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From Tom Nichols <tmnich...@gmail.com>
Subject Re: Dealing with session expired
Date Thu, 12 Feb 2009 19:17:56 GMT
So if a session expires, my ephemeral nodes and watches have already
disappeared?  I suppose creating a new ZK instance with the old
session ID would not do me any good in that case.  Correct?

Thanks.
-Tom



On Thu, Feb 12, 2009 at 2:12 PM, Mahadev Konar <mahadev@yahoo-inc.com> wrote:
> Hi Tom,
>  We prefer to discard the zookeeper instance if a session expires.
> Maintaining a one to one relationship between a client handle and a session
> makes it much simpler for users to understand the existence and
> disappearance of ephemeral nodes and watches created by a zookeeper client.
>
> thanks
> mahadev
>
>
> On 2/12/09 10:58 AM, "Tom Nichols" <tmnichols@gmail.com> wrote:
>
>> I've come across the situation where a ZK instance will have an
>> expired connection and therefore all operations fail.  Now AFAIK the
>> only way to recover is to create  a new ZK instance with the old
>> session ID, correct?
>>
>> Now, my problem is, the ZK instance may be shared -- not between
>> threads -- but maybe two classes in the same thread synchronize on
>> different nodes by using different watchers.  So it makes sense that
>> one ZK client instance can handle this.  Except that even if I detect
>> the session expiration by catching the KeeperException, if I want to
>> "resume" the session, I have to create a new ZK instance and pass it
>> to any classes who were previously sharing the same instance.  Does
>> this make sense so far?
>>
>> Anyway, bottom line is, it would be nice if a ZK instance could itself
>> recover a session rather than discarding that instance and creating a
>> new one.
>>
>> Thoughts?
>>
>> Thanks in advance,
>>
>> -Tom
>
>

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