Re: [xml] Inserting XML Schema default attributes

[Daniel Veillard <veillard redhat com>]

On Sun, May 31, 2009 at 03:02:16PM +0200, Stefan Behnel wrote:
> Hi,
>
> as a quick follow-up: injecting default attributes works when applying the
> schema *after* the parsing step, it does *not* work when validating inside
> the parser using the SAX plug.

  Ah, okay, yes I think it makes sense, the SAX plug probably doesn't
expand the attribute list, it's not trivial I guess.

Daniel

> Stefan Behnel wrote:
> > I'm trying to inject default attributes into a document from an XML Schema
> > during parsing. I set up a validation context and set the
> > XML_SCHEMA_VAL_VC_I_CREATE option on it, which, if I understand the docs
> > correctly, tells the validator to create defaulted/fixed attributes if they
> > do not exist already. Then I inject the validation context into the parser
> > using "xmlSchemaSAXPlug()".
> >
> > The schema document I use is
> >
> > '''
> > <xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema";>
> >   <xsd:element name="a" type="AType"/>
> >   <xsd:complexType name="AType">
> >     <xsd:sequence minOccurs="4" maxOccurs="4">
> >       <xsd:element name="b" type="BType" />
> >     </xsd:sequence>
> >   </xsd:complexType>
> >   <xsd:complexType name="BType">
> >     <xsd:attribute name="hardy" type="xsd:string" default="hey" />
> >   </xsd:complexType>
> > </xsd:schema>
> > '''
> >
> > The document I parse is
> >
> > '''
> > <a><b hardy="ho"/><b/><b hardy="ho"/><b/></a>
> > '''
> >
> > The document validates. However, no default attributes are inserted,
> > neither with my code nor with xmllint (which doesn't seem to support that
> > anyway). When I debug into the validator code in xmlschemas.c, I get to
> > line 25351 (libxml2 2.7.3):
> >
> > '''
> >     /*
> >     * Get the owner element; needed for creation of default attributes.
> >     * This fixes bug #341337, reported by David Grohmann.
> >     */
> >     if (vctxt->options & XML_SCHEMA_VAL_VC_I_CREATE) {
> >         xmlSchemaNodeInfoPtr ielem = vctxt->elemInfos[vctxt->depth];
> > ==>     if (ielem && ielem->node && ielem->node->doc)
> >             defAttrOwnerElem = ielem->node;
> >     }
> > '''
> >
> > but "ielem->node" is NULL every time it gets there, so this doesn't fly.
> >
> > Is there anything else I have to do to make this work?
> >
> > Thanks,
> >
> > Stefan
> > _______________________________________________
> > xml mailing list, project page  http://xmlsoft.org/
> > xml gnome org
> > http://mail.gnome.org/mailman/listinfo/xml
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> xml gnome org
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