Linked Data Fragments endpoint returns IllegalStateException - Wikidata

Guillaume Lederrey

18 Dec 18 Dec

9:01 a.m.

Hello! This looks like a bug, but we'll need more time to investigate and get to the bottom of this. I've created https://phabricator.wikimedia.org/T2704 to track the issue. There isn't that many people around during this end of year, so this will probably have to wait for January. Thanks for your patience! Guillaume On Thu, Dec 17, 2020 at 4:06 PM Maciej Gawinecki <mgawinecki(a)gmail.com> wrote:

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Hi, I am trying to get alternative names of given names in WikiData with the following simple query: PREFIX ps: <http://www.wikidata.org/prop/direct/> PREFIX wd: <http://www.wikidata.org/entity/> PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#> CONSTRUCT {?s rdfs:label ?o} WHERE { ?s ps:P31 wd:Q202444. ?s rdfs:label ?o} LIMIT 1000 Initially, the query was much more complex, but I was getting time-outs on the public WikiData SPARQL endpoint. I decided to use Linked Data Fragments to offload some filtering from the server to the client. comunica-sparql "https://query.wikidata.org/bigdata/ldf" -f query > given_names.n3 (where "query" is a file with the SPARQL query shown above). Unfortunately, the client tries to get output from the 3rd page, I am getting the following error: Could not retrieve https://query.wikidata.org/bigdata/ldf?subject=http%3A%2F%2Fwww.wikidata.or… (500: unknown error) Following the link in fact returns HTTP 500 error with Error details java.lang.IllegalStateException The link points to the 3rd page. It works if you try to go the second page: https://query.wikidata.org/bigdata/ldf?subject=http%3A%2F%2Fwww.wikidata.or… Is this a bug or a limitation of a service? With kind regards, Maciej Gawinecki _______________________________________________ Wikidata mailing list Wikidata(a)lists.wikimedia.org https://lists.wikimedia.org/mailman/listinfo/wikidata

-- *Guillaume Lederrey* (he/him) Engineering Manager Wikimedia Foundation <https://wikimediafoundation.org/>

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Ryan Kemper

8:02 p.m.

Hi Maciej, Thanks for noticing the error in the ticket provided. I did a search on "*Linked Data Fragments endpoint returns IllegalStateException*" and found the correct ticket: *https://phabricator.wikimedia.org/T270476 <https://phabricator.wikimedia.org/T270476>* (looks like the last two digits got chomped in Guillaume's message) I don't see the ticket assigned/triaged at the moment so I'll try to make sure it gets looked at in our next planning cycle. Sorry for the delay. Ryan On Tue, Jan 12, 2021 at 8:29 AM Maciej Gawinecki <mgawinecki(a)gmail.com> wrote:

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Hi Guillaume, Thanks for reporting the issue in the bug tracker. Is the link you have provided, https://phabricator.wikimedia.org/T2704, correct? The last activity in that ticket was in 2014... Thanks, Maciej Gawinecki czw., 17 gru 2020 o 16:05 Maciej Gawinecki <mgawinecki(a)gmail.com> napisał(a):

Hi, I am trying to get alternative names of given names in WikiData with the following simple query: PREFIX ps: <http://www.wikidata.org/prop/direct/> PREFIX wd: <http://www.wikidata.org/entity/> PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#> CONSTRUCT {?s rdfs:label ?o} WHERE { ?s ps:P31 wd:Q202444. ?s rdfs:label ?o} LIMIT 1000 Initially, the query was much more complex, but I was getting time-outs on the public WikiData SPARQL endpoint. I decided to use Linked Data Fragments to offload some filtering from the server to the client. comunica-sparql "https://query.wikidata.org/bigdata/ldf" -f query > given_names.n3 (where "query" is a file with the SPARQL query shown above). Unfortunately, the client tries to get output from the 3rd page, I am getting the following error: Could not retrieve https://query.wikidata.org/bigdata/ldf?subject=http%3A%2F%2Fwww.wikidata.or… (500: unknown error) Following the link in fact returns HTTP 500 error with Error details java.lang.IllegalStateException The link points to the 3rd page. It works if you try to go the second page: https://query.wikidata.org/bigdata/ldf?subject=http%3A%2F%2Fwww.wikidata.or… Is this a bug or a limitation of a service? With kind regards, Maciej Gawinecki

