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Re: how to get JSON from SPARQL endpoint without content negotiation: output=json standard??

From: Sergio Fernández <sergio.fernandez@fundacionctic.org>
Date: Sat, 10 Mar 2012 20:50:34 +0100
Message-ID: <CAMR8oe2_C_5juycOhmy4vLxBosFBTshLzSoyb=F_fk2LZvCRQg@mail.gmail.com>
To: Gregg Kellogg <greggkellogg@gmail.com>
Cc: Iker Huerga <iker.huerga@gmail.com>, Jeremy Carroll <jeremy@topquadrant.com>, "semantic-web@w3.org" <semantic-web@w3.org>
There is no a standard query string for such purpose on the current
working documents:
http://www.w3.org/TR/sparql11-protocol/#query-operation

Not sure why the feature request pointed by Iker is not covered by the
new drafts.

But since it's useful on some situations, some implementations added a
parameter for force the format; and as far as I know, usually 'format'
is used for that.

On 10 March 2012 05:59, Gregg Kellogg <greggkellogg@gmail.com> wrote:
> My implementation looks at the accept header to determine the format to
> return.
>
> Gregg Kellogg
> Sent from my iPhone
>
> On Mar 9, 2012, at 9:49 PM, Iker Huerga <iker.huerga@gmail.com> wrote:
>
> Hi,
>
> At least from my understanding this is endpoint dependent and is
> not standardized. I think there was some discussion about this a couple of
> years ago, you can take a look at [1].
>
> Hope this helps
>
> [1]  http://www.w3.org/2009/sparql/wiki/Feature:ReturnFormatKeyword
>
> 2012/3/9 Jeremy Carroll <jeremy@topquadrant.com>
>>
>> I am chasing through the standards trying to understand how to poke a
>> SPARQL endpoint to give me JSON in a conformant fashion.
>>
>> So far I have that I can set my accept headers to ask for
>> application/sparql-results+json
>>
>> I also note that different endpoints also seem to support additional query
>> parameters to make this work e.g.
>>
>> http://dbpedia.org/sparql?query=select%20?book%20where%20{}&output=json
>> http://dbpedia.org/sparql?query=select%20?book%20where%20{}&format=json
>>
>>
>> http://data.linkedmdb.org/sparql?query=select%20?book%20where%20{}&output=json
>>
>> http://lobid.org/sparql/?query=select ?b where {}&output=json
>>
>> I don't see where this output=json thing is documented ....
>>
>> thanks
>>
>> Jeremy
>>
>>
>>
>
>
>
> --
> Iker Huerga
> http://www.ikerhuerga.com/
>



-- 
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Received on Saturday, 10 March 2012 19:51:22 UTC

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