1. Document Validation for PEPPOL Philip Helger Austrian Federal Computing Centre February 11 th 2010 Version 1.0

2. Why validation is important Different countries have different requirements (data formats, middleware, legislation) All business documents are in UBL while within the PEPPOL infrastructure Fail as early as possible

3. Types of validation Technical validation (document structure) – XML Schema – RelaxNG (+ Compact) – … Semantic validation – Schematron – XSLT – CAM (Content Assembly Mechanism) – ….

4. Layered validation Bilateral (Schematron) Industry requirements National requirements Somehow specific (Schematron) CEN Profile specific (Schematron) Basic (Schematron) Technical structure (XSD/RNG) Country independent

5. Transformation and validation workflow Destination country UBL validation PEPPOL tube Full UBL transformation Source format Destination format Transform to destination format Validate incoming UBL Sending entity Receiving entity = Optional/national To be implemented WP8 specified Legend: PEPPOL scope

6. Validation issues Validation is required for each country to check if the national requirements are fulfilled – Maybe national + industry specific validations required Validation is required only for UBL format Version issues – National validation rules may change – The validation itself can have different versions

7. Schematron High level validation language XML based Different versions available – we’re using ISO Schematron Uses XPath for node context determination Differentiates between reports and assertions Result is an SVRL (Schematron Validation Result List) XML document Visit www.schematron.com for detailswww.schematron.com

8. How to apply Schematron Schematron is applied to an XML document – The Schematron itself is transformed to an XSLT script The transformation is done via XSLT The XSLT scripts are provided by schematron.com – Result in an SVRL document Transformation works with Saxon

9. Schematron example BII-T01-003: DocumentType text Must be given for Originator Document Reference BII-T01-004: DocumentType text Must be given for Additional Document Reference BII-T01-006: If Contract ID not specified Contract Type text SHOULD be used for Contract Reference BII-T01-009: A delivery period end date SHOULD be later or equal to a start date BII-T01-026: Price of item must be positive or zero

10. Schematron pitfalls Only reports and assertion  no real error level handling – Use different Schematron rule sets for different error levels Not the full flexibility of XSLT – The Schematron is the one provided by PEPPOL but you are free to apply additional validation rules in your solution

11. Demo Live Demo on Schematron validation

12. Summary Only UBL needs to be validated Technical validation using XSD Semantic validation using ISO Schematron Stacked validation required Test suite to be created Standalone validation service to be provided

13. Q&A Contact me: philip.helger@brz.gv.at Slides will be published Validation tool will be published