Namespaces

The namespace for GeoDCAT-AP is: http://data.europa.eu/930/

The suggested namespace prefix is: geodcat

The Application Profile reuses terms from various existing specifications, following established best practices [[?DWBP]]. The following table indicates the full list of corresponding namespaces used in this document.

Application Profile Overview

This Application Profile extends [[DCAT-AP-20200608]] by including

• additional classes and properties (marked with a prepended “plus” sign (+) in this document, and summarised in );
• additional recommendations on the use of classes and properties (documented in and );
• additional controlled vocabularies (documented in , along with the ones used in [[DCAT-AP-20200608]]).

These extensions are meant to provide a DCAT-AP-conformant representation of geospatial metadata, identified by defining RDF syntax mappings covering the union of the elements in the INSPIRE metadata schema [[INSPIRE-MD-REG]] [[INSPIRE-MD]] and the core profile of [[ISO-19115]], following the criteria illustrated in .

The current specification does not change the set of geospatial metadata elements already covered in its previous version [[GeoDCAT-AP-20160802]], but rather it updates some of the corresponding mappings based on the new classes and properties included in [[DCAT-AP-20200608]], following the release of version 2 of the W3C Data Catalog (DCAT) Vocabulary [[VOCAB-DCAT-2]], and aligns them with version 2.0.1 of the INSPIRE Metadata Technical Guidelines [[INSPIRE-MD-20170302]]. With the same objective, new terms have been defined in the GeoDCAT-AP namespace for the specification of agent roles (see ) and spatial resolution (see ). As a result, some of the classes and properties defined in [[GeoDCAT-AP-20160802]] have been deprecated and replaced by the equivalent ones in [[DCAT-AP-20200608]] and by the newly defined terms.

The list of deprecated classes and properties is summarised in .

shows a UML diagram of the classes and properties included in the Application Profile.

Mandatory Classes

Recommended Classes

Optional Classes

Deprecated Classes

+Activity

The use of this class in GeoDCAT-AP is illustrated in .

+Address (Agent)

+Address (Kind)

Agent

+Attribution

The use of this class in GeoDCAT-AP is illustrated in .

Catalogue

Catalogue Record

Category

Category Scheme

Checksum

Data Service

Dataset

Distribution

Document

Identifier

Kind

Licence Document

Location

Media Type

+Metric

Period of Time

Provenance Statement

+Quality Measurement

Relationship

Rights Statement

Standard

Requirements for controlled vocabularies

The following is a list of requirements that were identified for the controlled vocabularies to be recommended in this Application Profile.

Controlled vocabularies SHOULD:

• Be published under an open licence.
• Be operated and/or maintained by an institution of the European Union, by a recognised standards organisation or another trusted organisation.
• Be properly documented.
• Have labels in multiple languages, ideally in all official languages of the European Union.
• Contain a relatively small number of terms (e.g. 10-25) that are general enough to enable a wide range of resources to be classified.
• Have terms that are identified by URIs with each URI resolving to documentation about the term.
• Have associated persistence and versioning policies.

These criteria do not intend to define a set of requirements for controlled vocabularies in general; they are only intended to be used for the selection of the controlled vocabularies that are proposed for this Application Profile.

Controlled vocabularies to be used

In the table below, a number of properties are listed with controlled vocabularies that MUST be used for the listed properties. The declaration of the following controlled vocabularies as mandatory ensures a minimum level of interoperability.

Compared with [[DCAT-AP-20200608]], GeoDCAT-AP makes use of additional controlled vocabularies mandated by [[INSPIRE-MD-REG]], and operated by the INSPIRE Registry - with the only exceptions of the coordinate reference systems register maintained by OGC [[OGC-EPSG]].

For two of these controlled vocabularies, namely the INSPIRE spatial data themes [[INSPIRE-THEMES]] and the ISO topic categories [[INSPIRE-TC]], the GeoDCAT-AP Working Group has defined a set of harmonised mappings to the EU Vocabularies Data Themes [[EUV-THEMES]], in order to facilitate the identification of the relevant theme in [[EUV-THEMES]] for geospatial metadata. The status of this work, along with links to a machine readable representation of the mappings, is documented on a dedicated page in Joinup [[?GeoDCAT-ACV]].

