Lighstreamer connection exception [iOS]

DrAma

Hello community,
I'm experiencing this kind of exception
2014-11-17 19:06:23.088 XXX [7431:607]Connecting to Lightstreamer...
2014-11-17 19:06:23.089 XXX [7431:972b][LIGHTSTREAMER] Connection closed
2014-11-17 19:06:23.092 XXX [7431:3b03]*** Terminating app due to uncaught exception 'Lightstreamer connection exception', reason: 'Connection interrupted'
*** First throw call stack:
(
0 CoreFoundation 0x026ba1e4 __exceptionPreprocess + 180
1 libobjc.A.dylib 0x01ab08e5 objc_exception_throw + 44
2 XXX 0x00139620 -[LSClient openConnectionWithInfo:delegate:] + 1011
3 XXX 0x000663f4 __54-[XXXNavigatorViewController connectToLightstreamer]_block_invoke + 68
4 libdispatch.dylib 0x036f37b8 _dispatch_call_block_and_release + 15
5 libdispatch.dylib 0x037084d0 _dispatch_client_callout + 14
6 libdispatch.dylib 0x036f6eb7 _dispatch_root_queue_drain + 291
7 libdispatch.dylib 0x036f7127 _dispatch_worker_thread2 + 39
8 libsystem_pthread.dylib 0x03a332e3 _pthread_wqthread + 801
9 libsystem_pthread.dylib 0x03a30eea start_wqthread + 30
)
libc++abi.dylib: terminating with uncaught exception of type LSPushConnectionException
The exception happens exactly while I'm doing a call to my back end web services using AFNetworking. IT's a systematic crash, what can be the cause?

gianluca.bertani

Hello,

the exception you see may be caused by a closeConnectioncalled while the client is still connecting. It's not an error condition, you may avoid crashing by surrounding the openConnection call with a @try-@catch block, e.g.:

@try {
[client openConnectionWithInfo:info delegate:self];
// Connection established

} @catch (LSPushConnectionException *e) {
// Connection failed
}

Hope this helps. Don't hesitate to ask if your need more infos.
Best regards,

Gianluca

DrAma

Thanx Gianluca, it seems to work so far.
Best regards,
Andrea

DrAma

DrAma Thanx Gianluca, it seems to work so far.
Best regards,
Andrea

Even in the try-catch block, the app still crashes, with the same exception.
If I comment the light streamer apart everything works fine.
Probably this not the only part to put in a try catch block.

gianluca.bertani

Hello,

the library documentation specifies, for each API call, the exceptions it may throw. LSPushConnectionException may be raised in a number of situations, in particular when an API call is made that requires a connection (e.g. subscriptions, send messages, etc.) and there is no connection available. Check the documentation, and don't hesitate to ask if you have any doubt.

Best regards,

Gianluca

DrAma

Thank you Gianluca, we arranged wrapping almost every call to lighstreamer around a try-catch

DrAma

Since I'm using it for a while I can say that this library throws a lot of exception, that make really difficult to use it.
I wrapped almost avery call to the light streamer into a try catch, it doesn't feel good.
My suggestion is to change that behavior converting inside exceptions into NSError objects as most COCOA libraries does.
Best regards,
Andrea

Alessandro Alinone

Hi Andrea,

Thanks for your suggestions. We are taking them in serious consideration. We will ponder on this topic for a couple weeks. We will let you know any news on this.

Cheers,

Alessandro

Alessandro Alinone

The discussion goes on here: http://forums.lightstreamer.com/showthread.php?4726-Exception&p=9454#post9454