Re: lxml + mod_python: cannot unmarshal code objects in restricted execution mode

Dmitri Fedoruk wrote:
> I'm developing a mod_python application that is based on XML\XSLT
> transforming.
> 
> I used 4Suite libraries for that, but as the speed was unacceptable
> for me, I switched to lxml. Everything became much easier and 10 times
> faster

Thanks for sharing that. :)

> but I've encountered the subject problem.
> 
> In brief - all my data and xslt are stored and transferred in UTF-8.
> With 4Suite everything was fine all the time. With lxml it works fine
>  from the console, but inside mod_python it occasionaly dies, ~ one
> time out of three. Strange - the same code with the same data works or
> dies by its own means.
> 
> As far as I have found, there was a similar problem with PyXML and
> encodings module, this is the problem with UTF, but there was no clear
> solution.
> 
> So, my configuration is the following:
> Python 2.5.1
> Server version: Apache/2.2.4 (FreeBSD)
> mod_python-3.3.1

Looks like you forgot to mention the lxml version you are using.

> And the relevant parts of my code are these:
> 
> def extApplyXslt(xslt, data, logger ):
>     try:
>         strXslt = urllib2.urlopen(xslt).read()
>         # i have to read the xslt url to the python string
>     except urllib2.HTTPError, e:
>        .......
>     except urllib2.URLError, e:
>        .............
>     try:
>         xslt_parser = etree.XMLParser()
>         xslt_parser.resolvers.add( PrefixResolver("XSLT") )
> 
>         # and now I have to use the string; a more elegant solution,

As I already mentioned on c.l.py, you can pass the result of urlopen()
directly into parse().

>         f = StringIO(strXslt)
>         xslt_doc = etree.parse(f, xslt_parser)
> 
>         # and here where the problem comes
>         transform = etree.XSLT(xslt_doc)
> 
>     except Exception, exc:
>         logger.log(logging.CRITICAL, exc.__str__() )
> 
>     try:
>       result_tree = transform(data)
>       return etree.tostring(result_tree, 'utf-8')
>     except Exception, exc:
>       print "xslt processing error!", exc.__str__()
>       return ""
> 
> It dies with the message 'cannot unmarshal code objects in restricted
> execution mode'. By profiling I detected the point where problem
> occurs:
>   transform = etree.XSLT(xslt_doc)

Hmmm, I can't see where any "unmarshaling" should be taking place here -
definitely not in XSLT(). And I don't get why this should only happen once in
a while.

Can you figure out what is writing this message? The python interpreter or
mod_python?

Stefan