Setting custom headers in YASGUI tabs

The simple test frontend of the Qanary reference implementation offers a YASGUI Web interface (c.f., YASGUI project) for writing and executing SPARQL queries.

Problem

Typically all triplestores require specific HTTP headers to be accessed properly.

Stardog triplestore

• If Stardog is used as Qanary triplestore, then in order to query the Qanary triplestore endpoint you need to define two specific request headers.
• Observations: Executing a query on the triplestore endpoint without these headers returns Unauthorized(#401).
  • By default this applies to the tabs find computed query and find all created annotations in the simple Qanary frontend (locally available at http://localhost:8080/startquestionansweringwithtextquestion).

Solution

• Because they are not set automatically you will have to add them by yourself with the following steps:
  • Click on settings (gear icon) next to the endpoint.
  • Under Header Arguments set:
    • Accept in the first input field and application/sparql-results+json in the second.
    • Use the two new blank input fields to set Authorization to Basic YWRtaW46YWRtaW4= the same way.
• You will have to set these headers for every tab that is used to query the Stardog triplestore.
• Changing a tab's endpoint might require you to set different headers as well.

Other triplestores

Please let us know if you can provides specific configurations for other triplestores.