[Zope] Re: Non-caching version of POPMail ?

[David Shaw]

I actually solved this on my working version in a different way.  I simply
call UIDL on a refresh and if any of the UIDs I have are not in the UID list
from the server, I delete the message from the MessageDict.  It accomplishes
the same thing without the large performance hit of not caching.

I've started working on this product again.  I'd be happy to send you my
current working revision if you want to take a look.  It's not anything
significant enough yet to warrant a new release, but I am making it better.
My next adventure is to do better message parsing to make URLs and email
addresses clickable.  I just got the O'Reilly Regular Expression book and
plan on delving into it when I get a chance.


Loren Stafford said:

> David,
> 
> I'm planning to modify POPMail (or more likely, make a derived product
> POPMailNc) so that there is no persistent message cache. I just wanted to
> pass the idea by you, so you could tell me if I'm doing something stupid or
> if you've already solved my problem for me in a newer version of POPMail.
> 
> I'm using POPMail to couple my Zope server to another product
> (PerfectTracker). Zope initiates Tracker incidents via sendmail and receives
> responses from the Tracker at a dedicated POP3 mailbox, which it polls
> (using Xron) every 5-10 minutes. I've discovered that if I ever delete
> messages from the mailbox manually (i.e. using a POP client other than
> POPMail) POPMail's persistent message cache gets hopelessly out of sync with
> the mailbox, and it begins to deliver messages from its cache when there are
> new messages with the same UID in the mailbox. That's bad.
> 
> While I don't need to delete messages behind POPMail's back, I can't really
> prevent someone from doing so, due to the nature of our mail system. So I
> propose to make POPMail's cache non-persistent (I guess it really wouldn't
> be a cache then, would it?). I don't expect a performance problem, because,
> if I delete old messages regularly I will never have more than a few hundred
> messages in the mailbox. (Messages correspond to new employees.)
> 
> I think I can make uidDict and MessageDict nonpersistent simply by changing
> their names to _v_uidDict and _v_MessasgeDict. Is that correct?
> 
> -- Thanks for your input
> -- Loren
> 

-- 
David Shaw -- Senior Software Developer -- ZapMedia -- 678.420.2715