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Terminology source availability status

· 2 min read
David de Boer
Software Architect & Developer

The Network of Terms now monitors each terminology source and exposes its availability via the website and the GraphQL API.

Why availability matters​

The Network of Terms queries terminology sources in real time. If a source’s SPARQL endpoint is down, searches against that source will fail. Until now, there was no way to know upfront whether a source was available – you'd only find out after a failed query.

With the new status field on each source, you can check availability before querying. This lets you inform users proactively, for example by showing a warning badge next to unavailable sources. When searching multiple sources in a single query, you can decide to temporarily skip sources that are unavailable so users won’t have to wait for them.

How it works​

The Network of Terms periodically checks each source's SPARQL endpoint. The result is exposed through a status field on the Source type in the GraphQL API:

query Sources {
  sources {
    uri
    name
    status {
      isAvailable
      lastChecked
    }
  }
}

The status object contains two fields:

  • isAvailable: whether the source's endpoint responded successfully at the last check
  • lastChecked: when the last availability check was performed (ISO 8601 timestamp).

On the website​

On the Network of Terms website, availability is shown in two places: in the search form where you select sources, and on the list of terminology sources.

For developers, the status field is available in any GraphQL query that returns source information – both when listing sources and when searching terms. This makes it easy to combine search results with up-to-date availability information.

Relation to the NDE status page​

This feature complements the NDE status page we launched recently. While the status page monitors the Network of Terms service itself, the status field monitors the individual terminology sources that the Network of Terms queries. Together, they give you a complete picture of availability.