i need validate xml dynamic attribute names, data-*. i'am using relaxng schema, not supports dynamic attribute names. options? cannot find relevant..
example of xml:
<?xml version="1.0" encoding="utf-8"?> <body xml:lang="cs" ns="www.x.y"> <h id="x" ctime="2017-09">heading..</h> <desc kw="kw">desc..</desc> <section> <h data-foo="bar" id="one" short="one">first heading</h> <desc>desc...</desc> <p>content..</p> <ul data-buz="fuz"> <li data-switch="click">list item</li> <li>list item 2</li> </ul> </section> </body>
preprocess xml drop data-* attributes before giving validation function. there otherwise no way know validate relaxng or other grammar-based schema languages.
as far preprocessing xml, 1 way existing xml toolchain be: run through xslt transformation drops data-* attributes passes on else as-is:
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/xsl/transform" version='1.0'> <xsl:output method="xml" indent="no"/> <xsl:template match="node() | @*"> <xsl:copy> <xsl:apply-templates select="@* | node()"/> </xsl:copy> </xsl:template> <xsl:template match="@*[starts-with(name(), 'data-')]"/> </xsl:stylesheet> the <xsl:template match="@*[starts-with(name(), 'data-')]"/> important part there. causes data-* attribute dropped on floor. rest of xsl stylesheet basic “identify transform” passes on else source xml as-is.
the w3c nu html checker (html5 validator) backend data-* attributes that’s functionally same xslt transformation, written in java. if you’re curious, code within the github repo w3c nu html checker sources, here:
https://github.com/validator/validator/tree/master/src/nu/validator/xml/dataattributes
see the filterattributes code in dataattributedroppingcontenthandlerwrapper.java
it’s sax filter works @ parse time off parse events prior validation function.
and if you’re more curious, there code other preprocessing filters doing similar things:
nu.validator.xml.customelements.namespacechangingcontenthandlerwrapper—filters out custom elements putting them in special namespace the accompanying relaxng grammar allows elements occur anywherenu.validator.xml.templateelement.templateelementdroppingcontenthandlerwrapper—filters outtemplateelement subtrees—essentially dropping them on floor, because html spec allowstemplatesubtrees contain anything; there’s no need have validation function checking ontemplatesubtrees @ all
anyway, general idea: if there cases of markup constructs in source can’t express validation logic in relaxng or xsd, filter (preprocess) source hide markup validation function.
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