[Zope] Re: Stepper

[Chris Withers]

Hi Gary,

Gary Poster wrote:
> Hey Chris.  Ever on the lookout for better things to replace our code  
> (e.g., zasync), I took a look at Stepper.  It looks nice and simple  (as 
> per your company name, I suppose ;-).  It's particularly nice  that it 
> looks easier to set up than zasync.

Thanks! :-)

I like things simple, hence the company name and tag line ;-)

> We primarily need zasync for frequent, user-requested async tasks  fired 
> from within a browser.  From poking around in Stepper I thought  maybe 
> one could do that with a cron job kicking stepper and some  other 
> tricks, 

"some other tricks" being something in ZODB that built up a queue for a 
Stepper step to process...

> but it didn't seem that was a primary use case for you,  because 
> I still think zasync would do a better job there.

Indeed, Stepper is for doing "once a day" type stuff. It was originally 
developed to run sets of migration code, but is now going to be used to 
do checking of Link Objects, sending reminders about expired content, 
packing ZODB, etc. That said, I see no reason why it couldn't be used to 
meet your use case...

> To be clear, Stepper does tasks zasync couldn't; 

oh?

> and I think it would  
> be more appropriate for some of our zasync usages in the field,  
> particularly once you beef up the error handling. 

I'm curious about this... what needs beefing up?

> The class design  for 
> defining jobs is certainly prettier than what I did too, though  
> arguably both approaches have advantages.  I might choose your  approach 
> for a new take on zope_exec plugin, for instance, if I did  more zasync 
> work.

Hmmm, what's zope_exec?

> In any case, to your knowledge, am I on the right track with my  
> analysis of what you have done? 

Yup, think so...

> Does Stepper support frequent,  
> browser-requested async tasks, now or in your plans?

Not really, that's not its focus. But, another product could easily be 
built to handle the "put jobs in a queue" thing and also supply a 
Stepper step. Maybe zasync could evolve to do just that and leave the 
actual offline task running (which is an admittedly pretty small task!) 
to Stepper?

> I would have sent this to the zope mailing list if I subscribed; feel  
> free to cc responses there if you would like.

Sure, I'll CC the zope list in for kicks :-)

cheers,

Chris

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