Schematron for eXist

XQuery library module to use ISO Schematron in eXist. This module uses the standard Schematron implementation from https://code.google.com/p/schematron/. This module is a port of schematron-basex to eXist.

⚠️ This module relies on the "skeleton" Schematron implementation, which is no longer maintained. Please consider using SchXslt instead.

Usage

Install the module in the way described in the eXist documentation. Go to the Dashboard and open the Package Manager. Click the add a package button, and then upload schematron-exist-1.1.xar.

After the module is installed, in your XQuery code declare the module import:

import module namespace schematron = "http://github.com/Schematron/schematron-exist";

Your Schematron schema file first has to be compiled before it can be used to validate XML. The compiled Schematron can be re-used to validate multiple documents, or possibly stored in a collection for later use.

let $sch := schematron:compile(doc('rules.sch'))

If your Schematron contains phases you can specify the phase to use by passing the name of the phase in the second argument.

let $sch := schematron:compile(doc('rules.sch'), 'phase1')

If you need to pass additional parameters to compile the Schematron the second argument can be provided as a parameters element. The phase can be specified by including a parameter named phase.

let $sch := schematron:compile(doc('rules.sch'), <parameters><param name="phase" value="phase1"/></parameters>)

Next, validate an XML using the compiled Schematron.

let $svrl := schematron:validate(doc('document.xml'), $sch)

The validate method returns SVRL XML. This module provides several utility methods for inspecting SVRL.

To simply check whether validation has passed or failed use the is-valid method, which returns a boolean value.

let $boolean := schematron:is-valid($svrl)

Schematron validation may return warnings or informational messages in addition to error messages. The has-messages method returns a boolean value to indicate if any messages are present.

let $boolean := schematron:has-messages($svrl)

To get all messages that were generated as a sequence:

let $messages := schematron:messages($svrl)

The message-level method returns 'error', 'warn' or 'info' (or custom values) based on the role attribute on Schematron <assert> and <report> elements. This method normalizes the role attribute value from the Schematron schema: if the role attribute is absent or contains 'error' or 'fatal' this method returns 'error'; if role contains 'warn' or 'warning' this method returns 'warn'; if role contains 'info' or 'information' this method returns 'info'. Any other value of the role attribute is returned unchanged.

let $level := schematron:message-level($message)

To get the human text description from a message:

let $string := schematron:message-description($message)

To get the XPath location where a message was generated:

let $string := schematron:message-location($message)

Putting this all together:

import module namespace schematron = "http://github.com/Schematron/schematron-exist";

let $sch := schematron:compile(doc('rules.sch'))
let $svrl := schematron:validate(doc('document.xml'), $sch)
return (
  schematron:is-valid($svrl),
  for $message in schematron:messages($svrl)
  return concat(schematron:message-level($message), ': ', schematron:message-description($message))
)

More examples are available in the examples folder.

Using XPath 2.0 and above

XPath 2.0 is supported out of the box. Remember to set attribute queryBinding="xslt2" on the schema element of your Schematron.

Developing

This module was developed using eXist 3.0RC1, although it may work with earlier versions.

Unit tests are located in the test folder. To run the unit tests open test-suite.xq in eXide and then click the Eval button.

The included Ant build script build.xml will create a xar file for loading into eXist.