Overview
CEN ISO/TS 19139-1:2019 (ISO/TS 19139-1:2019) defines XML schema implementation and encoding rules for conceptual UML schemas that describe geographic resources and metadata. It provides a consistent, rule‑based method to derive XML Schema (XSD) representations from UML models used across ISO/TC 211 geographic information standards. These encoding rules are intended for metadata and related conceptual schemas-not for encoding feature application schemas (see ISO 19136 for feature/GML rules).
Key Topics
- Encoding rules for UML → XML Schema: Guidance for converting UML classes, attributes and relationships into XML Schema constructs to ensure interoperable metadata encodings.
- Core XML constructs: Definitions and patterns such as XML Class Type (XCT), XML Class Global Element (XCGE), and XML Class Property Type (XCPT).
- Inheritance & polymorphism: Rules to represent abstract classes, subclasses and polymorphic relationships in XSD.
- Data type encodings: Handling of enumerations, CodeLists, unions and MetaClasses for robust value representations.
- Namespaces and modularity: Strategies for mapping UML packages to XML namespaces, packaging XSDs for reuse, and decoupling implementations across schemas.
- Conformance and testing: Requirements for conformance, quality considerations, and an abstract test suite (annex) to support validation.
- Practical encoding scenarios: Special-case encodings, external implementations, web implementations and backward compatibility considerations.
Applications
This technical specification is practical for anyone implementing or managing geospatial metadata and XML schema implementations:
- GIS software developers creating metadata editors, harvesters, catalogues and exchange formats.
- Data stewards and metadata specialists who need standard XML encodings for ISO 19115‑style metadata.
- Standards bodies and system integrators implementing interoperable metadata across national mapping agencies, INSPIRE-type programs and spatial data infrastructures (SDI).
- Enterprise architects who must model and publish geoinformation metadata as reusable, modular XML schemas.
Using ISO/TS 19139-1 helps organizations produce consistent, validated XML metadata that improve data discovery, exchange and long‑term interoperability.
Related Standards
- ISO 19115 (metadata structure) - metadata content that these encodings represent
- ISO 19136 (GML) - encoding rules for geographic feature application schemas (different scope)
- ISO 19118 - principles for creating encoding rules from UML
- ISO/TS 19115-3 and ISO/TS 19157-2 - examples of metadata standards encoded using these rules
Keywords: ISO/TS 19139-1, XML schema, encoding rules, geographic information, metadata, UML, ISO/TC 211, XML schema implementation, interoperability.