Publishing your catalogue on Joinup
Joinup makes use of the ADMS specification to enable semantic interoperability between catalogues; ADMS describes all the details of the data exchanged between external catalogues and Joinup. In short it describes the form of the data: what makes up a solution, a distribution etc.
ADMS forms the contract between the external catalogues and Joinup.
By using Linked Data to exchange the data, all information is uniquely identifiable, independent of the source. This is important, as it makes sure that the information from multiple sources can be merged without conflicts, and makes updating easier.
In contrast, it is quite common for other technologies to use numeric, incremental identifiers, which have no universal meaning.
The federation process
The first step for making solutions available on Joinup through federation is by describing them using ADMS-AP (v2).
Depending on the source system, a transformation of some sort into RDF will have to take place, resulting in an RDF file.
To validate this file for conformance, the ADMS-AP validator that is available on Joinup can be used. If you want to test for conformance as part of an automated process, the validator made available by SEMIC can be used. Once the file is conformant, the next step is to publish it on a public accessible location. The Joinup federation project can, thus, regularly fetch this file and keep its copy of the solutions up-to-date.
Tips for a smooth federation
- Persistent identifiers:
An important aspect of data governance is ensuring the longevity of the data, of which assigning persistent identifiers is an important aspect. Since solutions described by ADMS-AP need a URI as an identifier (RDF), it is recommended to look into the report on ‘10 Rules for Persistent URIs’, as it contains good guidelines which ideally lead to the development of a persistent URI policy.
- Licences:
The ADMS-AP specification contains a class to describe licences. Joinup contains a list of licences compliant with ADMS. To avoid that the same licence is present multiple times in Joinup, we try to avoid federating licences. Since a reference dataset for licences exist outside of the ADMS model, we decided to link all Joinup licences to their SPDX equivalent. This way, either Joinup or SPDX licence identifiers can be used when linking to Licences from Distributions.
- EIRA:
The ADMS-AP specification defines that the ‘Dataset type’ points to an old release of the EIRA specification. It is recommended to use the latest version instead, as this will make solutions much more discoverable.
Where to go from here
If you would like to see your solutions on Joinup through federation, then please contact our team. We will provide all the necessary details and next steps in order to make this process as effortless as possible from your side.