[XML-SIG] Using xpath/xslt on proprietary object structures.

[Alexandre Fayolle]

Hello,

>From the description of your situation, I think that using 4SuiteServer
could be a great help. I believe 4SS supports XLink. Depending on the use
you make of XPath, this can be taken care of by the RDF-based indexing
feature of 4XSLT. 

You don't give much details on what your application is made of. However,
if you're using 4DOM, try switching to pDomlette (or even to cDomlette),
which are both more lightweight and faster implementations of DOM (though
not as compliant as 4DOM)

Alexandre Fayolle

On Thu, 20 Sep 2001, Xhaus Main Account wrote:

> Greetings all,
> 
> I'm using python/pyxml/4suite to process a collection of XML files to
> generate a web site (www.paratuberculosis.org), and I'm finding that I
> have problems with memory usage. I have several hundred XML files which
> cross-reference each other, and I have to load them all into memory to
> process them (they are all xlink'ed together)
> 
> I'm thinking that one solution would be to eliminate the use of the DOM,
> and store the information in a hierarchy of python objects which I build
> up myself from the XML files, using SAX.
> 
> I know that it should be possible to achieve this by making my object
> hierarchy present a full DOM interface, i.e. implement the Node,
> Element, Attribute, etc, interfaces.
> 
> However, there would be a large amount of effort involved in
> implementing all of the DOM methods. So I'm looking for possible
> shortcuts, if there are any.
> 
> A few months ago, someone posted on this list (I think it was Eliot
> Kimber) that there were small modifications that could made that would
> make xpath expressions usable against proprietary object
> hierarchies/models. But there was no indication given of how to achieve
> that.
> 
> Has anyone got any pointers as to what those modifications might be, or
> how I would go about implementing such a system.
> 
> Failing that, some pointers to documentation on the architecture of
> 4XPath and 4Xslt would be most useful.
> 
> Thanks in advance for any help rendered.
> 
> BTW, to the authors of the excellent Python XML tools: Please don't take
> any of this as criticism. I continue to be amazed by the flexibility and
> power of Python and available collection of XML processing tools. A huge
> Thank You to all involved in the Python XML effort!
> 
> Regards,
> 
> Alan Kennedy.
> 
> P.S. Out of interest, I have approximately 1335 XML files, taking 2.1meg
> of space. Not all of these files need to processed at the same time,
> although things would be much faster if they could be. I'm finding that
> once the I've loaded in say, 250 members (each of which is represented
> by two or more XML files), and constructed a membership directory XML
> file (listing all of the members), I'm hitting about 130Meg of memory
> usage(!), and my poor little PII-233/160 Meg RAM/NT4 machine starts to
> thrash. I fully realise that my design is not the most efficient, but
> the enormous memory requirements of DOM don't help. Hence why I'm trying
> to find an alternative memory representation foir the documents. I could
> do a total rewrite, but the web site I do for is an unpaid voluntary
> effort, and I can't spare it that much time.
> 
> 
> 
> 
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> 

Alexandre Fayolle
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