Fwd: [XML-SIG] xmlpickle.py ?!

M.-A. Lemburg mal@lemburg.com
Tue, 08 Aug 2000 22:52:52 +0200

Jim Fulton wrote:
> "M.-A. Lemburg" wrote:
> >
> > Jim Fulton wrote:
> > >
> (snip)
> > The design doesn't look clear to me, e.g. it seems as if you
> > are first pickling an object using the standard Python pickle
> > mechanism and the pass the pickled string to the XML converter.
> > Is that so ?
> Yes.
> >  ...I think I'd rather like to go the direct way.
> Why? Why is this a goal? By leveraging pickle or cPickle,
> you can let them do alot of heavy lifting, rather than starting
> from scratch. In particular, I'd bet $.05 that cPickle+ppml
> is faster than a "direct" solution.

Probably... speed's currently not imporant for my
application (it will use XML for structure management purposes
rather than actual content storage).

> It *was* a goal for me to work from pickles because it allowed
> me to do database binary<->xml conversion *without* creating
> objects in memory or even having to have the classes around.
> This is handy in alot of cases, for example, for ZODB database
> management and making it easy for humans to read pickles.
> I don't see the harm in separating the pickling and
> xml steps.

That's a valid argument.

My long-term thinking behind this is to
store object information in an XML-aware database or
database front-end and then accessing it via XPath,
so there wouldn't be any conversion to and from pickles.

> > Hmm, I should really try to get the module run outside of
> > Zope... for now I've just been looking at the code.
> It needs to be modified to work with SAX. ppml works with xyap
> which could easily be modified to work with a sax parser.

What is xyap ?
Marc-Andre Lemburg
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