SPARQL endpoint as a service
If [accept] header is RDF (or turtle or whatever), the query is just directed (proxied) to the [triple-store], SPARQL endpoint and executed.
Test
Using an HTTP client GUI, for example POSTMAN or CURL:
If using GET http method
Url: https://id.euskadi.eus/sparql?query=DESCRIBE <https://opendata.euskadi.eus/catalogo/-/aquariums-de-euskadi/>
Method: GET
Accept header: Accept=rdf
CURL: curl -X GET 'https://id.euskadi.eus/sparql?query=DESCRIBE <https://opendata.euskadi.eus/catalogo/-/aquariums-de-euskadi/>' \
-H 'accept: application/rdf+xml'
Result: an RDF representation of the query result.
If using POST http method
Url: https://id.euskadi.eus/sparql?query=DESCRIBE <https://opendata.euskadi.eus/catalogo/-/aquariums-de-euskadi/>
Method: POST
Accept header: Accept=rdf
Body: form url encoded
query=DESCRIBE <https://opendata.euskadi.eus/catalogo/-/aquariums-de-euskadi/>
CURL: curl -X POST https://id.euskadi.eus/sparql \
-H 'accept: application/rdf+xml' \
-H 'content-type: application/x-www-form-urlencoded' \
-d query=DESCRIBE <https://opendata.euskadi.eus/catalogo/-/aquariums-de-euskadi/>
Result: an RDF representation of the query result.