validator/docs/architecture.md

General Architecture

The validator itself is just an engine which executes validation according to a certain configuration (see configuration documentation).

The validator takes a sceanrio.xml and the configured directory with all artifacts necessary for validation (scenario repository). Then it performs the validation and generates a report in XML format. This report is then the input to an XSLT provided by the configuration.

Separation of concerns

• The purpose of the validator is to only report if an XML instance is valid or not
• A configuration can provide an XSLT which takes the validator report and generates an own report
  • This report may choose to conclude acceptance of the XML instance or not

The validator reports valid/invalid, a configuration reports acceptance/rejection!

General process

The general process is like this:

sequenceDiagram
  participant e as Validator
  participant c as Configuration
  e->>+c: create ScenarioRepository
  c->>-e: is available
  e->>e: parse XML
  e->>e: select scenario
  e->>e: validate XSD
  e->>e: validate Schematron
  e->>e: create Validator Report
  e->>+c: execute configuration report generator
  e->>-c: return XPATH of acceptance message
  

1. XML-Parsing: Is the XML instance valid in the basic sense. If not, validation is stopped and the validator report is returned with status invalid.
2. Identifikation of applicable scenario: The configuration must have a defined scenario which matches the XML instance (it is an XPATH expression). If no scenario matches, validation is stopped and the validator report is returned with status invalid.
3. XML-Schema validation: The XML instance must be valid according to the configured XSD. If not, validation is stopped and the validator report is returned with status invalid.
4. Schematron validation
5. Aggregation of validation results: All results are aggregated into the validation report:
   • In case there is a single error or warning the report will have status erhältinvalid, otherwise the status will be valid.