On 10/09/15 19:06, Mark Feblowitz wrote:
I didn’t quite care that it was JSON-LD - only that I could get json to be
emitted. the application/rdf+json worked for this.
I’m using fuseki 1.0.1 at the moment.
There wasn't JSON-LD in Fuseki 1.0.0
When you say it worked for you, was that with CONSTRUCT or SELECT?
CONSTRUCT and DESCRIBE
SELECT does not return graphs.
application/sparql-results+json returns JSON rsult sets.
Now I have a wish: As I’m viewing the results as output using
application/rdf+json, I am noticing that it’s very basic triples. What the
consumer of this result really wants is a hybrid of triples and resultsets. So,
it produces triples as specified in the CONSTRUCT and it also incorporates
variable names into the JSON, as present in resultsets.
Talis's RDF/json format is intentionally simple.
That is, the emitted json is presented as URIs for the Subject, Predicate, and
Object (with additional syntax to handle sub-parts and arrays of Objects).
Tthe hybrid would somehow also incorporate variable names, so instead of URI-S
URI-P URI-O it would be something like
{ S : {id : URI-S, [ { P: {id: URI-P, [ O: {id: URI-O} ] ] }} ] } }
where S, P, and O would be ?S, ?P, and ?O.
Doable? Something JSON-LD might be able to handle?
application/sparql-results+json ?
Otherwise you'll need to add an output format. Though easier maybe
3-tier: use Fuseki as the database layer and have custom formatter as a
webservice running as a logic layer.
Or maybe Elda
http://www.epimorphics.com/web/tools/elda.html
Thanks
On Sep 10, 2015, at 1:39 PM, Andy Seaborne <[email protected]> wrote:
On 10/09/15 18:20, Mark Feblowitz wrote:
Ok -
I tested all forms that you recommended, and the one that does work is
application/rdf+json.
Caveat - that's not JSON-LD.
https://jena.apache.org/documentation/io/rdf-json.html
Thanks very much for the suggestion!
Mark
On Sep 10, 2015, at 12:16 PM, Mark Feblowitz <[email protected]> wrote:
That makes sense. But it doesn’t seem to work. I still get it in RDF XML format.
I’m wondering whether the problem is with how I’m submitting the query.
I’m using curl as follows:
curl -v -H "Content-Type:application/sparql-query" -H “Accept: application/ld+json"
-X POST http://host:port/ds/sparql <http://host:port/ds/sparql> -d …
Works for me (Fuseki1 and Fuseki2, latest).
Which version of Fuseki? (did it have JSON-LD?)
Andy
Should I instead be using a URL parameter?
Thanks,
Mark
On Sep 9, 2015, at 1:33 PM, Colin Maudry <[email protected]
<mailto:[email protected]>> wrote:
Hi Mark,
This is because CONSTRUCT doesn't return query results (a table
structure), but a graph.
Two possibilities :
* If you want to stick to your CONSTRUCT query and want JSON out, you
should request JSON-LD[1] with "application/ld+json". You can also
try "application/json" or "application/rdf+json" to get RDF/JSON (I
never tried). According to the spec[2], you're encouraged to use
JSON-LD instead.
* If you really want JSON SPARQL results, that's a SELECT query that
you need to post.
I hope it helps.
Colin Maudry
[1] http://www.w3.org/TR/json-ld/ <http://www.w3.org/TR/json-ld/>
[2] http://www.w3.org/TR/rdf-json/ <http://www.w3.org/TR/rdf-json/>
On 09/09/2015 18:58, Mark Feblowitz wrote:
At my wits’ end here - when I invoke a SPARQL using curl to a local Fuseki
server, and the query is a construct query, and I specify
-H “Accept: application/sparql-results+json”
or
-H “Accept: application/sparql-results%2Bjson”
I consistently get results back in RDF/XML
<rdfs99:RDF
xmlns:dp="http://dbpedia.org/property/ <http://dbpedia.org/property/>"
xmlns:yago="http://dbpedia.org/class/yago/ <http://dbpedia.org/class/yago/>"
xmlns:nsl="http://purl.org/ontology/storyline/“
<http://purl.org/ontology/storyline/%E2%80%9C>
...
With no "-H Accept…”, I’m seeing triples format.
In fact, no matter what I set the Accept header to, I see rdf/xml. Without an
Accept: header, I see ntriples.
Any ideas?
