[Zope] long running methods

[robert rottermann]

Am 20.05.2010 19:34, schrieb Maik Derstappen, Derstappen IT:
> Am 20.05.2010 16:05, schrieb Jürgen Herrmann:
>> On Thu, 20 May 2010 15:59:58 +0200, Patrick Gerken
>> <do3ccqrv at googlemail.com>  wrote:
>>
>>> On Thu, May 20, 2010 at 14:18, Jürgen Herrmann
>>> <Juergen.Herrmann at xlhost.de>wrote:
>>>
>>>
>>>> hi there!
>>>>
>>>> as our zope2 zodb grows we experience more and more conflicts
>>>> with long running transactions. so i'm going to rewrite these
>>>> methods to commit transactions in batches - here my attempt
>>>> to tackle this problem. the idea is to get a list of objects
>>>> to be modified in this transaction, break it down to batches
>>>> and commit after each batch was processed. to avoid zope's
>>>> retry-on-conflict machinery and still have a chance to retry
>>>> per batch transaction commits, the iteration over one batch
>>>> is guarded by a try:except ConflictError: and a retry logic.
>>>>
>>>>
>>> Zope already has its own retry mechanism, maybe you might want to
>>> call your long running method multiple times, each time working on the
>>> next batch.
>>>
>>>
>> in fact zope's retry machinery is kicking in too often which is a
>> bad thing if the retried transaction runs for say 30min or so.
>>
>> having to gather the list of objects outside of zope, doing the
>> batching there and calling into zope multiple times - i wanted
>> to avoid that.
>>
>> i'd like to have all the logic contained in one zope method
>> for the sake of simplicity on the caller's side (most of these
>> are kicked off by cron jobs).
>>
>> jürgen
>>
> take a look at http://pypi.python.org/pypi/affinitic.zamqp maybe it is a 
> solution for you.
> You can deligate your jobs out of zope and get it back after some time.
> zamqp then fire an event and you subscribe this event to handle thie 
> results.
> 
> with kind regards
> Maik Derstappen
> 
maik,
this looks interesting.
just out of curiosity: how would one alert the user that a long running job (say
after some 10 minutes) has finished.
does the client have to poll?
or is there some "magic" push functionality?

robert