Reconnecting client after error

jkrohn

We have a few clients whose IT department has installed a firewall appliance that is interfering with Lightstreamer. A few times a day they get Error 30 and get disconnected.

While we work with their IT to figure out what is going on I would like to implement a workaround on our side that suppresses the error and automatically reconnects their engine.

Is this as simple as implementing onServerError and using changeStatus to change to STREAMING?

Dario Crivelli

Yes, you just need to implement onServerError, identify the specific case and force STREAMING again.
This is not the default, because onServerError is usually called when the problem is not recoverable by a new connection attempt. For instance, the connection may have been forcibly interrupted because of a limit on the overall number of sessions.
If you reconnect in any case, consider that this may not always be the best handling of the case.

However, if a firewall simply breaks a connection, this should not cause an "Error 30". Can you find more information on what happens in those situations?
Note that, with the next release of Lightstreamer, the specific cause of the interruption will be available to the client and all available error codes, between 30 and 39, will be used.

jkrohn

What would cause Error 30? They are the only company that is reporting this as an issue.

Would there by anything in the logs to look for?

Thanks.

Dario Crivelli

The normal causes are those reported in the onServerError documentation.
Other causes are possible from the Server point of view, but they should not happen when the Web Client Library is used.

If JMX is not used or not enabled
and the Metadata Adapter does never leverage the ConflictingSessionException,
then the case should be investigated;
the corresponding Server log might contain some hint.