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Re: [xmlblaster] Publish/Topic clobbering with multiple clients ( found my problem)

Hallo Colin,
sorry having kept you waiting for so long.

Madere, Colin wrote: 
The problem was appearing when a client is disconnected and reconnected w/o
restarting xmlBlaster.  It seems to be that I was (incorrectly) erasing the
key upon client shutdown:

(I don't really understand what the comment here is saying.  What is meant
by "it", the oid? )
            // only erase since we don't check if it exists on init
            EraseKey ek = new EraseKey(glob, oid);
            EraseQos eq = new EraseQos(glob);
            EraseReturnQos[] eraseArr = con.erase(ek.toXml(), eq.toXml());

The behavior I noticed when this was run on one client with another still
connected and subscribed was:

If my client runs the erase code above and re-connects doing all it's init
code, it will receive updates on the topic but when it publishes, the other
client(s) which remained connected no longer receives it's updates.

Is this the expected behavior in this scenario?  Just trying to further my
understanding...

Yes that is the expected behaviour. When a client makes an erase on a topic (an oid), all subscriptions (the own subscriptions but also these done by other clients) are removed too.

So when your client reconnects and starts publishing again, the second client has no subscription on that topic anymore.

If you don't want that behaviour you should not do an erase on the topic. If this is wanted for some reason, there is an alternative: when an erase is done, all the subscribers to that topic get an 'erase' update. So these clients getting an erase event could then resubscribe to the topic.

Regards
Michele


Colin