On 30 March 2016, the DCAT Application Profile for data portals in Europe (DCAT-AP) published eight technical implementation guidelines. The guidelines are based on contributions from implementers, who shared their experiences with implementing the DCAT-AP including challenges that they faced and possible solutions and work-arounds.
Background
The work on creating implementation guidelines for the DCAT-AP took place in the context of the work on core vocabularies supported by the European Commission’s ISA programme.
DCAT-AP is a specification based on the Data Catalogue vocabulary (DCAT) for describing public sector datasets in Europe. It provides a common specification for describing public sector datasets in Europe to enable the exchange of descriptions of datasets among data portals. The specification is a joint initiative of DG CONNECT, the EU Publications Office and the ISA Programme. A first version was developed in 2013 and a revision was published in November 2015.
The approach
The overall approach is based on the ISA process and methodology for developing semantic agreements.
In summary, the process and methodology incudes several steps:
- Invitation to members of the working group that was involved in the revision of DCAT-AP to establish the working group for this activity
- Classification of issues brought up by participants
- Selection of priority issues
- Interviews with representatives from major portals and activities on the European level and in the member states and EFTA countries. Interviews were held with the European Data Portal, the European Union Data Portal, Italy, Sweden, Belgium, Norway, Netherlands and Switzerland, while Spain provided answers by e-mail.
- Proposal of a set of guidelines and discussions in the working group via two online meetings (1st meeting, 2nd meeting)
- Review by the working group of the final draft of the guidelines
- Publication of the guidelines
The DCAT-AP implementation guidelines
Based on the priority issues selected by the Working Group, eight technical implementation guidelines were developed and published on Joinup. Moreover, a webpage was created where DCAT-AP implementers can share their tools.
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How to use the MDR data themes vocabulary? |
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How to model and express provenance? |
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How to model Dataset series? Refer to https://joinup.ec.europa.eu/release/dcat-ap-how-model-dataset-series |
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How to refer to licence documents and licence URIs? Refer to https://joinup.ec.europa.eu/release/dcat-ap-how-refer-licence-documents-and-licence-uris |
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How to use identifiers for datasets and distributions? |
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How to extend DCAT-AP? |
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How to describe contact information? |
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How to manage duplicates? Refer to https://joinup.ec.europa.eu/release/dcat-ap-how-manage-duplicates |
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Overview of tools |
Future work
During the activity that led to the guidelines, several issues were raised that could not be further developed.
A main issue that was raised and incited a lot of discussion without reaching a conclusion was the way that data can be accessed through services rather than as a fixed file. The discussion is captured at: https://joinup.ec.europa.eu/node/149728/.
This and other technical issues may be the subject of future activities to further develop guidelines for DCAT-AP or to revise the DCAT-AP specification. These issues relate to, among others,
- The description of different types of Distributions (files, APIs and nested formats);
- Multilingual keywords;
- Data versioning;
- Extended examples of how to use DCAT-AP; and
- Adopting a different method for referring to licence types instead of the ADMS Licence Type Vocabulary, such as the approach of the European Data Portal.
Besides these technical issues, the following organisational problems which could be the subject of future work were identified:
- Referring to the DCAT-AP in public procurement; and
- Further develop business cases for Linked Data.