Ask Your Question
0

Service call failed in json-prolog while querying an owl file in Cram

asked 2017-09-13 09:47:17 -0500

aAsoodeh gravatar image

updated 2017-09-13 12:49:31 -0500

jayess gravatar image

Hi,

I started a roslisp node in cram and have json-prolog query services (i can see

/json_prolog/finish
/json_prolog/next_solution
/json_prolog/query
/json_prolog/simple_query

when i do "rosservice list").

Also by typing (json-prolog:check-connection) i receive T. so i assume that everything set up properly.

problem is when i try any query like

(json-prolog:prolog '("rdf_has" ?owlname "http://knowrob.org/kb/srdl2-comp.owl#urdfName" ("literal" ?var)))

i receive

Prolog query failed: Got error: The value
             |'["rdf_has",{"variable":"OWLNAME"},"http://knowrob.org/kb/srdl2-comp.owl#urdfName",{"term":["literal",{"variable":"VAR"}]}]'|
           is not of type
             LIST..

also i have

[(JSON-PROLOG) WARN] 1505226166.532: Service call failed. 
[(JSON-PROLOG) WARN] 1505226166.532: Retrying...

Thanks

edit retag flag offensive close merge delete

1 Answer

Sort by ยป oldest newest most voted
0

answered 2017-09-13 10:20:37 -0500

gaya gravatar image

Hi,

This seems like an error on the KnowRob side. I execute it on my machine and it works fine. I'm using the master branch of KnowRob (on 14.04), the latest commit I have is from 3rd of September. And I'm using the latest version of cram_json_prolog, master branch, last commit was on 26 June. Try prolog-simple or a simpler query in general.

edit flag offensive delete link more

Comments

same error when trying prolog-simple. do you know any cram project that i can use as pattern to build a clear project? any tutorial? Thanks

aAsoodeh gravatar imageaAsoodeh ( 2017-09-13 12:37:12 -0500 )edit

We have a bunch of tutorials. Here is he one that showcases most complex behaviors It runs on the newest CRAM version (0.4.0). Consult the installation page to get the latest version.

gaya gravatar imagegaya ( 2017-09-18 14:09:49 -0500 )edit

Your Answer

Please start posting anonymously - your entry will be published after you log in or create a new account.

Add Answer

Question Tools

1 follower

Stats

Asked: 2017-09-13 09:47:17 -0500

Seen: 88 times

Last updated: Sep 13 '17