[Zope] Re: login page problem

[Dieter Maurer]

Chris Withers wrote at 2005-4-7 13:33 +0100:
>>>>exUserFolder has built in caching (positive and negative caches),
>>>
>>>Dunno what that means, but SUF supports caching via standard 
>>>RAMCacheManagers
>> 
>> That sounds very strange: user objects cached in a RAMCacheManager...
>
>Why? How does that memory-based cache differ in concept from the one 
>inside XUF? ;-)

The RAMCacheManager is associated with (what I call) site building
objects (those have an identifying URL, for example).
"User" objects are not site building.

The UserFolder is but usual implementations do not inherit
"ZCachable" -- and therefore cannot (directly) use the
RAMCacheManager.

When an object supports transparent caching (which would be necessry
for a UserFolder), then it must contain code interfacing with
a cache manager. I doubt that SUF contains such code...

>>>or ZSQL method caching.
>> They cannot be controlled (therefore, I developped "CCSQLMethods"),
> ...
>Sorry, not enough info to be a useful comment. I think this boils down 
>to "CCSQLMethods have better caching that ZSQL Methods", in which case, 
>great, use CCSQLMethods instead

But hopefully you see that the questions are difficult for a standard user.

  When he uses SUF and determines that caching is needed because
  authentication and authorization are too costly, he may learn
  that Z SQL Methods can be cached.
  Later, he changes some user properties and has to observe
  that they take effect with a delay (as stale values are cached)
  and there is no reliable way to flush/invalidate the cache.
  He may learn that there are CCZSQLMethods the cache of which
  can be flushed, but he may have had long hours of problems.

With "exUserFolder", he visits the configuration tab
and selects "with caching for XXX minutes" -- that's
it (unless he uses ZEO).

Thus, if someone needs caching, then "exUserFolder" is easier
then SUF.

> ...
>I'm happy to send you the latest SUF if you're interesteed :-)

The software is built. "exUserFolder" does its job.
No reason to switch at this time...

-- 
Dieter