Constraining attr value in DocBook rng schema customization

[dcramer]

Hi there,
I'm trying to create a customization layer for the DocBook 5.0 rng schema in which I constrain the legal values for the security attribute to an enumerated set of values. From tutorials I've read it seems I'm supposed to redefine db.security.attribute as follows:

Code: Select all

    <define name="db.security.attribute">

        <attribute name="security">

            <a:documentation>Security level of this element.</a:documentation>

            <choice>

                <value>internal</value>

                <a:documentation>This element contains internal-only content.</a:documentation>

                <value>reviewer</value>

                <a:documentation>This element contains reviewer-content.</a:documentation>

                <value>external</value>

                <a:documentation>This element contains external content and will be published in all version of the docuemnt.</a:documentation>

                <value>writeronly</value>

                <a:documentation>This element contains writeronly content and will not be published in external, internal, or reviewer versions of the document.</a:documentation>

            </choice>

        </attribute>

   </define>

However, if I add the code above to my customization, Oxygen/Jing complains that <define> for db.security.attribute must have a combine attribute (with a value of interleave or choice). Adding combine="interleave" also gives an error. There's no error if I add combine="choice" but it also doesn't constrain the security attribute and considers the doc valid with any value for security.

How do I completely override a definition from the base schema in my customization layer?

Thanks,
David

[dcramer]

Never mind. I figured out that overrides have to be children of the <include> of the schema you're including and overriding. That makes perfect sense now that I get it...much better than the DTD way.

Sorry for the noise,
David

[george]

Hi David,

No problem, thanks for the follow up. This will be a useful topic for people searching our forum for a similar issue.

Best Regards,
George