SchXslt is copyright (c) by David Maus <[email protected]> and released under the terms of the MIT license.

SchXslt is a Schematron processor implemented entirely in XSLT. It transforms a Schematron schema document into an XSLT stylesheet that you apply to the document(s) to be validated.

As of date SchXslt does not properly implement the scoping rules of pattern (see #135) and phase variables (see #136).

Schema, pattern, and phase variables are all implemented as global XSLT variables. As a consequence the name of a schema, pattern, or phase variable must be unique in the entire schema.

Due to the constrains of XSLT 1.0 and the way rules are implemented it is not possible to use a variable inside a rule context expression of a Schematron using the XSLT 1.0 query binding (see #138).

When an external construct is incorporated with sch:include or sch:extends by its @xml:id attribute, the namespace bindings of the include target document are not preserved (#343 #344).

The svrl:active-patterns/@documents attribute does not contain the URIs of the subordinate documents (#342).

SchXslt implements the following Schematron enhancements:

Proposal 1

The Schematron specification does not allow for annotating variables with the expected type of its value. Type annotations are helpful to make the most of XSLT 3.0. Using them is current best practice.

This proposal adds support for an @as attribute on variable declarations.

Proposal 3

The Schematron specification limits the the reuse of abstract rules to the current pattern element. The @href attribute on extends was introduced in 2016 to overcome this limitation but requires a schema author to externalize abstract rules for them to be used.

This proposal extends Schematron with a top-level rules element to hold abstract rules that are globally referencable by the @rule attribute of extends.

Proposal 4

The Schematron specification allows the XSLT elements function and key to be used in a Schematron schema. This makes sense because both are required to set up the query language environment. The key element prepares data structures for the key() function and the function element allows the use of user defined functions.

This proposal adds support for the following XSLT elements:

• xsl:accumulator (XSLT 3.0)
• xsl:import (XSLT 1.0, XSLT 2.0, XSLT 3.0)
• xsl:import-schema (XSLT 2.0, XSLT 3.0)
• xsl:include (XSLT 1.0, XSLT 2.0, XSLT 3.0)
• xsl:use-package (XSLT 3.0)

Depending on your environment there are several ways to install SchXslt.

• Starting with version 1.5 every release on this repository's release page provides a ZIP file with just the XSLT stylesheets. This page also provides a ZIP file with the XSLT stylesheets and two XProc 1.0 steps. Just download and unzip.

• A Java package is published to Maven Central. Use it with Maven or the Java dependency management tool of your choice.

• If you use BaseX or eXist you can download installable XQuery modulesq from this repository's release page as well.

SchXslt uses the Maven build tool to create installable packages. To create the packages for yourself clone this repository, install Maven and run it with the package phase.

dmaus@carbon ~ % git clone --recursive https://github.com/schxslt/schxslt.git
Cloning into 'schxslt'...
remote: Enumerating objects: 450, done.
remote: Counting objects: 100% (450/450), done.
remote: Compressing objects: 100% (298/298), done.
remote: Total 3789 (delta 172), reused 374 (delta 111), pack-reused 3339
Receiving objects: 100% (3789/3789), 470.87 KiB | 1.05 MiB/s, done.
Resolving deltas: 100% (1607/1607), done.

dmaus@carbon ~ % mvn package

This runs the unit tests and creates the following files:

• ant/target/ant-schxslt-{VERSION}.jar (Java archive)
• cli/target/schxslt-cli.jar (Java archive)
• core/target/schxslt-{VERSION}.jar (Java archive)
• core/target/schxslt-{VERSION}-xslt-only.zip (ZIP file with stylesheets)
• exist/target/schxslt-exist-{VERSION}.xar (XQuery package for eXist)
• basex/target/schxslt-basex-{VERSION}.xar (XQuery package for BaseX)

Where {VERSION} is replaced with the current SchXslt version.

The simplest way to use SchXslt is to download the ZIP file with just the stylesheets from the releases page. To validate documents with your Schematron you first transform it with the pipeline-for-svrl.xsl stylesheet. This creates the XSL transformation that creates a validation report when applied to a document.

To use SchXslt in your Java application define the following Maven dependency:

<dependency>
  <groupId>name.dmaus.schxslt</groupId>
  <artifactId>schxslt</artifactId>
  <version>{VERSION}</version>
</dependency>

Where {VERSION} is replaced with the current SchXslt version.

Also take a look at SchXslt Java, a set of Java classes for Schematron validation with SchXslt.

The XQuery module provides a function schxslt:validate() that validates a document and returns a validation report expressed in the Schematron Validation Report Language (SVRL). You import the module using its namespace URI.

import module namespace schxslt = "https://doi.org/10.5281/zenodo.1495494";

let $document := <ex:example xmlns:ex="https://example.com/ns"/>
let $schema :=
  <sch:schema xmlns:sch="http://purl.oclc.org/dsdl/schematron" queryBinding="xslt2">
    <sch:pattern>
      <sch:rule context="/">
        <sch:assert test="true()">Always true</sch:assert>
      </sch:rule>
    </sch:pattern>
  </sch:schema>

return
  schxslt:validate($document, $schema)

The Ant module implements a task for Apache Ant that performs Schematron validation with SchXslt. Download or compile the Jar file and define a new task using name.dmaus.schxslt.ant.Task as class name.

<project name="Test" basedir="." default="build">
  <taskdef name="schematron" classname="name.dmaus.schxslt.ant.Task" classpath="/path/to/ant-schxslt-{VERSION}.jar"/>
  <target name="build">
    <schematron schema="schema.sch" file="document.xml" report="report.xml" phase="myPhase"/>
  </target>
</project>

The task supports the following options:

SchXslt Ant uses XML Resolver to support XML Catalog resolvers.

The CLI module provides a command line program for performing Schematron validation with SchXslt. Download or compile the Jar file schxslt-cli.jar.

To validate the XML document document.xml against the schema in schema.sch with the report written to report.xml you can run:

java -jar schxslt-cli.jar -d document.xml -s schema.sch -o report.xml

The command line option -h lists all available options.

SchXslt CLI v1.10
usage: name.dmaus.schxslt.cli.Application [-d <arg>] [-e <arg>] [-o <arg>]
       [-p <arg>] [-r] -s <arg> [-v]
 -d,--document <arg>     Path to document
 -e,--exitcode <arg>     Use exit code to indicate invalid document
                         (default is 0)
 -o,--output <arg>       Output file (SVRL report)
 -p,--phase <arg>        Validation phase
 -r,--repl               Run as REPL
 -s,--schematron <arg>   Path to schema
 -v,--verbose            Verbose output