JavaScript error "Expecting a different value" when sharing between tabs.

[DarioCrivelli]

Hello. This is not a known issue.
Does the client still work normally when you see this log?
Can you see if the log lines correspond to updates coming from the Server?
We must collect information by enriching the client log.
Please add the following block at the beginnig of your Lightstreamer-related code.

require(["SimpleLoggerProvider","ConsoleAppender","LightstreamerClient","LogMessages"], 
  function(SimpleLoggerProvider,ConsoleAppender,LightstreamerClient) {
    var loggerProvider = new SimpleLoggerProvider();
    LightstreamerClient.setLoggerProvider(loggerProvider);
    loggerProvider.addLoggerAppender(new ConsoleAppender("DEBUG","lightstreamer.sharing"));
    loggerProvider.addLoggerAppender(new ConsoleAppender("DEBUG","lightstreamer.subscriptions"));
});

Note that if you make many subscriptions the log may be huge. In that case, please try to set up a shorter test case.

[palcov]

Slave:

lightstreamer.js:495
lightstreamer.sharing | DEBUG | 11:35:04,260 | 2] Broadcasting setting to shared LightstreamerClient instances {serverAddress http://push.www.XXX.com:8080/ }
lightstreamer.sharing | DEBUG | 11:35:04,264 | 2] Broadcasting setting to shared LightstreamerClient instances {adapterSet ONLAJNY }
lightstreamer.sharing | INFO | 11:35:04,274 | 325] A sharing will now be searched {}
lightstreamer.sharing | INFO | 11:35:04,275 | 297] Start search for an engine {}
lightstreamer.sharing | DEBUG | 11:35:04,276 | 307] Searching for available sharing {}
lightstreamer.sharing | DEBUG | 11:35:04,276 | 312] check shared storage to find a valid engine {}
lightstreamer.sharing | DEBUG | 11:35:04,278 | 313] storage inspection complete {}
lightstreamer.sharing | INFO | 11:35:04,279 | 304] valid engine values found, will try to connect to it {}
lightstreamer.sharing | DEBUG | 11:35:04,279 | 315] sharing through shared worker {}
lightstreamer.sharing | INFO | 11:35:04,279 | 302] A sharing was found, this will attach to it {}
lightstreamer.sharing | INFO | 11:35:04,293 | 296] Stop search for an engine {}
lightstreamer.subscriptions | DEBUG | 11:35:04,488 | 13] Restoring all pending Subscriptions {}
lightstreamer.subscriptions | DEBUG | 11:35:04,682 | 346] Adapter Set assigned {[|Subscription|1|0||0||] COMMENTS }
lightstreamer.subscriptions | DEBUG | 11:35:04,682 | 350] Snapshot Required assigned {[|Subscription|1|0||0||] yes }
lightstreamer.subscriptions | INFO | 11:35:04,692 | 10] Subscribing subscription {[|Subscription|1|0||0||] }
lightstreamer.subscriptions | INFO | 11:35:04,693 | 336] Subscription entered the active state {[|Subscription|5|0|1|1|2|] }
lightstreamer.subscriptions | DEBUG | 11:35:04,693 | 12] sending Subscription to the engine {}
lightstreamer.subscriptions | DEBUG | 11:35:04,694 | 344] Subscription request generated {[|Subscription|5|0|1|1|2|] }
lightstreamer.subscriptions | DEBUG | 11:35:04,695 | 340] Subscription waiting to be sent to server {[|Subscription|2|0|1|2|2|] }
lightstreamer.subscriptions | DEBUG | 11:35:04,719 | 346] Adapter Set assigned {[|Subscription|1|0||0||] MATCHES }
lightstreamer.subscriptions | DEBUG | 11:35:04,720 | 350] Snapshot Required assigned {[|Subscription|1|0||0||] yes }
lightstreamer.subscriptions | INFO | 11:35:04,756 | 10] Subscribing subscription {[|Subscription|1|0||0||] }
lightstreamer.subscriptions | INFO | 11:35:04,756 | 336] Subscription entered the active state {[|Subscription|5|0|2|1|3|] }
lightstreamer.subscriptions | DEBUG | 11:35:04,756 | 12] sending Subscription to the engine {}
lightstreamer.subscriptions | DEBUG | 11:35:04,757 | 344] Subscription request generated {[|Subscription|5|0|2|1|3|] }
lightstreamer.subscriptions | DEBUG | 11:35:04,757 | 340] Subscription waiting to be sent to server {[|Subscription|2|0|2|2|3|] }
lightstreamer.subscriptions | DEBUG | 11:35:04,819 | 341] Subscription queued to be sent to server {[|Subscription|3|0|1|2|2|] }
lightstreamer.subscriptions | DEBUG | 11:35:04,820 | 341] Subscription queued to be sent to server {[|Subscription|3|0|2|2|3|] }
lightstreamer.subscriptions | INFO | 11:35:05,28 | 337] Subscription is now subscribed to {[|Subscription|4|0|2|2|3|] }
lightstreamer.js:496 weswit.test | ERROR | ibbid=BBID-01-0116789343678501311:35:17,191 | 386] Expecting a different value {4 3 }
lightstreamer.js:496 weswit.test | ERROR | ibbid=BBID-01-0116789343678501311:35:17,231 | 386] Expecting a different value {4 3 }

And here is stack trace of error:



Iam sorry for big logs, we can search for particular messages if you ask to. But as I said, we disabled sharing and problems are gone, so it is not fatal issue now.

[DarioCrivelli]

Hi, thank you for the collaboration.
The log shows that there is a message which is not received by the slave page, but we can't figure out a possible cause.
We must refine the log and, to do so, we have to provide you with an extended library.
I will send you a private message with instructions.

By the way, the log times in the "Master" and "Slave" logs don't match.
Can you confirm that they were taken at the same time?
This was not important, but will become so for logs taken with the extended library.

[DarioCrivelli]

With Palcov's help we have finally found a bug in the library code.
The bug should be limited to "slave" pages in a connection sharing scenario and is triggered by unusual delays in the execution of internal tasks; one possible cause is a heavy page startup.

If anyone experiences similar problems, until a new release of Lightstreamer with the fixed library is available, it can be downloaded here.