[Zope-dev] zc.async: cron replacement?

[Gary Poster]

On Jun 24, 2009, at 1:19 PM, Reinout van Rees wrote:

> Hi all,
>
> In messages like http://www.mail-archive.com/zope3-dev@zope.org/msg05964.html 
> ,
> zc.async is mentioned as the solution for cron-like functionality in  
> zope.
> Effectively you would not need zope2's clockserver.
>
> Reading zc.async's docs, I cannot find how to do a given task  
> regularly.  For
> example a weekly pack.  Or a daily call of one method that archives  
> older
> items.  That sort of stuff. Many things can be handled by cronjobs,  
> but you
> tend to get a lot of them.  And you don't want to embed the password
> everywhere.
>
> Anyway: I cannot find the word "cron" anywhere in the zc.async  
> source.  Or
> "repetitive" or "regular".  Is zc.async not intended for this kind  
> of usage?

Hi Reinout.

zc.async can be used to do cron-like activities by starting a job, to  
be performed after a certain time, that has a callback that  
reschedules another job when desired.

This has the advantage over cron-like behavior because it does not  
reschedule until the first job is done.

Other zc.async competitors have cron implemented more directly, but I  
found it to be very easy and flexible to do what I wanted using the  
zc.async approach.

Gary