CARVIEW |
This document reports on evidence and implementations of the Data Catalog vocabulary version 3 (DCAT3) Candidate Recommendation [[VOCAB-DCAT-3]]. In particular, it demonstrates that the revisions proposed in [[VOCAB-DCAT-3]] are already in use and are also implementable.
Introduction
DCAT is an RDF vocabulary, first published as a W3C Recommendation in 2014 [[VOCAB-DCAT]], designed to facilitate interoperability between data catalogs published on the Web. The Dataset Exchange Working Group (DXWG) has developed a new version of DCAT [[VOCAB-DCAT-3]], which extends [[VOCAB-DCAT-2]] to support further use cases and requirements [[DCAT-UCR]]. These include the possibility of providing digest for DCAT distributions, the support for resource's versioning and data series.
To show that the revisions proposed in [[VOCAB-DCAT-3]] are implementable and adopted, we collected evidence in the form of vocabularies, data catalogs, data services, and datasets (). The results are summarized in this report.
Methodology
We followed the steps described below to collect evidence for the revisions proposed in [[VOCAB-DCAT-3]]:
- Identify the actual list of revisions proposed in [[VOCAB-DCAT-3]] for which implementation evidence should be collected (see for more details).
- Review some existing vocabularies based on [[VOCAB-DCAT]] or [[VOCAB-DCAT-2]], and identify if they include already the changes proposed in [[VOCAB-DCAT-3]], and/or their alignment with [[VOCAB-DCAT-3]] is planned. The rationale for including also planned implementations is that these vocabularies are not likely to adopt the revisions proposed in [[VOCAB-DCAT-3]] until it becomes a W3C Recommendation.
- Check existing datasets to verify if the changes proposed [[VOCAB-DCAT-3]] are implemented.
- Develop an Implementation Report with details of the steps above.
As noted, to have a broader coverage of [[VOCAB-DCAT-3]] adoption we considered different types of evidence:
- DCAT-based vocabularies
- Existing datasets metadata
This report includes only a representative subset, providing nonetheless enough implementation evidence of the revisions proposed in [[VOCAB-DCAT-3]]. Our perspective only aims to review some of the existing vocabularies to find proof that each feature is implemented at least once.
Meeting the exit criteria
As described in the DXWG charter, to advance to Proposed Recommendation, evidence will be adduced in order to demonstrate that each of the changes made to the original DCAT Recommendation [[VOCAB-DCAT]] has been published and consumed independently in catalogs and related systems at least once, although a higher number is expected for the majority of terms.
Evidence of implementation was gathered from existing datasets, which already implement the proposed changes, as well as from existing application profiles of [[VOCAB-DCAT]].
Summary of proposed revisions
The following table shows the set of changes proposed in [[VOCAB-DCAT-3]].
Implementations
DCAT-based vocabularies and datasets
The following table shows DCAT-based vocabularies providing implementation evidence of the revisions proposed in [[VOCAB-DCAT-3]].
ID | Application Profile/Datasets in Catalog | Creator | Country | Year |
---|---|---|---|---|
V01 | [[DCAT-AP-3]] | SEMIC action, Interoperable Europe, European Commission | Europe | 2024 |
V02 | [[GeoDCAT-AP-2]] | European Commission | Europe | 2020 |
V03 | [[DCAT-EP]] | European Parliament | Europe | 2022 |
V04 | The official portal for European data | European Commission | Europe | 2024 |
The criteria used to select the relevant vocabularies are the following ones:
- They are based on [[VOCAB-DCAT-3]] or they extend [[VOCAB-DCAT]] with properties and classes included in [[VOCAB-DCAT-3]].
- Preferably, they are used across multiple data catalogs and/or domains/disciplines.
The vocabularies listed earlier in this section have been chosen for the following reasons:
- [[DCAT-AP]] is a profile of [[VOCAB-DCAT]] used across Europe since 2014 as a metadata interchange format, primarily for catalogs of government data, and, to some extent, for scientific data. As such, it has a broad geographic coverage, and it is supported in data catalogs (e.g., the European Data Portal) and catalog platforms (e.g., CKAN). This report considers [[DCAT-AP-3]] that is the latest editor's draft release.
- [[DCAT-EP]] is an extension of the DCAT Application Profile for European data portals (DCAT-AP), designed and used for documenting datasets and data services of the European Parliament.
- [[GeoDCAT-AP-2]] is domain-specific extension of [[DCAT-AP]] for geospatial and statistical data, respectively, and they share the same geographic coverage of [[VOCAB-DCAT]].
Furthermore, the [[DataEuropaPortal]] serves as a pivotal hub for accessing European open data across a spectrum of sources, including international, European Union, national, regional, local, and geodata portals. It amalgamates the former EU Open Data Portal and the European Data Portal into a cohesive platform. Datasets available through the portal are considered as proof of implementation for a DCAT 3 features.
[[DCAT-AP]] has also been used as a basis for the development of country-specific extensions (see [[DCAT-AP-EXT]]). Such extensions have not been included in this report, but they provide additional support to the implementation evidence for the revisions proposed in [[VOCAB-DCAT-3]] already included in [[DCAT-AP-3]].
Implementation Evidence
The table below shows the evidence collected for each one of the revisions proposed in [[VOCAB-DCAT-3]], including, for each revision, the existing implementations - flagged with "✔" -, as well as the planned implementations - flagged with "(✔)". The vocabularies and data catalogs/data services/datasets corresponding to columns in this table are listed in subsequent sections.
The reported planned implementations reflect the following (not mutually exclusive) scenarios:
- The vocabulary or the metadata schema of the data catalog is being aligned with [[VOCAB-DCAT-3]] (or this alignment is planned).
- The vocabulary or data catalog supports equivalent or similar properties and classes, that may be eventually replaced by those defined in [[VOCAB-DCAT-3]].
General analysis
Based on the collected evidence, all the revisions proposed in [[VOCAB-DCAT-3]] have at least 1 implementation, considering both the existing and the planned ones.
The corresponding number of implementations for each revision is summarised in .
Acknowledgements
The editors gratefully acknowledge the contributions made to gathering evidence for [[VOCAB-DCAT-3]] and reviewing this report by all members of the working group,