Re: [xml] Question regarding Xpath and streaming

["Yong Chen \(yongche\)" <chen cisco com>]

On the same note, is there any way to validate a document (against a
schema) which is being streamed out using xmlWriter? 

"xmlSchemaValidateDoc(validCtxtPtr, doc)" needs a "doc", but when doing
streaming, I don't have the full doc available.


Thanks,
Yong Chen

> -----Original Message-----
> From: Daniel Veillard [mailto:veillard redhat com] 
> Sent: Tuesday, June 26, 2007 2:38 AM
> To: Yong Chen (yongche)
> Cc: xml gnome org
> Subject: Re: [xml] Question regarding Xpath and streaming
>
> On Mon, Jun 25, 2007 at 06:24:46PM -0700, Yong Chen (yongche) wrote:
> > Hi,
> >
> > I've a question regarding xpath and streaming (xmlWriter):
> >
> > I use xpath to filter a document so I get selected (or 
> filtered) nodes.
> > I also use xmlWriter to stream output. I wonder if I can use both 
> > together.
> >
> > Libxml xpath works by first getting xmlXpathContextPtr (API:
> > xmlXpathNewContext(doc)), this means the document (doc) has to be 
> > available. But if I'm streaming the data into a file 
> > (xmlNewTextWriterFilename()), I don't have the doc 
> available. So how 
> > can I apply the xpath filtering in xmlWriter streaming?
>
>   Normal XPath operations require a full tree.
>   There is a pattern module allowing to stream for a very 
> small subset of XPath, see 
> http://xmlsoft.org/html/libxml-pattern.html , but I don't 
> have user friendly docs for it.
>
> Daniel
>
> --
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> veillard redhat com  | libxml GNOME XML XSLT toolkit  
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