Assembling Rules in a Schema

You've seen how to write rule and diagnostic elements. Now it's time to assemble these elements in a complete schema.

Schematron Schemas

In brief, rule elements go into pattern elements and diagnostic elements go into diagnostics elements, and all of those are packed within a schema element. For example:

<?xml version="1.0" encoding="UTF-8"?>
<schema xmlns="http://www.ascc.net/xml/schematron">
<pattern name="main">
<rule context="book">
<assert test="@id">Missing "id" attribute.</assert>
<assert test="isbn">Missing "isbn" element.</assert>
<assert test="@id = concat('b', isbn)">The "id" attribute should be
the ISBN number with a prefix "b" </assert>
</rule>
<rule context="*[@id]">
<report test="preceding::*/@id = @id"
diagnostics="idAttribute-en idAttribute-fr "/>
</rule>
</pattern>
<diagnostics>
<diagnostic id="idAttribute-en" xml:lang="en">The id attribute
"<value-of select="@id"/>" is duplicated in element
"<value-of select="name()"/>".</diagnostic>
<diagnostic id="idAttribute-fr" xml:lang="fr">L'attribut id
"<value-of select="@id"/>" de l'élément
"<value-of select="name()"/> est dupliqué".</diagnostic>
</diagnostics>
</schema>

Note

The namespace URI for Schematron 1.5 is http://www.ascc.net/xml/schematron.

The namespace URI for ISO Schematron is http://purl.oclc.org/dsdl/schematron.

What Does This Schema Mean?

This seems intuitive enough, but there are still important questions that need an answer. For instance, in the previous example, book elements obviously ...

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