[tei-council] Schematron embedded in RelaxNG

Tue Sep 25 09:23:24 EDT 2012

Yes, that works for me and seems to have the correct error 
messages... don't know why it didn't before.

There is a question here, isn't there... should our default 
oXygen templates have the extra schematron constraint?

-James

On 24/09/12 23:59, Martin Holmes wrote:
> Ah -- James has figured out what I hadn't: that if you associate your
> RNG file with your XML file twice, once as RelaxNG and once as
> Schematron, then it works.
>
> I had no idea that you could do that, and I don't really know how anyone
> else would know either. I thought an xml-model PI with
> schematypens="http://purl.oclc.org/dsdl/schematron" had to point to a
> Schematron file. Perhaps there should be a way for people to find out
> how to do this? I almost never create a new XML document in the way
> James describes; usually I'm taking an existing document and changing
> it, so if my existing documents didn't have that link to the RelaxNG
> schema as Schematron, then my new one wouldn't either, and I'd never
> know anything about Schematron.
>
> To answer your question below, my message (below yours below) has a test
> document which is valid RNG-wise, but violates two simple Schematron
> constraints. That should work to test your system (it does for me).
>
> Cheers,
> Martin
>
> On 12-09-24 06:56 PM, James Cummings wrote:
>>
>> Martin,
>>
>> When I start a new XML document, then manually type in a root
>> node, then associate a schema with it (and check the 'use
>> schematron' checkbox), then correct my TEI until I ahve a valid
>> document... the top looks like this:
>>
>> <?xml version="1.0" encoding="UTF-8"?>
>> <?xml-model
>> href="http://www.tei-c.org/release/xml/tei/custom/schema/relaxng/tei_all.rng"
>> type="application/xml"
>> schematypens="http://purl.oclc.org/dsdl/schematron"?>
>> <?xml-model
>> href="http://www.tei-c.org/release/xml/tei/custom/schema/relaxng/tei_all.rng"
>> type="application/xml"
>> schematypens="http://relaxng.org/ns/structure/1.0"?>
>>
>> i.e. has both a schematron xml-model and a relaxng one.
>>
>> If I do this I get an error if I don't have an <l> inside my <lg>
>> (or a nested <lg>). However, this is just a vague schema based
>> error because it says:
>> "E [Jing] element "lg" incomplete; expected element "addSpan",
>> "alt", "altGrp", "anchor", "argument", "byline", "camera",
>> "caption", "cb", "certainty", "damageSpan", "dateline",
>> "delSpan", "desc", "docAuthor", "docDate", "epigraph", "fLib",
>> "figure", "fs", "fvLib", "fw", "gap", "gb", "head", "incident",
>> "index", "interp", "interpGrp", "join", "joinGrp", "kinesic",
>> "l", "label", "lb", "lg", "link", "linkGrp", "listTranspose",
>> "meeting", "metamark", "milestone", "move", "notatedMusic",
>> "note", "opener", "pause", "pb", "precision", "respons",
>> "salute", "shift", "sound", "space", "span", "spanGrp", "stage",
>> "substJoin", "tech", "timeline", "view", "vocal", "witDetail" or
>> "writing"
>>
>> Although the only thing that makes the error go away is an lg or
>> an l, it isn't a very useful error message.
>>
>> Is there another schematron constraint I can test instead?
>>
>>
>> -James
>>
>> On 24/09/12 17:53, Martin Holmes wrote:
>>> Hi all,
>>>
>>> During the FTF I was talking to Sebastian about the fact that our
>>> Schematron constraints are embedded directly into RelaxNG files; he
>>> believed that this meant that normal validation would cause them to be
>>> triggered, but I couldn't remember having been caught by a Schematron
>>> constraint when validating against a RelaxNG schema, even though I know
>>> I know I've violated them. So I've just started testing this.
>>>
>>> The RelaxNG schema for tei_all:
>>>
>>> <http://www.tei-c.org/release/xml/tei/custom/schema/relaxng/tei_all.rng>
>>>
>>> does indeed contain our handful of existing Schematron rules; if you
>>> look at the element definition for <lg>, you'll see the constraint we
>>> recently added, which says that an <lg> must contain at least one child
>>> <l>, <lg> or <gap>.
>>>
>>> However, when I create a test document violating this constraint and one
