Practical Guide to Migrating to DCAT-AP-ES

The future new version of the Technical Standard for Interoperability of Public Sector Information Resources (NTI-RISP) incorporates DCAT-AP-ES as a reference model for the description of data sets and services. This is a key step towards greater interoperability, quality and alignment with European data standards.

This guide aims to help you migrate to this new model. It is aimed at technical managers and managers of public data catalogs who, without advanced experience in semantics or metadata models, need to update their RDF catalog to ensure its compliance with DCAT-AP-ES. In addition, the guidelines in the document are also applicable for migration from other RDF-based metadata models, such as local profiles, DCAT, DCAT-AP or sectoral adaptations, as the fundamental principles and verifications are common. 

Why migrate to DCAT-AP-ES?

Since 2013, the Technical Standard for the Interoperability of Public Sector Information Resources has been the regulatory framework in Spain for the management and openness of public data. In line with the European and Spanish objectives of promoting the data economy, the standard has been updated in order to promote the large-scale exchange of information in distributed and federated environments. 

This update, which at the time of publication of the guide is in the administrative process, incorporates a new metadata model aligned with the most recent European standards: DCAT-AP-ES. These standards facilitate the homogeneous description of the reusable data sets and information resources made available to the public. DCAT-AP-ES adopts the guidelines of the European metadata exchange scheme DCAT-AP (Data Catalog Vocabulary – Aplication Profile), thus promoting interoperability between national and European catalogues. 

The advantages of adopting DCAT-AP-ES can be summarised as follows:

• Semantic and technical interoperability: ensures that different catalogs can understand each other automatically.
• Regulatory alignment: it responds to the new requirements provided for in the NTI-RISP and aligns the catalogue with Directive (EU) 2019/1024 on open data and the re-use of public sector information and Implementing Regulation (EU) 2023/138 establishing a list of specific High Value Datasets or HVD), facilitating the publication of HVDs and associated data services.
• Improved ability to find resources: Makes it easier to find, locate, and reuse datasets using standardized, comprehensive metadata.
• Reduction of incidents in the federation: minimizes errors and conflicts by integrating catalogs from different Administrations, guaranteeing consistency and quality in interoperability processes. 

What has changed in DCAT-AP-ES?

DCAT-AP-ES expands and orders the previous model to make it more interoperable, more legally accurate and more useful for the maintenance and technical reuse of data catalogues. 

The main changes are: 

• In the catalog: It is now possible to link catalogs to each other, record who created them, add a supplementary statement of rights to the license, or describe each entry using records.
• In datasets: New properties are added to comply with regulations on high-value sets, support communication, document provenance and relationships between resources, manage versions, and describe spatial/temporal resolution or website. Likewise, the responsibility of the license is redefined, moving its declaration to the most appropriate level.
• For distributions: Expanded options to indicate planned availability, legislation, usage policy, integrity, packaged formats, direct download URL, own license, and lifecycle status. 

A practical and gradual approach

Many catalogs already meet the requirements set out in the 2013 version of NTI-RISP. In these cases, the migration to DCAT-AP-ES requires a reduced adjustment, although the guide also contemplates more complex scenarios, following a progressive and adaptable approach. 

The document distinguishes between the minimum compliance required and some extensions that improve quality and interoperability.

It is recommended to follow an iterative strategy: starting from the minimum core to ensure operational continuity and, subsequently, planning the phased incorporation of additional elements, such as data services, contact, applicable legislation, categorization of HVDs and contextual metadata. This approach reduces risks, distributes the effort of adaptation, and favors an orderly transition. 

Once the first adjustments have been made, the catalogue can be federated with both the National Catalogue, hosted in datos.gob.es, and the Official European Data Catalogue, progressively increasing the quality and interoperability of the metadata. 

The guide is a technical support material that facilitates a basic transition, in accordance with the minimum interoperability requirements. In addition, it complements other reference resources, such as the DCAT-AP-ES Application Profile Model and Implementation Technical Guide, the implementation examples (Migration from NIT-RISP to DCAT-AP-ES and Migration from NTI-RISP to DCAT-AP-ES HHD), and the  complementary conventions to the DCAT-AP-ES model that define additional rules to address practical needs.