Feature:Query response linking

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Feature: Query response linking

Support contextual links from all query responses

Feature description

The SPARQL XML Results format currently supports a link element allowing references to additional metadata to be included in the response. However this feature is limited as there is no way for a client to select between the possible alternatives. A "rel" attribute similar to HTML would be one way to enable this, as would allowing additional elements from extra namespaces to be included in the response.

A typical example of using this feature would be to link back to the original endpoint, or to licensing metadata associated with the request.

However currently this feature has no equivalent for CONSTRUCT/DESCRIBE queries. It is potentially legal for an endpoint to include additional statements that refer to the response document, but it is more likely that clients will simply treat these statements as part of the results, rather than separate metadata about the result document.

Example

Allow, e.g.:

<link rel="license" href="..."/>

and/or

<rdf:Description rdf:about="...">
 ...statements about response document...
</rdf:Description>

... query results ...


Existing Implementation(s)

None known.

Existing Specification / Documentation

None known.

Compatibility

Potential effect on existing query response parsers? Unlikely?

Links to postponed Issues

None known.

Champions

Use cases

  • Make the protocol more RESTful by allowing hypertext linking, from all result formats
  • Allow linking to, or embedding of license statements relating to the data in the results
  • Allow linking to a service description for the endpoint and/or VoiD description of the dataset [1]
  • Link back to the web service endpoint that produced the result, in order to re-run the query later.
  • Link to the web application that can be used to edit the query and let the user run the modified version.

References

Originally suggested by Leigh Dodds in a message of 2009-Mar-06.