[Twisted-Python] Twisted.Persisted ~ ZODB
Kevin Koym
kevin at praxsys.com
Fri Jul 2 09:05:02 EDT 2004
Matt,
I have not integrated the two yet.... (so perhaps my other message was
not appropriate for the list... but I did want to mention the modeling
package as being another direction to look for object persistance.) I am
interested in hearing what others have to say about modeling and twisted
too. I can tell, based on the activity on modeling list, things are
moving on it quicker than was before. I believe that the community
around modeling is starting to grow... so it might have further
usefulness/robustness in the future than it might have in the past.
Thanks,
Kevin
Matt Goodall wrote:
>On Thu, 2004-07-01 at 18:07 -0500, Kevin wrote:
>
>
>>you might also look at http://modeling.sourceforge.net/
>>
>>it is definitely different than other persistance layers in python- but
>>if you have a background similar to mine, it will feel more comfortable
>>to some of these other systems.
>>
>>
>
>I haven't looked at Modeling for a long time. IIRC, it manages database
>connections using its own pool and all interaction takes place within an
>EditingContext. Out of interest, how do you integrate Twisted and
>Modeling? Do you just defer the calls into Modeling to a thread or do
>you have something clever going on?
>
>Thanks, Matt
>
>
>
>>good luck,
>>kevin
>>
>>Jp Calderone wrote:
>>
>>
>>
>>>Eugene Coetzee wrote:
>>>
>>>
>>>
>>>>Hi,
>>>>
>>>>Being new to both Twisted and ZODB and not finding too much info on
>>>>Twisted.Persisted by googling I have decided to post this question.
>>>>
>>>>I have also noticed a few projects running Twisted "on top of" ZODB
>>>>as it were.
>>>>
>>>>I get the impression that Twisted.Persisted is more of an utility
>>>>add-on to Twisted whereas ZODB is a full fledged object database.
>>>>
>>>>
>>> That is true. Nothing in twisted.persisted is usable by itself as a
>>>persistence mechanism for a non-trivial application.
>>>
>>> AOT and Marmalade are graph serialization formats. Neither supports
>>>new-style objects very well, IIRC. Even if they do, neither is
>>>particularly quick, nor provides anything beyond simple storage of a
>>>complete object graph, hardly the only requirement for a database.
>>>
>>> dirdbm is a cute toy, but not again really useful as a non-trivial
>>>data store. It's slow and fragile, and doesn't provide any
>>>functionality beyond what the bsddb module in Python 2.3 provides.
>>>
>>> sob is a handy front-end to AOT, Marmalade, pickle, and tac files.
>>>
>>> crefutil is helper code for aot and jelly and perhaps some other
>>>serialization modules.
>>>
>>> The styles module has all the cool code. It lets you pickle
>>>otherwise unpickleable types and provides the Versioned class, which
>>>lets you deal with mixing old data with new code.
>>>
>>>
>>>
>>>>Still - I would very much like to use Twisted.Persisted for
>>>>trancient data/metadata in a new project I'm tackling cause it is
>>>>always good to minimize dependencies and I know I can use postgreSQL
>>>>with Twisted for heavy duty stuff - which I still believe a better
>>>>option than OODB.
>>>>
>>>>
>>> Unless you have very little data, and you don't care _terribly_ if
>>>you lose it, twisted.persisted probably isn't going to do it for you.
>>>
>>>
>>>
>>>>How does Twisted.Persisted compare to ZODB - if such a comparison
>>>>can be made? Any other OODB's to be considered for use with Twisted?
>>>>
>>>>
>>> You might look at Atop. It's somewhat lighter weight than ZODB.
>>>http://www.divmod.org/ has some docs, but it needs more. It also
>>>isn't distributed separately from Quotient yet (but is easily
>>>separable once you download it).
>>>
>>>
>>>
>>>>I would also very much appreciate some links to on-line docs/examples
>>>>regarding Twisted.Persisted if they exist.
>>>>kind regards,
>>>>
>>>>
>>>>
>>> I wish I could point you at something, but I hope the above has been
>>>an adequate substitute.
>>>
>>> Jp
>>>
>>>_______________________________________________
>>>Twisted-Python mailing list
>>>Twisted-Python at twistedmatrix.com
>>>http://twistedmatrix.com/cgi-bin/mailman/listinfo/twisted-python
>>>
>>>
>>>
>>_______________________________________________
>>Twisted-Python mailing list
>>Twisted-Python at twistedmatrix.com
>>http://twistedmatrix.com/cgi-bin/mailman/listinfo/twisted-python
>>
>>
--
Kevin Koym
Innovation
kevin at praxsys.com
+1.512.698.9328 cell in US
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://twistedmatrix.com/pipermail/twisted-python/attachments/20040702/cf78a423/attachment.htm
More information about the Twisted-Python
mailing list