the check. Are you adding a new socket after you call disconnect?