_______________________________________________ Wikidata mailing list Wikidata(a)lists.wikimedia.org https://lists.wikimedia.org/mailman/listinfo/wikidata

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Maciej Gawinecki

29 Mar 29 Mar

2:38 p.m.

Hi there, I reported the problem in December 2020. I can see this has not been even assigned to any one: https://phabricator.wikimedia.org/T270476 Do you need any help to fix it? Thank you, Maciej Gawinecki śr., 13 sty 2021 o 09:37 Guillaume Lederrey <glederrey(a)wikimedia.org> napisał(a):

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On Tue, Jan 12, 2021 at 9:03 PM Ryan Kemper <rkemper(a)wikimedia.org> wrote:

Hi Maciej, Thanks for noticing the error in the ticket provided. I did a search on "*Linked Data Fragments endpoint returns IllegalStateException*" and found the correct ticket: *https://phabricator.wikimedia.org/T270476 <https://phabricator.wikimedia.org/T270476>* (looks like the last two digits got chomped in Guillaume's message) I don't see the ticket assigned/triaged at the moment so I'll try to make sure it gets looked at in our next planning cycle. Sorry for the delay.

For some precision on the timeline: this means we'll push this ticket on our queue of current work next Monday. It might take a few weeks before we have time to actually work on it. But this is definitely not lost!

Ryan On Tue, Jan 12, 2021 at 8:29 AM Maciej Gawinecki <mgawinecki(a)gmail.com> wrote:

Hi Guillaume, Thanks for reporting the issue in the bug tracker. Is the link you have provided, https://phabricator.wikimedia.org/T2704, correct? The last activity in that ticket was in 2014... Thanks, Maciej Gawinecki czw., 17 gru 2020 o 16:05 Maciej Gawinecki <mgawinecki(a)gmail.com> napisał(a):

Hi, I am trying to get alternative names of given names in WikiData with the following simple query: PREFIX ps: <http://www.wikidata.org/prop/direct/> PREFIX wd: <http://www.wikidata.org/entity/> PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#> CONSTRUCT {?s rdfs:label ?o} WHERE { ?s ps:P31 wd:Q202444. ?s rdfs:label ?o} LIMIT 1000 Initially, the query was much more complex, but I was getting time-outs on the public WikiData SPARQL endpoint. I decided to use Linked Data Fragments to offload some filtering from the server to the client. comunica-sparql "https://query.wikidata.org/bigdata/ldf" -f query > given_names.n3 (where "query" is a file with the SPARQL query shown above). Unfortunately, the client tries to get output from the 3rd page, I am getting the following error: Could not retrieve https://query.wikidata.org/bigdata/ldf?subject=http%3A%2F%2Fwww.wikidata.or… (500: unknown error) Following the link in fact returns HTTP 500 error with Error details java.lang.IllegalStateException The link points to the 3rd page. It works if you try to go the second page: https://query.wikidata.org/bigdata/ldf?subject=http%3A%2F%2Fwww.wikidata.or… Is this a bug or a limitation of a service? With kind regards, Maciej Gawinecki

_______________________________________________ Wikidata mailing list Wikidata(a)lists.wikimedia.org https://lists.wikimedia.org/mailman/listinfo/wikidata

-- *Guillaume Lederrey* (he/him) Engineering Manager Wikimedia Foundation <https://wikimediafoundation.org/> _______________________________________________ Wikidata mailing list Wikidata(a)lists.wikimedia.org https://lists.wikimedia.org/mailman/listinfo/wikidata

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