GML 2.1.2 Validation

The GML 2.1.2 test engine supports the validation of GML 2.1.2 schemas and instance documents. There is currently one test suite version for Geography Markup Language validation available online via the Legacy CITE Engine. As a stand-alone tool, it is not currently associated with any type of official compliance certification.

Schema Validation

The GML application schema validator checks that the schema is valid according to the XML Schema 1.0 rules and the GML 2.1.2 rules. The schema must be available on a web server via a HTTP URL.

The following checks are performed.

  • XML Schema 1.0 Validity (Users Xerces schema validator).
  • All feature type definitions must extend xmlns(gml=http://www.opengis.net/gml)AbstractFeatureType or from a complex type that extends that type.
  • A GML feature definition must not have a direct child element that derives from xmlns(gml=http://www.opengis.net/gml)gml:AbstractFeatureType.
  • A GML feature definition must not have a direct child element that derives from xmlns(gml=http://www.opengis.net/gml)gml:AbstractGeometryType.

Note: The schemas must define the schemaLocation for all import and include statements that is resolvable from the source schema URL.

Instance Validation

The instance document validation validates a GML instance document against the GML 2.1.2 schemas in the test engine and the application schemas defined in the document. The test document can either be available on a web server via a HTTP url or the body can be pasted into the form.

The following checks are performed.

  • The document must be a valid document and must validate against the application schema defined in the schema location (Users Xerces xml validator).
  • The GML elements must validate against the internal GML 2.1.2 schemas used by the test engine.