Thank's for your reply.
All the failing queries was on the following model
SELECT distinct ?candidate ?label WHERE {
SERVICE wikibase:mwapi {
bd:serviceParam wikibase:api "EntitySearch" .
bd:serviceParam wikibase:endpoint "www.wikidata.org" .
bd:serviceParam mwapi:search "Musée Cernuschi" .
bd:serviceParam mwapi:language "fr" .
bd:serviceParam wikibase:limit 5 .
?candidate wikibase:apiOutputItem mwapi:item .
}
?candidate wdt:P17 wd:Q142 .
SERVICE wikibase:mwapi {
bd:serviceParam wikibase:api "EntitySearch" .
bd:serviceParam wikibase:endpoint "www.wikidata.org" .
bd:serviceParam mwapi:search "Paris" .
bd:serviceParam mwapi:language "fr" .
bd:serviceParam wikibase:limit 5 .
?city wikibase:apiOutputItem mwapi:item .
}
?candidate wdt:P131 ?city .
?candidate rdfs:label ?label;
filter(lang(?label)="fr")
}
I don't think that are queries producing big load.
I had a lot of response sometimes empty, sometimes correct on such
query testing the same query several times.
But, I can't reproduce such results this week. And, so, it is
difficult to analyze the problem without reproducing it.
--
Jean-Claude Moissinac
Le mer. 9 janv. 2019 à 00:29, Stas Malyshev <smalyshev(a)wikimedia.org> a
écrit :
Hi!
Is there a good mean to query the sparql wdqs
service of wikidata?
I've tried some python code to do it, with relative success.
Success, because some requests gives the expected result.
Relative, because the same query sometimes gives an empty response
either from my code or directly in the WDQS interface, where it's
possible to see that a sparql query sometimes gives an empty response,
sometimes the expected reponse without message or status to know that
the response is erroneous.
(demo is difficult, because it seems to depend of the load of the wdqs
service)
Looks like you're running some heavy queries. So the question would be,
which queries are those and how often do you run them?
I've found the following info:
*
https://www.mediawiki.org/wiki/Wikidata_Query_Service/User_Manual#Query_lim…
,
which suggest a possible error HTTP code |429,
which I never receive|
429 means you're calling the service too fast or too frequently. If you
are just running a single query, you never get 429.
*
https://phabricator.wikimedia.org/T179879,
which suggest a possible
connexion with OAuth, but such possibility is never documented in the
official documentation
is an open task, thus it's not
implemented yet.
None of them gives a practical method to get a
response and trust it.
Any method that uses HTTP access to SPARQL endpoint would give you the
same result. Which depends on query. So I'd suggest providing some info
about the queries and specific issues you're having, and then we could
see if it's possible to improve it.
--
Stas Malyshev
smalyshev(a)wikimedia.org