The document discusses exchanging metadata between portals using DCAT and DCAT-AP. It provides an overview of the DCAT and DCAT-AP specifications for representing metadata in RDF. DCAT defines a common vocabulary for metadata about data catalogs and datasets, while DCAT-AP profiles DCAT with additional requirements and controlled vocabularies. The document outlines tools and resources for working with DCAT, including specifications, validators, exporters, and vocabularies. It addresses open issues around representing identifiers, roles, and organizations and encourages mapping local vocabularies to common ones to improve interoperability when exchanging metadata.

1. DCAT-AP
Exchanging metadata
OpenBelgium – Antwerp – 2/2016
Bart Hanssens

2. | p. 2
Agenda
 History lessons
 Exchanging metadata
 DCAT / DCAT-AP
 Tools and resources
 Homework
 Questions ?

3. | p. 3
Belgian Constitution (1831), art.32
Everyone has the right to consult
any administrative document
and to obtain a copy,
except in the cases and conditions
stipulated by the laws,
federate laws or rules
referred to in Article 134.

4. | p. 4
Mundaneum (ca.1920)
By fdecomite - Flickr: Drawers, CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=15888697

5. Exchanging metadata
It's not rocket science

6. | p. 6
Everyone loves portals, right ?
 Because there are so many of them …
 Administrations: local / regional / federal / EU …
 Sector / type: biodiversity, geo, statistics, ...
 … powered by different platforms
 CKAN, DKAN, OpenDataSoft, TheDataTank, ...

7. | p. 7
Interoperability
X
Y
Standard
metadata
format
ABC
Z

8. DCAT and DCAT-AP
(Not) reinventing the wheel

9. | p. 9
What is DCAT ?
 “Data CATalog”
 Metadata (only)
 Title, language, description…
 Based on earliest US / UK / NZ … open data portals
 International specification
 Originally (2010) developed by DERI university
 Now maintained by W3C
 It is NOT an API / data format / silver bullet

10. | p. 10
Reuses existing specifications
 RDF vocabulary
 Cool => linked open metadata !
 Reuses other well-known RDF vocabularies
 Dublin Core metadata, FOAF, SKOS
 vCard in RDF
 (SDMX, ADMS)

11. | p. 11
DCAT Catalog (~ portal)
Title
Description
Homepage
Geo area
Publisher
…
Dataset
Dataset
Dataset
Distribution
Distribution
Distribution
Distribution

12. | p. 12
DCAT Dataset
Title
Description
Keyword(s)
Theme(s)
Language(s)
Contact
…
Catalog
Distribution
Distribution

13. | p. 13
DCAT Distribution (~download)
Title
Description
Created, Modified
Download URL
License, Rights
Format
…
Catalog Dataset

14. | p. 14
What is DCAT-AP ?
 DCAT “Application Profile”
 Stricter than DCAT
 Mandatory / recommended properties
 Maintained by (mainly) EU experts on JoinUp
 Optional status, language on Distribution
 Controlled lists / vocabularies
 Categories, languages, file types, geonames …

15. | p. 15
DCAT-AP: languages in Distribution
Dataset
- “Title”@nl
- “Title”@fr
...
Distribution
- “Title”@nl
- DownloadURL
Distribution
- “Title”@fr
- DownloadURL
- MediaType

16. | p. 16
More profiles / extensions ...
 GeoDCAT-AP
 Does not replace (EU Directive) INSPIRE metadata !
 A lot of structured metadata already available
 Mapping + XSLT conversion tool
 StatDCAT-AP
 Eurostat, IMF, OECD... use SDMX format for statistics
 Mapping + conversion tool to be developed

17. | p. 17
A note on GeoDCAT-AP
 Covers ISO 19115 core + INSPIRE metadata
 Mapping AGROVOC / GEMET / INSPIRE themes
 XSLT script
 Converts ISO 19139 XML metadata to GeoDCAT-AP
 Open source CSW API (experimental)

18. Homework
Left as an exercise for the pusblisher

19. | p. 19
Your categories or mine ?

20. | p. 20
Interoperability (again)
X
Y
Well-known
taxonomy
ABC
Z

21. | p. 21
Map and publish !
 No need to give up your own taxonomies
 Map your keywords/categories to known vocabularies
 SKOS is your friend
 RDF vocabulary for controlled lists, taxonomies ...
 “Simple”: exactMatch, closeMatch, altLabel...
 Publish mappings as open data
 Taxonomies for update frequency, location...
 dcterms:accrualPeriodicity, dcterms:spatial
 dcat:mediaType

22. | p. 22
Missing in action / work in progress
 Identifiers for (republished) datasets …
 E.g. “harvested” metadata, plain old websites...
 Roles
 “creator”, “publisher”, “portal harvester” … ?
 URIs for organisations
 Companies, administrations… and smaller units

23. Tools and resources

24. | p. 24
Specifications
 W3C DCAT
 https://www.w3.org/TR/vocab-dcat/
 DCAT-AP
 https://joinup.ec.europa.eu/asset/dcat_application_profil
e/description
 Geo / Stat DCAT-AP
 https://joinup.ec.europa.eu/asset/dcat_application_prof
ile/asset_release/geodcat-ap-v10
 https://joinup.ec.europa.eu/asset/stat_dcat_application_p
rofile/description

25. | p. 25
Tools
 CKAN DCAT extension
 https://github.com/ckan/ckanext-dcat
 Replaces “old” RDF templates in CKAN 2.5
 DCAT validators
 https://validator.dcat-editor.com/
 https://github.com/oSoc15/dcat-validator
 Drupal Experimental DCAT export
 https://www.drupal.org/project/sdcate
 DCAT-AP editor
 https://dcat-editor.com

26. | p. 26
Other
 DCAT “fan page”
 http://dcat.be
 EU Publication Office vocabularies
 http://publications.europa.eu/mdr/authority/
 Data.gov.be DCAT dumps / mappings etc
 https://github.com/fedict/dcattools

27. Questions ?

28. Thanks !
Bart Hanssens / Fedict
Simon Bolivarlaan 30
1000 Brussels, Belgium
@BartHanssens
bart.hanssens [at] fedict.be | www.fedict.belgium.be