Schematron Report Customization

Markup UK 2020 Webinars

DOI: 10.5281/zenodo.3890890

Who am I?

David Maus
head of development @ State- and University Library Hamburg
author of SchXslt, a modern XSLT-based Schematron implementation
Contact:
dmaus@dmaus.name https://dmaus.name

This webinar's repository

slides and examples are published at Github github.com/schxslt/schxslt-markupuk2020-webinar
download & extract latest version from the releases page

Repository content

docs/: presentation slides
examples/: examples
schxslt/: schematron implementation (SchXslt 1.4.5)
webinar.xpr: oXygen project file with transformation scenarios for the examples

Report customization use cases

use a less verbose variant of a SVRL report
use a more verbose variant of a SVRL report
use a custom report format
create an annotated document instance

XSLT-based implementations

SchXslt: github.com/schxslt/schxslt
Skeleton: github.com/schematron/schematron
Skeleton variants: modified versions of the Skeleton

Two stages of an XSLT-based implementation

Customize the report by customizing the compiler

Compiler customization

Parts of the validation stylesheet are created by named templates

SchXslt Callback API

schxslt-api:active-pattern	instructions for when a pattern is activated
schxslt-api:fired-rule	instructions for when a rule matches the context node
schxslt-api:shadowed-rule	instructions for when a rule does not match the context node because the node was matched by a previous rule of the same pattern
schxslt-api:failed-assert	instructions for when the expression in the @test attribute of an assertion evaluated to false
schxslt-api:succesful-report	instructions for when the expression in the @test attribute of a report evaluated to true
schxslt-api:validation-stylesheet-body-top-hook	instructions that go to the top of the validation stylesheet
schxslt-api:validation-stylesheet-body-bottom-hook	instructions that go to the bottom of the validation stylesheet
schxslt-api:report	create the final report

Using the callback API

customization via the callback API utilizes the import mechanism of XSLT
if the compiler calls a template, the XSLT processor selects the one with the highest import precedence
to customize the report
1. import the compiler stylesheet
2. override the API templates
3. use your stylesheet to compile the validation stylesheet

Example 1: Built-in compiler for SVRL report

schxslt/2.0/compile-for-svrl.xsl

Example 2: Custom SVRL

examples/example-2

Create a SVRL report but without information about active patterns, fired, and shadowed rules.

Example 3: Custom report

examples/example-3

Use a custom report format.

                            start = element report {
    element failed-assert {
        attribute id { xs:ID }
      & attribute timestamp { xs:datetime }
      & empty
    }*
}

Example 4: Annotated document

examples/example-4

Annotate elements of the document instance.

Limitations

no straightforward way to create a nested report
requires access to the URI of the compiler stylesheet

Schematron Mailinglist: schematronist.org
Slack Channel: xmlcom.slack.com