Other controlled vocabularies

In addition to the proposed common vocabularies in , which are mandatory to ensure minimal interoperability, implementers are encouraged to publish and to use further region or domain-specific vocabularies that are available online. While those may not be recognised by general implementations of the Application Profile, they may serve to increase interoperability across applications in the same region or domain. Examples are the full set of concepts in EuroVoc [[?EUV-EUROVOC]], the CERIF standard vocabularies [[?CERIF-VOCS]], the Dewey Decimal Classification [[?DDC]] and numerous other schemes.

For geospatial metadata, the working group has identified the following additional vocabularies:

• Geographic identifiers:

  • For marine regions:

    • Marine Regions http://www.marineregions.org/

    • SeaVoX salt and fresh water body gazetteer - https://www.bodc.ac.uk/data/codes_and_formats/seavox/

  • General:

    • DBpedia for Geographic Placenames - http://dbpedia.org/about

    • National gazetteer vocabularies where feasible

    • SeaVoX salt and fresh water body gazetteer for ‘marine geonames’ - https://www.bodc.ac.uk/data/codes_and_formats/seavox/

• Keywords (with controlled vocabularies):

  • For discipline: suggested vocabularies are

    • GEneral Multilingual Environmental Thesaurus (GEMET) - https://www.eionet.europa.eu/gemet/

  • General:

    • GEOSS Societal Benefit Areas - https://en.wikipedia.org/wiki/Societal_Benefit_Areas

    • GEneral Multilingual Environmental Thesaurus (GEMET) - https://www.eionet.europa.eu/gemet/

    • British Oceanographic Data centre - http://www.bodc.ac.uk/

Licence vocabularies

Concerning licence vocabularies, implementers are encouraged to use widely recognised licences such as Creative Commons licences [[?CC]], and in particular the CC Zero Public Domain Dedication [[?CC0]] or CC-BY Attribution 4.0 International [[?CC-BY]], or the Open Data Commons Public Domain Dedication and License (PDDL) [[?PDDL]]. Often there is applicable legislation or a licency policy in place which determine the set of licences to be used. They may recommend the use of an open government licence such as the UK Open Government Licence [[?UKOGL]].

Further activities in this area are undertaken by the Open Data Institute [[?ODI]] with the Open Data Rights Statement Vocabulary [[?ODRS]] and by the Open Digital Rights Language (ODRL) Initiative [[VOCAB-ODRL]].

Provider requirements

In order to conform to this Application Profile, an application that provides metadata MUST:

• Provide a description of the Catalogue, including at least the mandatory properties specified in .
• Provide information for the mandatory properties specified in , if descriptions of Catalogue Records are provided – please note that the provision of descriptions of Catalogue Records is optional.
• Provide descriptions of Datasets in the Catalogue, including at least the mandatory properties specified in .
• Provide descriptions of Distributions, if any, of Datasets in the Catalogue, including at least the mandatory properties specified in .
• Provide descriptions of Data Services, if any, of Datasets in the Catalogue, including at least the mandatory properties specified in .
• Provide descriptions of all organisations involved in the descriptions of Catalogue and Datasets, including at least the mandatory properties specified in .
• Provide descriptions of all category schemes that contain the categories that are asserted in any of the descriptions of Datasets in the Catalogue, including at least the mandatory properties specified in .
• Provide descriptions of all categories involved in the descriptions of Datasets in the Catalogue, including at least the mandatory properties specified in .

For the properties listed in the table in , the associated controlled vocabularies MUST be used. Additional controlled vocabularies MAY be used.

In addition to the mandatory properties, any of the recommended and optional properties defined in MAY be provided.

Recommended and optional classes may have mandatory properties, but those only apply if and when an instance of such a class is present in a description.

Receiver requirements

In order to conform to this Application Profile, an application that receives metadata MUST be able to:

• Process information for all classes specified in .
• Process information for all properties specified in .
• Process information for all controlled vocabularies specified in .

As stated in , "processing" means that receivers must accept incoming data and transparently provide these data to applications and services. It does neither imply nor prescribe what applications and services finally do with the data (parse, convert, store, make searchable, display to users, etc.).