>>> of the others, and validate it against this schema in Oxygen 14, nothing
>>> happens. (The test document is below.)
>>>
>>> So I went digging to try to figure out whether it was realistic to
>>> expect Schematron validation as part of RelaxNG validation. According to
>>> the Jing home page, Jing only has "experimental" support for Schematron,
>>> and it's Schematron 1.5, not ISO Schematron. The documentation also says
>>> that "Jing's implementation is not based on the reference Schematron 1.5
>>> implementation. It is implemented partly in XSLT and partly in Java.
>>> This implementation requires that the Schematron elements be properly
>>> namespaced using the namespace URI http://www.ascc.net/xml/schematron."
>>> However, our schema uses the ISO Schematron namespace,
>>> "http://purl.oclc.org/dsdl/schematron". They often do define a prefix
>>> for the old namespace, but they use the new one instead -- as they
>>> should, I think, since we're using ISO Schematron.
>>>
>>> Looking at the other available RelaxNG validators, the only one that
>>> promises the possibility of Schematron support is the Sun MSV validator,
>>> which seems to have disappeared from the web with the Oracle take-over.
>>>
>>> So we don't seem to have a working validation mechanism for Schematron
>>> embedded in RelaxNG schemas, unless I've missed some key configuration
>>> option in Oxygen or at the command line.
>>>
>>> So the next thing I thought I'd do was to generate a Schematron schema
>>> from Roma based on tei_all. I went to the latest and greatest Roma, here:
>>>
>>> <http://tei.oucs.ox.ac.uk/Roma/>
>>>
>>> chose to reduce a schema from the maximum possible schema, and made no
>>> changes. I generated an ISO Schematron schema from that, and got a file
>>> with no constraints in it at all:
>>>
>>> <?xml version="1.0" encoding="utf-8"?>
>>> <schema xmlns="http://purl.oclc.org/dsdl/schematron"
>>>             xmlns:oxdoc="http://www.oxygenxml.com/ns/doc/xsl"
>>>             queryBinding="xslt2">
>>>        <title>ISO Schematron rules</title>
>>>
>>> <!--namespaces:--><!--keys:--><!--patterns:--><!--constraints:--></schema>
>>>
>>> So that doesn't work, for some reason. Instead, I downloaded
>>> tei_all.odd, and ran this:
>>>
>>> roma --isoschematron tei_all.odd .
>>>
>>> to get an ISO Schematron file. Validating my test file against that
>>> produced the expected errors.
>>>
>>> So unless I'm missing something, it's unlikely that most people are
>>> getting any benefit from our Schematron constraints, unless they're
>>> aware that they have to manually generate a schematron schema and link
>>> it into their XML files. If this is the case, I think we should be
>>> documenting this process somewhere.
>>>
>>>
>>> This is my test doc, which violates two of our Schematron constraints:
>>>
>>> <?xml version="1.0" encoding="UTF-8"?>
>>> <?xml-model
>>> href="http://www.tei-c.org/release/xml/tei/custom/schema/relaxng/tei_all.rng"
>>> type="application/xml" schematypens="http://relaxng.org/ns/structure/1.0"?>
>>> <TEI xmlns="http://www.tei-c.org/ns/1.0">
>>>         <teiHeader>
>>>             <fileDesc>
>>>                 <titleStmt>
>>>                     <title>Testing Schematron constraints in RelaxNG</title>
>>>                 </titleStmt>
>>>                 <publicationStmt><p>Public test document</p></publicationStmt>
>>>                 <sourceDesc><p>Born digital</p></sourceDesc>
>>>             </fileDesc>
>>>         </teiHeader>
>>>         <text>
>>>             <body>
>>>                 <div>
>>>                     <lg>
>>>                         <stage>Enter James stage left, looking shifty.</stage>
>>>                         <figure><figDesc>Picture of some lines of
>>> poetry.</figDesc></figure>
>>>                     </lg>
>>>                     <p><ref target="http://www.uvic.ca/"
>>> cRef="UVic">UVic</ref></p>
>>>                 </div>
>>>             </body>
>>>         </text>
>>> </TEI>
>>>
>>> Cheers,
>>> Martin
>>>
>>
>>
>

-- 
Dr James Cummings, researchsupport at it.ox.ac.uk
Research Support, IT Services, University of Oxford