[Zope-dev] Re: AdaptableStorage

[Chris Withers]

seb bacon wrote:
>> I'd prefer just to have a method somewhere that, as Shane suggested, 
>> could be hit by URL, etc.
>>
>> A whole seperate server seems like overkill...
> 
> But what about, for example, databases which don't have an efficient way 
> to do callbacks to external applications?  You may have to do a "SELECT 
> id FROM tblObjects WHERE timestamp > some_time" or a similar kludge from 
> a polling server.  You may want this server to reside at the same 
> location as the RDBMS, rather than as a thread in Zope.

Well, if by server you could mean "script that gets run by cron every 1 minute 
and hits a URL in Zope if something has changed", then I might be in agreement ;-)

> I'm worrying that if we are not to be restricted to Oracle or bleeding 
> edge kernels, the notification part of the cache invalidation scheme may 
> be (a) kludgy, (b) inefficient, and (c) utterly different in design 
> between different storages.

I think this is as "such is life" problem. Provided AdaptableStorage provides 
some way (exposed url?) for an external process to say that things have changed, 
I think that's the best form of flexibility we can provide.

cheers,

Chris